Solar powered plane

Abstract

A solar powered plane configured to operate in the stratosphere includes a hinged vertical stabiliser that that pivots about a hinge; the stabiliser extends both above the fuselage and also below the fuselage, and the base of the vertical stabiliser includes a skid. The hinged vertical stabiliser is configured such that when the skid contacts the ground on landing, the top of the vertical stabiliser pivots forwards around the hinge point, minimising damage to the aircraft on landing. the skid includes a lightweight, replaceable sacrificial layer.

Description

[0001] 1 Attorney Docket No.391529.00003 SOLAR POWERED PLANE Field of the invention This invention relates to a solar powered plane; the plane is a UAV (unmanned aerial vehicle) configured to take-off and land at a conventional runway and to ascend to the stratosphere and to then operate in the stratosphere for days, weeks or even months. Implementations can operate as high altitude platform stations (known as HAPS), which are long endurance, high altitude planes able to offer various services, such as observation and communications. Other terms used to describe this class of aircraft include solar gliders and high altitude solar powered platforms. The solar powered plane described in this specification has many applications, such as weather monitoring, earth observation and earth imaging, border security, maritime patrols, anti-piracy operations, disaster response and agricultural observation. Description of the Prior Art Designing a stratospheric solar powered plane presents multiple challenges: the plane has to be light and yet rigid enough to survive the ascent and descent from stratospheric altitudes. It has to be light and yet able to lift a significant payload. It has to be light and yet be equipped with sufficient batteries and PV cells to enable it to stay in the air for many days, weeks or even months. It should ideally be low cost, straightforward to manufacture and service, be re-usable, have a configurable payload layout, and have the flight stability essential for high precision data-gathering. There have been numerous attempts to design stratospheric solar powered plane, including the NASA Pathfinder (1993), Pathfinder Plus (1998), NASA Centurion / Helios (1999), Airbus Zephyr (2005 to date), Titan Aerospace Solara (2012 - 2017), Korea Aerospace Research Institute EAV 92010 - 2015), Astigan A3 (2014 - 2021), and Facebook Aquila (2016 - 2018). These planes are however complex and costly to build and repair; some have very limited re- useability. 2 Attorney Docket No.391529.00003 Reference may be made to WO 2018 / 234798, WO 2018 / 234799, WO 2014 / 013268, US 9,169,014, WO 2017 / 207968, WO 2018 / 237797, WO 2018 / 234797, WO 2017 / 051159, WO 2017 / 051160, the contents of which are incorporated by reference. US Patent No.10,214,295 for High-efficiency, lightweight solar sheets by inventors Pan et al., filed May 8, 2017 and issued February 26, 2019, discloses embodiments including a high efficiency, lightweight solar sheet. Some embodiments include a solar sheet configured for installation on a surface of a UAV or on a surface of a component of a UAV. The solar sheet includes a plurality of solar cells and a polymer layer to which the plurality of solar cells are attached. Some embodiments include a kit for supplying solar power in a battery-powered or fuel cell powered unmanned aerial vehicle (UAV) by incorporating flexible solar cells into a component of a UAV, affixing flexible solar cells to a surface of a UAV, or affixing flexible solar cells to a surface of a component of a UAV. The kit also includes a power conditioning system configured to operate the solar cells within a desired power range and configured to provide power having a voltage compatible with an electrical system of the UAV. US Patent No. 9,957,037 for High altitude aircraft with integrated solar cells, and associated systems and methods by inventors Cornew et al., filed June 20, 2014 and issued May 1, 2018, discloses a method of making a solar cell assembly including placing backsides of multiple solar cells in contact with a substrate. The solar cells are electrically connected to each other. Heat and pressure are applied to the solar cells and the substrate to simultaneously impress the solar cells into the substrate and bond the solar cells to the substrate. US Patent No.8,322,650 for Aircraft by inventors Kelleher et al., filed July 30, 2010 and issued December 4, 2012, discloses an aircraft, particularly a solar powered, high altitude, long endurance, unmanned aerial vehicle, being equipped with a combination of canted down, raked back wing tips and trailing “tip tails” carried on booms from the tip regions of the mainplane. Each tip tail is positioned to be subject to the upwash field of the respective wing tip vortex, at least in the cruise condition of the aircraft. The wing tip form can achieve a reduction in induced drag and help to relieve wing root bending moment while the tip tails can act through their connections to the mainplane to provide torsional relief to the latter, particularly under lower incidence / higher speed conditions. In the higher incidence / lower speed cruise condition, however, the presence of the tip tails in the upwash fields of the wing tip vortices means that 3 Attorney Docket No.391529.00003 they can generate lift with a component in the forward direction of flight and hence contribute to the thrust requirements of the aircraft. US Patent No. 9,169,014 for Unmanned aerial vehicle and method of launching by inventors Elson et al., filed August 8, 2012 and issued October 27, 2015, discloses a method of launching a powered unmanned aerial vehicle at an altitude of at least 13,000 m, the method comprising lifting the vehicle by attachment to a lighter-than-air carrier from a substantially ground-level location to an elevated altitude, causing the vehicle to detach from the carrier while the velocity of the vehicle relative to the carrier is substantially zero, the vehicle thereafter decreasing in altitude as it accelerates to a velocity where it is capable of preventing any further descent and can begin independent sustained flight. US Patent No.7,789,339 for Modular articulated-wing aircraft by inventor Sommer, filed June 27, 2006 and issued September 7, 2010, discloses systems and / or methods for forming a multiple-articulated flying system (skybase) having a high aspect ratio wing platform, operable to loiter over an area of interest at a high altitude are provided. In certain exemplary embodiments, autonomous modular flyers join together in a wingtip-to-wingtip manner. Such modular flyers may derive their power from insolation. The autonomous flyers may include sensors which operate individually, or collectively after a skybase is formed. The skybase preferably may be aggregated, disaggregated, and / or re-aggregated as called for by the prevailing conditions. Thus, it may be possible to provide a “forever-on-station” aircraft. US Patent Publication No. 2022 / 0411047 for Aerial vehicles with transitioning landing gear and related methods by inventor Mihai, filed May 19, 2022 and published December 29, 2022, discloses aerial vehicles selectively transitioning between a fixed wing flight configuration and a vertical takeoff and landing (VTOL) configuration. In the fixed wing flight configuration, a forward propeller may rotate in a first forward plane, whereas in the VTOL configuration, the forward propeller may be tilted to rotate in a second forward plane. A forward landing arm may extend downward in the VTOL configuration and be configured to be tilted to a stowed position when the aerial vehicle is in the fixed wing flight configuration. The forward landing arm may be coupled to the forward propeller such that tilting of the forward propeller causes corresponding tilting of the forward landing arm. In some examples, a plurality of such landing 4 Attorney Docket No.391529.00003 arms and propellers are tilted during transitioning of the aerial vehicle, such as one or more forward propellers and landing arms and / or one or more aft propellers and landing arms. US Patent No.10,836,480 for Flight vehicle by inventors Heinen et al., filed October 26, 2017 and issued November 17, 2020, discloses a method and apparatus for a flight vehicle including a wing having a high aspect ratio and first and second rotors having a high aspect ratio, with a ratio of the rotor diameter to wing length ratio is equal to or greater than about 0.25. In embodiments, the flight vehicle can include a first and second motor, each less than about one thousand HP, to drive a respective rotor and a second motor. The flight vehicle can include a cruise mode and a VTOL mode. US Patent No. 7,922,115 for Modular unmanned air-vehicle by inventors Colgren et al., filed April 23, 2007 and issued April 12, 2011, discloses an unmanned air vehicle designed for reconnaissance, surveillance, data acquisition, and general research. The air vehicle is a monoplane that consists of several pieces that can easily be assembled using a minimal amount of tools. The air vehicle consists of a forward and aft fuselage section, two identical horizontal stabilizers, and four identical wing sections. The aircraft can fly with all four wing sections, or with just two wing sections (the short wing configuration). Each of the four wing sections of the air vehicle can be interchanged with any of the other wing sections for the purpose of minimizing assembly time and spare parts. US Patent No. 8,146,855 for Unmanned air vehicle by inventor Ismailov, filed September 3, 2008 and issued April 3, 2012, discloses an unmanned air vehicle for military, land security and the like operations including a fuselage provided with foldable wings having leading edge flaps and trailing edge ailerons which are operable during ascent from launch to control the flight pattern with the wings folded, the wings being deployed into an open unfolded position when appropriate. The vehicle is contained within a pod from which it is launched and a landing deck is provided to decelerate and arrest the vehicle upon its return to land. US Patent Publication No. 2021 / 0309353 for Modular unmanned aerial vehicle system for adaptable parcel delivery by inventor Gil, filed March 30, 2021 and published October 7, 2021, discloses a modular unmanned aerial vehicle (UAV) system comprising a body module, a rotor module, and a wing module. The body module includes a flight controller and a power 5 Attorney Docket No.391529.00003 distribution device. The body module is releasably attachable to the rotor module or the wing module, and the body module is releasably attachable to the rotor module. The rotor module includes one or more motors and electronic speed controllers (ESCs), while the wing module includes a wing having a flap, elevator, aileron, or rudder. Various UAV configurations can be formed from the body module, the rotor module, and the wing module. Each configuration includes different advantages for flight time, distance, battery life, and payload capacity. A UAV can be configured to a particular configuration to optimize parcel delivery. US Patent Publication No. 2023 / 0145112 for Aircraft by inventors Bishop et al., filed March 29, 2021 and published May 11, 2023, discloses an aircraft comprising: a fuselage; and a payload module coupled to the fuselage, the payload module comprising one or more data storage devices. The payload module is configured to be decoupled from the fuselage during flight upon receipt of a de-coupling input. US Patent No.11,414,191 for Remotely controlled modular VTOL aircraft and re-configurable system using same by inventors Gibboney et al., filed July 27, 2019 and issued August 16, 2022, discloses a manned / unmanned aerial vehicle adapted for vertical takeoff and landing using the same set of engines for takeoff and landing as well as for forward flight. An aerial vehicle which is adapted to takeoff with the wings in a vertical as opposed to horizontal flight attitude which takes off in this vertical attitude and then transitions to a horizontal flight path. A tailless airplane which uses a control system that takes inputs for a traditional tailed airplane and translates those inputs to provide control utilizing non-traditional control methods. US Patent No. 11,312,492 for Rotorcraft-assisted systems and methods for launching and retrieving a fixed-wing aircraft into and from free flight by inventors von Flotow et al., filed October 4, 2018 and issued April 26, 2022, discloses various systems and methods configured to: launch a fixed-wing aircraft from a moving object into free, wing-borne flight using a multicopter; retrieve the multicopter after fixed-wing aircraft launch using a retrieval winch; retrieve the fixed-wing aircraft from free, wing-borne flight back onto the moving object using the multicopter; and retrieve the multicopter after fixed-wing aircraft retrieval using the retrieval winch. 6 Attorney Docket No.391529.00003 US Patent Publication No.2020 / 0108909 for Aircraft longitudinal stability by inventors Elson et al., filed June 20, 2018 and published April 9, 2020, discloses an aircraft having at least one main wing and at least one boom fuselage. The main wing has an aerofoil section having a leading edge, a trailing edge, a chord length extending between the leading edge and the trailing edge, a centre of lift, a flexural centre and a centre of mass. The centre of lift, the flexural centre and the centre of mass are located all within a region at most 4% of the chord length. US Patent Publication No.2020 / 0130810 for Aerial vehicle tether by inventor Elson, filed June 20, 2018 and published April 30, 2020, discloses an aerial vehicle having a wing and a fuselage. A tether is anchored at opposing ends of the wing and / or the fuselage. The tether is arranged to prevent one or more parts of the aerial vehicle from separating from the remainder of the aerial vehicle in the event of structural failure of the aerial vehicle. WIPO Patent Publication No. WO2017207968 for Battery arrangement by inventors Elson et al., filed May 25, 2017 and published December 7, 2017, discloses a battery arrangement and a method of operating a battery arrangement for a solar powered aerial vehicle. The battery arrangement has a plurality of batteries arranged in a plurality of groups, the groups including a first battery group, a second battery group and a third battery group. Each battery group includes one or more batteries, and the method has the following steps: discharging the first battery group via an electrical heating device, the first battery group being at an operative temperature range, the operative temperature range being at or above zero degrees Celsius; warming the second battery group from a non-operative temperature range, the non-operative temperature range being below zero degrees Celsius, to the operative temperature range using heat energy from the electrical heating device. Whilst the first battery group is being discharged and the second battery group is being warmed, the third battery group remains at the non- operative temperature range. US Patent Publication No. 2020 / 0148327 for Method of forming a hollow spar for an aerial vehicle by inventors Elson et al., filed June 20, 2018 and published May 14, 2020, discloses a method of forming a hollow spar for an aerofoil includes forming a sandwich structure having a first structural layer, a second structural layer and a cellular core layer located in between the first structural layer and the second structural layer. At least part of the sandwich structure is removed at intervals corresponding to one or more corner locations, and the sandwich structure 7 Attorney Docket No.391529.00003 is folded at the one or more corner locations to define a hollow space and form the spar. A chordwise extending rib section for an aerofoil has a substantially planar web with a chordwise length; and a reinforcement strip attached to an edge of the web over substantially the majority of the chordwise length. US Patent Publication No. 2018 / 0354603 for Aircraft wing structure by inventor Elson, filed September 19, 2016 and published December 13, 2018, discloses an aircraft having a wing providing the main lifting surface for the aircraft. The wing has a structure supporting an aero- dynamic surface, and the wing has a weight, the wing structure being unable to support its own weight when the aircraft is stationary and under a load of 1 g so as to cause structural failure of the wing. US Patent Publication No.2018 / 0346095 for Foam aerofoil by inventor Elson, filed September 19, 2016 and published December 6, 2018, discloses an aerofoil having at least one space frame and at least one pre-stressed cover supported by the space frame. The space frame has one or more structural members, the structural members including a structural foam material; and the pre-stressed cover forms at least a part of an external aerodynamic surface of the aerofoil. The potential for stratospheric solar powered planes has been recognised for many years, but that potential has yet to be realised in practice. SUMMARY OF THE INVENTION The invention is defined in the appended claims. One implementation is the SolarisTMplane; the features of the Solaris plane are described below. The Solaris plane addresses and solves many of the technical problems (such as manufacturing complexity, manufacturing cost, servicing complexity, repair complexity, re-usability, payload layout configurability, airframe rigidity and the flight stability essential for high precision data-gathering), that have affected earlier stratospheric solar powered planes. 8 Attorney Docket No.391529.00003 FIGURES Aspects of the invention will now be described, by way of example(s), with reference to the following Figures, which each show features of the invention: Figure 1A is a perspective view of the Solaris plane. Figure 1B is an exploded view of the Solaris plane. Figures 2A - M show how spars can be joined together Figures 3A - B shows a spar and its cross-sectional view. Figure 4A is a perspective view of the Solaris plane, indicating a detail at the base of the vertical stabiliser and of the base of the downward facing winglets. Figure 4B is a perspective view of the detail at the base of the vertical stabiliser. Figure 4C is a perspective view of the detail at the base of the downward facing winglets. Figure 5A is a frontal view of the Solaris plane, Figure 5B is a side view of the Solaris plane indicating a detail at the base of the vertical stabiliser and of the base of the downward facing winglets. Figure 5C is a side view of the detail at the base of the downward facing winglets. Figure 5D shows a side view of the detail at the base of the vertical stabiliser. Figure 6A shows a battery pack positioned along the length of a wing in one position. Figure 6B shows the battery pack at a different position. Figure 7 is a plan view of a propeller blade, showing an internal honeycomb core. Figure 8 is a cross sectional view through the Figure 7 propeller blade. Figure 9 is a perspective view of the Figure 7 propeller blade, showing the internal honeycomb core. Figure 10A - C are plan and cross sectional views of a propeller blade with an internal stiffener. Figure 11A - D are plan and cross sectional views of a propeller blade with an internal honeycomb core. Figure 12A - B shows different views of a triangular fuselage formed with a triangular cross- section. Figure 13A-B shows the Solaris plane in operation during flight (Figure 13A) and when landing (Figure 13B). 9 Attorney Docket No.391529.00003 Figure 14A - B shows a detail side view of the vertical tailplane positioned during flight and also when landing. Figure 15 is a top-down view of the Solaris plane, showing small control surfaces (e.g. trim ailerons or controls) that are located behind the main wings. Figure 16A-B are perspective views of the Solaris plane, showing the small control surfaces behind the main wings Figure 17 is a side view of the small control surfaces Figure 18 shows a top view of the surface of the plane made up of a non-heat-shrinkable film substrate and a heat shrinkable border. Figures 19 -21 show an imaging system including a carbon fibre parabolic surface. Figures 22 - 23 shows a ground handling vehicle (AGP) for transporting a Solaris plane. Figure 24 is a schematic of the entire Solaris data processing system. Figure 25 shows a diagram of the Solaris computer system. DETAILED DESCRIPTION The SolarisTMplane In this section, we describe the Solaris plane; the Solaris plane is a twin fuselage or twin boom, solar powered plane optimised for long duration stratospheric flights; it is equipped with electric motors powering propellers optimised for stratospheric operation; the Solaris plane can also glide for extended distances. The electric motors are powered by a combination of power from PV solar cells (e.g. on the upper surface of its wings) and batteries; these batteries are also charged by the PV cells during daylight. The Solaris plane comes in three primary variants: one with a 8m wingspan, one with a 28m wingspan and one with a 32m - 34m wingspan; more generally, Solaris planes have a wingspan of less than approximately 38m. All are dual fuselage, dual propeller designs, with a payload that can be in the central wing section connecting the two fuselages or booms, distributed across the main wings or located in the fuselages; this flexibility enables a broad range of different payloads to be carried, in various configurations optimised for the task required to be performed and the flight mission constraints. Note that for the 32m - 34m variant, the payload capacity of approximately 12Kg marries well to a wide payload inventory of COTS (commercial off-the-shelf) instruments / sensors / cameras 10 Attorney Docket No.391529.00003 and CubeSat payload dimensions; the wingspan is not so large as to require a heavy airframe, with all the negative consequences that entails, yet not so small that the payload is insufficient for commercially viable payloads. It can be thought of as occupying the sweet-spot across various parameters, given the constraints of today's material performance (e.g. airframe strength to weight ratio, battery power to weight ratio, PV output etc) and today's payload size and weight. As material performance improves, the 28m variant may prove to be at the sweet- spot. Equally, much larger payloads may be needed in the future, in which case the 32m - 34m variant may be needed. The variants implement a number of innovative features. In this section, we classify these features into the following 6 general categories: Key Feature Group A. Design of the plane Key Feature Group B. Photo Voltaics Key Feature Group C. Imaging systems Key Feature Group D. Connectivity Key Feature Group E. Launch and recovery Key Feature Group F. Use cases We can summarise these as follows: Key Feature Group A: Design of the plane A.1 Modular construction A.2 Carbon fibre spar A.3 Downward winglet that acts as landing skid A.4 Battery re-positioning for optimal balancing A.5 Batteries and payload positioned in the dihedral wings A.6 Over-sized foam core used in the carbon fibre propeller blade A.7 Carbon fibre propeller blade with inhomogeneous internal structural foam core A.8 Triangular cross-section fuselage A.9 Hinged tail with landing skid A.10 Propeller blades align with the wing direction prior to landing 11 Attorney Docket No.391529.00003 A.11 Very fine flight control A.12 Combining heat shrinkable and non-heat shrinkable films A.13 Creating the wing skin Key Feature Group B: PVs B.1 Flexible PV film wing surface B.2 Flexible PV film with lacquer coating Key Feature Group C: Imaging systems C.1 Metallised carbon fibre lens C.2 Phased array antenna or sensor coated directly onto a wing skin C.3 Parallel processing of wing mounted imaging sensors Key Feature Group D: Connectivity D.1 Ground station connectivity D.2 Data payloads are sent plane-to- plane Key Feature Group E: Launch and recovery E.1 Plane with detachable propulsion pod E.2 Tail-first vertical lift and then nose-down release E.3 Plane lands on an autonomous vehicle E.4 Ground handling vehicle can move in any direction Key Feature Group F: Use cases F.1 Improved training of AI based models F.2 Improved inference for AI based models F.3 Combining multiple sensors or imaging subsystems 12 Attorney Docket No.391529.00003 F.4 Dark vessel monitoring F.5 Spy balloon capture F.6 Non-GPS location system F.7 Weather / Wind data capture process F.8 Urban Eyes F.9 Parking F.10 Traffic / movements F.11 Buildings F.12 Insurers, Finance, Service providers F.13 Plane includes sensors for geophysical surveys Note that any of the Key Features can be combined with any one or more other Key Features; any of the optional features for a Key Feature can be combined with any one or more other Key Features or with any one or more other optional features. Key Features Feature Group A: Design of the plane A.1 Modular construction HAPS, solar gliders, and other high altitude solar powered platforms are capable of flight missions lasting from several days to several months duration before they need to land to have their battery packs replaced, as well as to have a general service to keep all of their systems operating reliably. It is beneficial to minimise the time taken for a service so that the platform can be returned to revenue generating operations as quickly and efficiently as possible. But with conventional designs, repairing damaged, worn or tired sections of the plane can be very time-consuming. The Solaris plane is constructed from a number of modular sections e.g. central, inboard, outboard, wing-tip sections and winglets, fuselages, booms, vertical stabilisers and tail planes, any of which can be swapped out and replaced during servicing. This “swap-ability” enables rapid replacement of damaged, worn or tired sections, thus reducing service turnaround time. 13 Attorney Docket No.391529.00003 The swap-ability also allows sections of differing wing areas, fuselage / booms of different lengths, diameters (or widths) or different payload fitments to be incorporated, thus changing the flight characteristics between mission to suit different applications. For example, fitting wing sections with larger areas would increase the overall lift, permitting heavier payloads to be carried. Conversely reducing the wing area would increase the manoeuvrability of the plane, permitting tighter turn radii for more complete data capture when flying sensors with narrow swath widths. Lengthening the fuselages / booms would change the mass distribution to offset the mass of a forward mounted payload. Altering the length of the fuselage booms may also be used change the mass distribution to match the mounting mass and location of a payload – e.g. a forward mounted payload could be compensated for with a longer fuselage boom. One example: The plane is made up of a number of wing sections fitted to one or more central sections (also acting as a lifting surface). All of these sections are modular and replaceable; for example, a short wing section (e.g.1m in length - i.e. in the direction of wingtip to wingtip and not the chord dimension) and sitting in-between a pair of booms or fuselages, could be used for a small payload whereas a 2m long central section could be used for a larger or heavier payload. The left side wing (for the '28m' variant) is made up of two modular sections; likewise for the right side wing. A simple and light weight universal joint system is used to connect these modular, structural sections together. Modularity can also be used to design into the airframe specific failure points, minimizing the time to turn around by swapping out modular parts. Figure 1A shows the Solaris plane 1, comprising two wing sections 11, and a central section 12. The central section is positioned between two fuselages 13. Winglets 16 are provided at the tip of each wing sections. The winglets are downward facing, and act as landing skids in order to protect from ground damage when landing. A vertical stabiliser 14 and a horizontal stabiliser 15 are located at the end of each fuselage. A propeller blade 17 is also located at the front of each fuselage. 14 Attorney Docket No.391529.00003 Each section is modular and can be attached to or detached from the rest of the plane. Hence any section that is damaged can be easily replaced. Sections can also be substituted to tailor the plane's performance depending on an intended mission. For example, wing sections may be designed with different spans or taper ratios or materials. Figure 1B shows an exploded view of the Solaris plane showing the separate detachable sections: each wing section 11 can be attached and detached from a fuselage 13. The central section 12 can be attached and detached from each fuselage 13. Each winglet 16 can be attached and detached from a wing section 11. Each vertical stabiliser 14 can be attached and detached from the fuselage 13. Each horizontal stabiliser 15 can be attached and detached from a fuselage 13. A simple and light weight universal joint system 21 is used to connect the different sections together. The joint system is also easily replaceable and includes one or more of the following: tongue and groove; mortise and tenon; half-lap; biscuit; pocket; dovetail; rabbet; spigot; sliding tube. One type of joint system is used to attach two main structural sections together, as shown in Figures 2A - M: a lightweight but rigid bracket 22 is fixed to one section 25 (e.g. a post used for the vertical stabiliser) and that is shaped to receive and locate against a second section 26 (e.g. the long cylindrical section that forms a fuselage); the second section 26 is located against the bracket 22 and a loop of strong tape or fabric 27 is used to attach the second section 26 to the bracket 22. This approach is low cost, does not require a high skill level and enables sections to be rapidly attached to each other when preparing a plane for flight and also and rapidly detached from one another after flight. In Figure 2A, the bracket 22 is shown: it is rigidly attached to structural section 25: section 25 is the rigid cylindrical section that supports the vertical stabiliser 14. Bracket 22 includes a curved face 23, shaped to receive the second section 26, which is the rigid fuselage cylindrical section that forms the boom or fuselage. Figure 2B shows the second section 26 securely attached to the bracket 22, and hence the first section 25 using a loop of fabric 27, which is tightened using a tourniquet pin 28. 15 Attorney Docket No.391529.00003 Figure 2C shows the vertical stabiliser 14 attached to vertical structural section 25; the bracket 22 is secured to longitudinal, fuselage 26. A similar bracket 22 is used to attach longitudinal, fuselage 26 to a structural section passing through horizontal stabiliser 15. Figures 2D - 2F show the build sequence for attaching structural sections using the bracket 22. Figure 2D shows the bracket 22, with circular aperture 24 in the curved mounting surface 23. Fuselage or boom 26, shown in Figure 2E, includes a cylindrical boss or stub 29 that locates into circular aperture 24 when the spar 26 is correctly located against the mounting surface 23 of the bracket 22. Figure 2F shows the tape or fabric loop 27. Figure 2G shows the loop 27 in position on the fuselage or boom 26. Figure 2H shows how the loop is passed through the bracket 22 once the fuselage 26 has been located against the bracket 22. Figure 2I shows the tape loosely wrapped around the fuselage 26, with a loop section of the tape easily accessible. Next, as shown in Figure 2J, a tourniquet pin 28 is inserted behind the tape 27 at the tape end that does not include the loop. The pin 28 is twisted to tighten the tape 27, securely drawing in the fuselage 26 against the bracket 22. In Figure 2L, the loop in the tape 27 is teased open with a screwdriver and then, as a final stage, shown in Figure 2M, one end of the pin 28 is inserted into the loop in tape 27 to prevent the pin from unwinding. Overall, this is a very low cost, low-skill, lightweight and robust way of attaching different parts of the plane together; the loop can be readily loosened and unwound if the parts need to be separated (e.g. to replace a damaged vertical or horizontal stabiliser). Whilst we have shown this being used to attach the fuselage 26 to the vertical stabiliser 14 and also to the horizontal stabiliser 15, the same bracket-based system can be used wherever sections need to be securely and rapidly attached or quickly removed after landing. All elements in the airframe, including all of the modular elements, can be connected with one or more tethers, such that if there is a failure of the airframe, all of the elements will stay together; the entire airframe, made up of disconnected parts attached by these tethers, can be designed to descend like a sycamore leaf, with a reduced decent rate, keeping the parts together and reducing the danger of heavy items (e.g. batteries, payload) detaching and risking serious damage on the ground. Kinetic energy risk is hence reduced because the Solaris airframe is configured to a) distribute its mass across the widest section of the wings to minimize there 16 Attorney Docket No.391529.00003 being any single heavy section at risk (such as in single fuselage designs in which all of the payload and batteries are in the fuselage) and b) stay together if the airframe fails, to provide as much air braking as possible on descent. Combined, they reduce the kinetic energy risk of all parts of the platform. We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere, that includes at least one or more structural sections, each configured to be attachable, detachable and replaceable during normal servicing or operations. Optional features include any one or more of the following: ^ a replaceable structural section is a central wing section positioned between two fuselages ^ a replaceable structural section is an inboard wing section ^ a replaceable structural section is an outboard wing section ^ a replaceable structural section is a wing-tip section ^ a replaceable structural section is a winglet section ^ a replaceable structural section is a fuselage section ^ a replaceable structural section is a boom section ^ a replaceable structural section is a vertical stabiliser section ^ a replaceable structural section is a tail plane section ^ a replaceable structural section is a wing section, and different interchangeable wing sections have different surface areas ^ a replaceable structural section is a fuselage or boom, and different interchangeable fuselages or booms have different lengths (dimension in the direction of the long axis of the fuselage or boom) ^ different fuselages or booms have different widths (dimension in the direction perpendicular to the long axis of the fuselage or boom) ^ one or more sections are chosen to meet the specific payload requirements for a mission ^ one or more sections are chosen to meet the specific endurance requirements for a mission 17 Attorney Docket No.391529.00003 ^ one or more sections are chosen to meet the specific application or mission type, such as weather monitoring, earth observation and earth imaging, border security, maritime patrols, anti-piracy operations, disaster response and agricultural observation. ^ a wing section with a larger surface area is chosen where more lift is required ^ a larger central wing section is used for a heavier payload, compared with the central section used for a lighter payload ^ a wing section with a smaller surface area is chosen where more manoeuvrability, e.g. a tight turning radii, is required ^ a longer fuselage boom is chosen where a payload is more forward mounted. ^ a replaceable structural section is attached to another section or part of the plane using a mechanical joint ^ a replaceable structural section is attached to another section or part of the plane using a quick release mechanical joint ^ the mechanical joint is one or more of the following: tongue and groove; mortise and tenon; half-lap; biscuit; pocket; dovetail; rabbet; spigot; sliding tube. ^ joins between replaceable structural sections are designed as failure points. ^ multiple replaceable structural sections are secured together using a lightweight, rigid bracket that is fixed to one structural section and that is shaped to receive and locate against a second structural section; and where the second structural section is located against the bracket and a loop of strong tape or fabric securely attaches the second section to the bracket. ^ multiple replaceable structural sections are secured together using a tether so that they do not separate in the event of an airframe failure. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. A.2 Carbon fibre spar The concept of long duration, solar powered, high-altitude flight in the stratosphere relies on the aircraft being of exceedingly low mass. Apart from the batteries, one of the heaviest items is the airframe and a significant portion of this is the wing spar, which runs perpendicular to 18 Attorney Docket No.391529.00003 the fuselage(s). Making this wing spar as light as possible, whilst maintaining sufficient levels of both torsional and longitudinal stiffness, is key to producing a successful plane. In the Solaris plane, the wing spar is formed as a tube (e.g. a cylinder with a circular or elliptical cross section); the tube has carbon fibre inner and outer surfaces, between which is a structural foam core (e.g. a polymethacrylimide (PMI) based structural foam such as Rohacelltm). This is stronger and lighter than a solid carbon fibre tube or a carbon fibre tube with a square cross section. Different regions of the wing spar can have different mechanical properties, optimised for the specific forces or possible failure modes at that region. As an example, a denser structural foam core could be used locally in areas where additional strength is needed and / or extra carbon fibre can be incorporated locally. Similarly, intentionally designed-in weak points can be created by using a less dense core, or by varying the carbon fibre layering. Such a wing spar can also have non-uniform properties specifically to suit the flight characteristics of the particular aircraft and its function. Figure 3A shows a perspective view of the wing spar 31 formed as a tube. A cross section view of the wing spar at Figure 3B shows the carbon fibre inner 33 and outer 32 surfaces, between which is a structural foam core 34. We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere, that includes a light-weight structural section, formed as a tube with a circular or elliptical cross section, with carbon fibre inner and outer surfaces, between which is a structural foam core. Optional features include any one or more of the following: ^ the structural section is a wing spar ^ the structural section is a fuselage 19 Attorney Docket No.391529.00003 ^ different regions of the tube have different cross-sectional geometries to create different properties ^ the structural foam core is a polymethacrylimide (PMI) based structural foam ^ different regions of the structural section have different mechanical properties, optimised for the specific forces or possible failure modes at that region. ^ where additional strength is needed then a denser foam core and / or extra carbon fibre is used locally ^ intentionally designed-in weak points are created by using a less dense core, and / or by varying the carbon fibre layering. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. A.3 Downward winglet that acts as landing skid In order to keep the mass of the Solaris plane as light as possible, it is not desirable to incorporate landing gear or wheels that would be flown for many days but are only needed to work for a few minutes on landing. The Solaris plane instead uses an ultra-light weight solution to minimise damage on landing. In the Solaris plane, winglets are provided to optimise the aerodynamic properties of the aircraft and in one variant are downward facing as this permits them to also act as landing skids, protecting the underside of the wings from ground damage when landing. The winglet base can include a sacrificial material (e.g. light XPS foam) that contacts the ground but can easily be replaced during servicing. Figure 4A is a perspective view of the Solaris plane, indicating a detail or feature (A) at the base of a vertical stabiliser and another detail or feature (B) at the base of the downward facing winglets. Figure 4B is a perspective view of the detail (A) at the base of the vertical stabiliser. Figure 4C is a perspective view of the detail (B) at the base of the downward facing winglets. Figure 5A is a frontal view of the Solaris plane; Figure 5B is a side view of the Solaris plane indicating a detail (D) at the base of the vertical stabiliser and a detail (C) of the base of the downward facing winglets. Figure 5C is a side view of the detail (C) at the base of the 20 Attorney Docket No.391529.00003 downward facing winglets and Figure 5D shows a side view of the detail (D) at the base of the vertical stabiliser. The base of each vertical stabiliser includes a skid 51 made of a sacrificial material. The base of each winglet also includes a skid 52 made of a sacrificial material. The dimensions of the skids may be dependent on the size of the plane. We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere, that includes downward facing structures, such as winglets and / or a vertical stabiliser, that are also configured to act as landing skids. Optional features include any one or more of the following: ^ the downward facing winglets are configured to protect the underside of the wings from ground damage when landing. ^ the downward facing vertical stabiliser is configured to protect the underside of the fuselage or the rear horizontal stabilisers from ground damage when landing. ^ the base of each winglet or vertical stabiliser includes a sacrificial material that contacts the ground ^ the sacrificial material is a light XPS foam. ^ the sacrificial material is configured to be replaceable during servicing. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan ^ A.4 Battery re-positioning for optimal balancing Conventional aircraft undergo mass distribution changes as they burn their liquid fuel during flight. This is compensated by control surface inputs, however these increase the drag and reduce the flight efficiency. A solar powered plane maintains constant mass distribution throughout its flight since no liquid fuel is burnt, and so compensatory control surface inputs 21 Attorney Docket No.391529.00003 are not required, provided the mass distribution is correct at take-off. This feature is a way of achieving optimal mass distribution prior to flight. In the Solaris plane, the rechargeable Li-ion batteries are one of the heaviest items in the aircraft and are distributed along the length (i.e. perpendicular to the long axis of the plane) of the wing (e.g. the central wing 12, and also the main, dihedral wings 11, generally in the forward part of the wing; the Solaris plane includes an easy way to mechanically adjust their fore / aft location (e.g. manual millimetric adjustments of position) to give optimal balancing of the aircraft for different payloads. Battery packs are mounted on a lightweight frame and their position on the frame can be manually altered when the frame is being prepared for flight. Lateral adjustments port / starboard may also be provided to balance the total loading when taking into account other equipment that may not be symmetrically loaded (sensors, avionics, transponders, etc…) and to improve the overall flight stability which improves the quality of data capture. Vertical adjustments of the battery pack are also possible; any adjustment type (fore / aft; lateral; vertical) can be done independently of any other adjustment type. Figure 6A shows a battery pack 61 positioned along the length of wing 11 or 12 in a fully aft position across two adjacent wing ribs 62. The batteries may be rechargeable li-ion batteries and may generally be positioned in the forward part of the wing. The battery pack engages with mechanical adjustments 63 in adjacent wing ribs 62 that enables fore and aft adjustments of the battery pack. Each of these ribs 62 includes a frame 63 that enables multiple different positions that the battery pack can be positioned on or against. The battery pack 61 is inserted through one or more lock collars 64. The lock collar 64 engages with teeth or features located in the frame 63 in a wing rib 62. Whilst Li-ion rechargeable batteries are normally used, other high power-to-weight technologies (e.g. solid-state) may also be used. Each wing can include multiple battery packs 61, each housed in a foam covered leading edge of the wing; the foam covering is detachable from the wing ribs, exposing the batteries and enabling quick battery replacement / swaps. The foam covering also provides some thermal protection (e.g. from extremes of external temperature) and hence enhanced regulation for the batteries. We can generalise to: 22 Attorney Docket No.391529.00003 A solar powered plane, such as a plane configured to operate in the stratosphere, and that includes batteries or one or more battery packs that are configured to be positioned pre-flight in a battery position adjustment system to give an optimal mass distribution to offset or compensate for the mass and position of different payloads. Optional features include any one or more of the following: ^ the battery position adjustment system is positioned in a wing ^ the battery position adjustment system is positioned in a central wing positioned between twin fuselages ^ the battery position adjustment system is positioned in a dihedral main wing ^ the battery position adjustment system enables fore and aft adjustments. ^ the battery position adjustment system enables port / starboard lateral adjustments. ^ the battery position adjustment system enables vertical adjustments of the battery pack. ^ any adjustment type (fore / aft; lateral; vertical) can be done independently of any other adjustment type. ^ the battery position adjustment system is attached to or forms part of a wing rib ^ the battery position adjustment system includes a frame with multiple different positions that the batteries or one or more battery packs can be positioned on or against. ^ the battery position adjustment system includes a locking collar configured to lock the battery at a desired position relative to a wing rib. ^ the battery position adjustment system is located in a leading edge of the wing ^ the battery position adjustment system is located behind a removable part in a leading edge of the wing, and the battery or battery pack can be inserted, removed and its position adjusted once the removable part has been removed. ^ the removable part includes a foam layer ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. A.5 Batteries and payload positioned in the wings 23 Attorney Docket No.391529.00003 As noted above, in a Solaris plane, the batteries can be placed in the wings, as opposed to the fuselage (e.g. in the central wing 12 and / or the dihedral main wings 11). By placing the heavy batteries in the dihedral main wings, we also reduce or dampen fluctuations that can stress the wing spar. By distributing mass of these non-airframe items across the dihedral main wings, as opposed to placing that mass in the fuselage, we also reduce the loading on the joints between the dihedral main wings and the fuselage. The principle of placing items into the dihedral main wings applies not just to batteries, but other non-airframe items too, such as payload sensors, avionics, communications equipment; for many of these items, there are functional advantages to being positioned in the dihedral wings: for example, stereoscopic imaging sensors benefit from being placed towards the wingtips. The non-airframe items can be positioned in or against a holder or attachment system that is itself fixed to the airframe (e.g. the wing ribs or wingspar - (see A.4 above) and that enables the non-airframe item to be rapidly attached to and removed from the airframe. These items can be positioned in a foam covered leading edge of the wing; the foam covering is detachable from the wing ribs, exposing the batteries, payload, avionics etc and enabling quick replacement / swaps. The foam covering also provides some thermal protection (e.g. from extremes of external temperature) and hence enhanced regulation for the items positioned in the wings. We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere, and that includes one or more non-airframe items positioned inside the dihedral wings. Optional features include any one or more of the following: ^ the non-airframe item is a holder or attachment system configured to releasably secure the non-airframe item in position. ^ the non-airframe item is a battery ^ the non-airframe item is a sensor 24 Attorney Docket No.391529.00003 ^ the non-airframe item is an antenna ^ the non-airframe item is an avionics system ^ the non-airframe item is a communications system ^ the non-airframe item is located in a leading edge of the dihedral wing ^ the non-airframe item is located behind a removable part in a leading edge of the dihedral wing, and the non-airframe item can be inserted, removed and its position adjusted once the removable part has been removed. ^ the removable part includes a foam layer ^ the plane is a twin fuselage plane and includes one or more non-airframe items positioned in a central wing joining the two fuselages. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. A.6 Over-sized foam core used in the carbon fibre propeller blade For a solar powered HAPS propellor, efficiency is important. Assuming a good design, both the accuracy of the propellor shape and its high quality surface finish are key. In order to achieve a reliable and repeatable process, the propeller blade(s) in the Solaris plane are manufactured as follows: The propeller blade is made using a compression moulding press into which bespoke, highly polished top and bottom cavity moulds of the propeller are fitted to the heated platens of the press. The pre-cut, pre-impregnated layup of carbon fibre sheets for one side skin of the blade is laid into the lower half of the mould followed by a pre-machined over-sized foam core; this core has a surface that is approximately 0.5mm higher than it would normally be in a conventional process. Since the carbon fibre sheets are typically no more than 0.2mm in thickness and the total thickness of the blade is typically no more than 10mm, this additional volume of the foam core is significant. The over-sized core is then covered with the second carbon fibre outside skin. The press is closed, crushing the outer surface of the over-sized foam core and squeezing out any bubbles or wrinkles in the carbon skins. The platens are maintained at the appropriate process temperature until the pre-impregnated carbon fibre sheets have set. The pre-finished item is then released from the mould for final finishing. Because any bubbles and wrinkles are squeezed out since the entire surface of the blade is compressed by approximately 0.5mm, the 25 Attorney Docket No.391529.00003 quality of the blade surface is very high: a much smoother, high quality finish than would be the case if an over-sized foam core was not used. We can generalise to: A carbon fibre structure for a system, the structure made using a vacuum / compression moulding process, with carbon fibre pre-impregnated sheets formed in a mould around an over- sized structural foam core. Optional features include any one or more of the following: ^ the over-sized structural foam core is sized so that one or more surfaces of the core are compressed down by at least 0.2mm during the moulding process. ^ the over-sized structural foam core is sized so that one or more surfaces of the core are compressed down by approximately 0.5mm during the moulding process. ^ the over-sized structural foam core is sized and shaped so that, when a press is closed over the carbon fibre pre-impregnated sheets, then at least some of the surface of over- sized structural foam core is crushed or compressed, squeezing out some or all bubbles or wrinkles in the carbon fibre pre-impregnated sheets. ^ carbon fibre pre-impregnated sheets for one outside side skin of the structure are laid into a lower half of a mould, followed by a pre-machined over-sized foam core, which is then covered with the second carbon fibre outside skin and the press is then closed to compress two halves of the mould together. ^ the system is any device over which smooth air or fluid flow is desirable. ^ the system is solar powered plane, such as a plane configured to operate in the stratosphere ^ the structure is a propeller blade ^ the structure is a strut or spar ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. 26 Attorney Docket No.391529.00003 A.7 Carbon fibre propeller blade with inhomogeneous internal structural foam core The concept of long duration solar powered high altitude flight in the stratosphere relies on the plane being of exceedingly low mass. In order to keep the mass as low as possible the propulsion system and the propellers need to operate outside of their optimised efficiency envelope, particularly in the lower stratosphere. This feature A.6 maximises propeller structural performance with minimal mass increase. In the Solaris design, different regions of the propeller blade can have different types or structures of internal foam core with mechanical properties optimised for the specific forces / possible failure modes at that region. The variable properties in the core make it possible to reduce mass and / or to vary the stiffness or flex of the finished component. As an example, a light weight honeycomb core could be used to reduce mass in areas of the propeller blade where less strength is needed; we machine a pocket in the foam core and insert some light weight honeycomb into that pocket. Conversely specific inserts (e.g. carbon fibre tubes, extra laminate or denser foam) can be locally incorporated where extra strength or rigidity is required; for example, near the root of the blade we need to transmit a lot of torque from out across the width of the blade so we could again make a pocket but insert into it extra carbon, or Kevlar fibres, or even pre-formed composite stiffeners before the blade has its skins attached. The propeller blades of the planes may be selected depending on several design parameters, such as weight, efficiency or operating conditions of the solar powered plane. Different types of propeller blades with different types or structures of internal foam core may be selected, as shown in Figures 7-9. Different regions of the blade may need more enhanced structural performance, such as strength and stiffness, while minimising weight. The internal foam core provides structural support and helps maintain the blade’s shape in operation. Figure 7 - 9 shows different views of a propeller blade with a honeycomb core. In Figure 7 the leading edge that is subject to high aerodynamic loads and forces is made of a high-density foam core 71. The trailing edge is made of a low-density foam core 72. The internal section of the blade includes a pocket filled with light weight honeycomb 73. Further, the external contour 27 Attorney Docket No.391529.00003 of the blade may include additional reinforcement 74. Figure 8 is a cross sectional view through the blade along section A - A. Figure 9 is a perspective view of the blade. Figure 10A show different views of another propellor blade with a different internal structure that includes one or more pockets 81 or cavities that are designed to fine tune the structural properties of the blade. Inserts made of materials such as carbon fibre tubes, extra laminate, or denser foam, are then embedded within the one or more pockets 81 to provide additional structural support and help distribute the load more effectively, especially in region experiencing higher stresses or where increase strength or rigidity is desired. The inserts combined with the foam core create a composite structure that is selected based on the desired performance characteristics of the propeller blade. The root of the blade may include an insert 81 (as shown in plan view in Figure 10A), to provide extra stiffness, such as extra carbon, or synthetic fibre such as Kevlar fibre, or even pre-formed composite stiffeners. This is because the root of the blade needs to be robust to transfer a lot of torque effectively. Figure 10B is a cross section along line A - A in Figure 10A and Figure 10C is a cross section along line B - B in Figure 10A. Figure 11A shows the Figure 10 blade in plan view, but showing the lightweight, low-density honeycomb foam core 73 that is also present. Figure 11B is the blade in perspective view; Figure 11C is a cross-section along A - A, showing the internal lightweight core and Figure 11D is a close up view of region B indicated in Figure 11B. We can generalise to: A carbon fibre structure for a solar powered plane, such as a plane configured to operate in the stratosphere, in which the structure comprises an outer carbon fibre shell enclosing an internal structural foam core together with a second material with a different mechanical property to the internal structural foam core or the carbon fibre shell. Optional features include any one or more of the following: ^ the structure is a propeller blade 28 Attorney Docket No.391529.00003 ^ the structure is a strut or spar ^ the second material is optimised for specific forces ^ the second material is optimised for specific possible failure modes ^ the second material is also a foam core, but of different density to the internal structural foam core ^ the second material is a non-foam material ^ the second material is made of carbon fibre, synthetic fibre, composite, laminate, or a dense foam. ^ the second material provides increased strength or rigidity to the structure ^ the second material is extends form the root of a propeller blade into the body of the propeller blade ^ the internal structural foam core is a lightweight, honeycomb foam core used to reduce mass in areas of the structure where less strength is needed. ^ the second material is an insert that is inserted into a void or space in the internal structural foam core, and the insert is configured to provide specific mechanical properties. ^ the insert (e.g. carbon fibre tubes, extra laminate or denser foam) are locally incorporated where extra strength or rigidity is required. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. A.8 Triangular cross-section fuselage Solar powered unmanned HAPS, etc. with solar cells on the upper surfaces of the wing can suffer the effects of reduced angles of solar incidence when flying into the sun or at 90 degrees to the sun. The Solaris plane adopts a triangular fuselage; each fuselage is covered on the two upward facing surfaces in solar cells. This helps to mitigate some of these effects by adding extra solar cells at a different angle to those on the wing. So in the Solaris plane, the fuselage (or each fuselage in a twin or multi fuselage plane) has a triangular cross-section (e.g. equilateral or isosceles) with the apex at the top; it is made of carbon fibre struts covered in a stretched Mylar (or other plastic, e.g. polyester film) skin with integral PV cells on the two upward facing surfaces. 29 Attorney Docket No.391529.00003 Figure 12A shows a perspective view of a triangular fuselage formed with a triangular cross- section, such as equilateral or isosceles, with its apex at the top. Figure 12B shows a cross- section through this triangular fuselage. Solar cells 90 are included on, or form part of, each upward facing planar surface of the fuselage. We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere and including at least one fuselage with a substantially triangular cross-section with apex at the top, and in which an array of PV cells is formed on at least part of the two upward facing surfaces of the fuselage. Optional features include any one or more of the following: ^ the plane includes two fuselages, each formed with a triangular cross-section with its apex at the top, and an array of PV cells is formed on at least part of the two upward facing surfaces of each fuselage ^ the surface of each fuselage comprises a stretched plastic, e.g. polyester, film skin with integral PV cells ^ the fuselage is isosceles in cross-section ^ the fuselage is equilateral in cross-section ^ the plane includes further PV cells on the upper surface of one or more wing sections ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan A.9 Hinged tail with landing skid In the Solaris plane, the fuselage or fuselages include a vertical tailplane (i.e. vertical stabiliser) that extends both above the fuselage, and also below the fuselage. The base of the vertical tailplane includes a sacrificial strike point and a landing skid (see Feature A.3 above). The vertical tailplane is hinged so that when the skid contacts the ground on landing, the top of the vertical tailplane pivots forwards around the hinge point, allowing the entire aircraft to belly 30 Attorney Docket No.391529.00003 flop onto the runway, whilst minimising damage to the aircraft on landing. This pivoting of the rearmost skid avoids high bending moments being generated in the fuselages / s. During flight, the vertical tailplane is prevented from hinging by means of either a frangible pin or lashing. The strike point & landing skid can, as noted above, include a lightweight sacrificial layer (e.g. XPS foam). Figure 13A is a perspective view of the Solaris plane in normal flight; the vertical tailplane 14 is upright. Figure 13B is a perspective view of the Solaris plane during landing; the vertical tailplane 14 has been hinged forwards as the skid at the base of the tailplane has contacted the ground. Figure 14A shows a side view of the Solaris plane; the vertical tailplane in the expanded circular window is shown upright, the normal flight position, and also hinged forwards, which is the position it takes during landing . The base of the vertical tailplane 14 includes a sacrificial strike point and a landing skid and is hinged so that when the skid contacts the ground on landing, the top of the vertical tailplane pivots forwards around the hinge point, allowing the entire aircraft to belly flop onto the runway, whilst minimising damage to the aircraft on landing. Figure 14B shows a detail side view of the vertical tailplane 14 positioned during flight 121 and when landing 122. When landing the vertical tailplane pivots forward around the hinge point 123. This pivoting of the rearmost skid avoids high bending moments being generated in the fuselages / s. We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere and including a hinged vertical stabiliser that that pivots about a hinge, and where the stabiliser extends both above the fuselage and also below the fuselage, and the base of the vertical stabiliser includes a skid. Optional features include any one or more of the following: 31 Attorney Docket No.391529.00003 ^ the hinged vertical stabiliser is configured such that when the skid contacts the ground on landing, the top of the vertical stabiliser pivots forwards around the hinge point, minimising damage to the aircraft on landing ^ the skid includes a lightweight, replaceable sacrificial layer ^ the vertical stabiliser is prevented from hinging during normal flight by means of either a frangible pin or lashing ^ the plane includes downward facing winglets and these also act as landing skids ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan A.10 Propeller blades align with the wing direction prior to landing In the Solaris plane, the plane glides in to land; none of the propeller blades are powered for a significant portion of the landing descent, and are instead automatically turned to be in-line with the wings, to minimise risks of being damaged on landing. The motor is fitted with a sensor that detects the position of the propellor. And the motor controller can step the motor rotation until the propellor is aligned and held horizontally (or with the wing direction, e.g. for a dihedral or anhedral wing). Alternatively, a sensor can determine when the propeller blades are in-line with the wings and to immediately short-circuit the motor to cause the blades to stop at the in-line position. Turning the propellers to be in-line with the wings is especially useful when the plane is landing on a moving autonomous ground platform or AGP (see Feature E.3 below); it is critical to avoid the blades from colliding with the AGP. There may be a sensor in the plane and / or AGP to enable accurate relative positioning of the plane and AGP; data from this sensor can also be used to stop the propeller blades when they are in-line with the wings. For instance, the sensor can detect when the plane is say 2m above the AGP, or within 5 seconds prior to landing on the AGP, and the sensor can then generate a signal that causes the propeller motors to immediately cease. We can generalise to: 32 Attorney Docket No.391529.00003 A solar powered plane, such as a plane configured to operate in the stratosphere, in which the plane includes, or receives data from, a sensor configured to detect the approach of the plane to an autonomous ground platform (AGP) on which the plane is designed to land; and in which the sensor is further configured to generate a signal that is used to control the propeller blades to be in-line with the wings of the plane when the height of the plane above the AGP and / or its rate of descent to the AGP or the time to landing on the AGP meet defined criteria. Optional features include any one or more of the following: ^ data from the sensor is used to enable accurate relative positioning of the plane and the AGP. ^ the sensor is in the plane, or the AGP, or is distributed between the plane and the AGP. ^ the blades are also automatically turned to be in-line with the wings prior to landing on the ground, the sensor is configured to detect the approach of the plane to the ground. ^ the motor or motors driving the or each blade are shorted to stop the propeller blades when they are be in-line with the wings. ^ each propeller motor is fitted with (i) a position sensor that detects the position of the propellor and (ii) a motor controller configured to rotate or step the motor rotation until the propellor is aligned substantially horizontally. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. A.11 Very fine flight control One of the big uses of HAPS is for data capture. In order to maximise the accuracy of this data capture, flight stability and fine flight control of the HAPS is essential. For flight at high altitudes where the air density is low, HAPS require large control surfaces which move relatively slowly. But to fine tune the flight stability, small very fast acting surfaces would be preferable; these could be on the tail which would in theory enhance their leverage by being further form the centre of lift, however extra mass on the tail is very disadvantageous on HAPS, not least as the control surfaces would require long wiring runs which add to the mass. If mounted on the tail they also lose some effect due to the natural damping caused by the flex of the fuselage / boom or booms. 33 Attorney Docket No.391529.00003 The Solaris plane uses small control surfaces (e.g. trim ailerons) that are located adjacent to, but behind (and optionally below), the main wing; this has several advantages, including keeping the extra mass of the surfaces as close to the fore-aft CofG (centre of gravity) as possible. Another advantage is that being located under the wing they produce secondary aerodynamic effects which enhance their functionality and reduce the amount that they need to move in order to maximise the flight control and stability of the HAPS. Because the main wings have no moving parts, such as control surfaces, this simplifies the design, build and cost of fabrication. It also improves the aerodynamics for lift and stiffness of the airframe and enables load (batteries, payloads, avionics, communications payloads etc) to be spread widely across the wing section, (especially the central wing section in a twin fuselage plane like Solaris) improving airframe stiffness and flight stability, delivering a superior platform for data gathering. The twin motor design enables differential power to be applied to each propeller motor, to cause a flat turn, i.e. one in which no bank or pitch is required, enabling a far superior platform for data gathering, communications links (e.g. optical); because it reduces the need for mechanical steering of sensor lenses, communications transmit / receive antenna / lensing, and enables controllable timing for precise flight patterns and / or formation flying for multi- instrument or very wide aperture data gathering. In a turn induced by applying differential power to the two motors, the small control surfaces may not be used at all, or used in a way that enables the flat turn to be achieved. Figure 15 is a top-down view of the plane, showing the small control surface (e.g. trim ailerons or controls) 131 that are located behind the main wing. Figure 16A is a perspective view of the plane, showing the trim ailerons or controls 131 that are located behind the main wing and Figure 16B is a close up view of these trim ailerons or controls 131. Figure 17 is a side view of these trim ailerons or controls. 34 Attorney Docket No.391529.00003 We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere, including movable control surfaces extending from a fuselage of the plane and positioned adjacent to, but behind the main wings of the plane. Optional features include any one or more of the following: ^ movable control surfaces are positioned adjacent to, but behind and below, the main wings of the plane ^ the main wings include no moving parts or control surfaces ^ the plane is a twin fuselage plane and at least some of the plane's payload is distributed in some portions of the central wing between the two fuselages ^ at least some of the plane's payload is distributed in some portions of the main wings ^ the pane has twin fuselages, each with a motor driving a propeller, and is configured for differential power to be provided to each motor to enable a substantially flat turn to be achieved in conjunction with the control surfaces. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan A.12 Combining heat shrinkable and non-heat shrinkable films Some types of plastic films like Mylar come in heat-shrinkable variants and these are conventionally used to form the wings and other surfaces of HAPS; the film is wrapped over the underlying support structures and heat is applied to shrink and tension the film. In the Solaris plane, we use both heat-shrinkable and non-heat-shrinkable films so that we can integrate structures that cannot be shrunk into the skin of the plane: for example, we can form structures on non-heat-shrinkable films into sheets and we join the edges of these sheets to a heat-shrinkable plastic film border to form a panel; we can join adjacent panels together and these panels can form the skin of a wing or fuselage; the panels can be attached to the underlying structure. By heating these panels, we can secure the panels to the frame of the plane and also stretch and tension the entire surface formed by these panels. By 'heat- shrinkable' we mean a material that reduces in a linear dimension by at least 5% under heat. 35 Attorney Docket No.391529.00003 Examples of the structures that are not heat-shrinkable are PV panels (see also B.1 Flexible PV (photo voltaic) film wing surface) and phased array antennas (see C.2 Phased array antenna or sensor coated directly onto a wing skin). The surface of each fuselage may comprise a stretched plastic, e.g. polyester, film skin with integral PV cells. Figure 18 shows a top view of a panel made up of a non-heat-shrinkable film substrate 141 and a heat shrinkable border 140. The non-shrinkable film substrate integrates with electronic items. The non-heat-shrinkable film 141 may include integrated electronic items, such as PV cells. We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere, the surface of the plane comprising panels that are each made up of a sheet that includes a non-heat-shrinkable film substrate and a heat shrinkable border to the sheet, and in which these panels are joined or attached together to form part of a surface of the plane that is tensioned or tightened by heating the heat shrinkable border. Optional features include any one or more of the following: ^ the sheets include one or more PV films formed on a non-heat-shrinkable film substrate ^ the sheets include one or more antennas, such as phased array antennas, formed on a non-heat-shrinkable film substrate ^ the sheets include one or more mirrors ^ the surface that is tensioned or tightened forms a part of the wing and / or fuselage surface of the plane ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan 36 Attorney Docket No.391529.00003 A.13 Creating the wing skin The wings are manufactured in sections up to 8m in length and 2.5m cord. We need to apply a thin plastic, e.g. polyester film, like Mylar film, to create the wing-skin; this skin is therefore a very large but only a few microns thick piece of film and is very difficult to handle and to apply evenly without wrinkles across the entire wing surface. Once applied, we need to heat shrink the wing skin to a consistent tension. It is very hard to do this consistently. The solution is to build a light weight but relatively stiff frame that the skin can be unreeled onto; the frame has clips that allow the edges of the skin to be griped to the frame, and it is then easy to adjust the skin tension to remove all wrinkles, at which point the frame can be accurately positioned relative to a pre-glued wing structure before the skin is finally brought into contact and the adhesive bond is made wrinkle free. Consistent shrinking and tensioning is required. We accurately apply dots of (non-permanent) ink to the skin as it is unrolled from its reel on to the frame. We use real-time video images of the skin during the tensioning and shrinking process and by automatically comparing the distances between the dots we can ensure that the distances remains uniform. We can generalise to: A method of creating a wing-skin for a solar powered plane, such as a plane configured to operate in the stratosphere, comprising the steps of: (i) unreeling a heat shrinkable plastic film on to a frame; (ii) securing the film to the frame; (iii) applying heat to the plastic film to shrink it evenly; (iv) positioning the frame over a pre-glued wing structure; (v) bringing the plastic film into contact with the pre-glued wing structure. Optional features include any one or more of the following: ^ the heat shrinkable plastic film includes dots or other location markers at pre-defined positions 37 Attorney Docket No.391529.00003 ^ the heat shrinkable plastic film includes dots or other location markers at pre-defined positions and the method includes the step of monitoring the distances or positions of the markers during the heat shrinking process to ensure that shrinkage is uniform. ^ step of monitoring the distances or positions of the markers during the heat shrinking process is doing using a computer vision system ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan Feature Group B: PVs B.1 Flexible PV (photo voltaic) film wing surface In conventional stratospheric solar powered planes, the PVs are formed on a thin glass substrate and this substrate is then attached (e.g. glued) to the wing surface, which is made of a thin MylarTMor other plastic film stretched over the spar and ribs of the wing. In the Solaris plane, we take every opportunity to reduce mass; we use PV cells that are formed, not on a glass substrate, but instead on a thin Mylar plastic substrate. This Mylar substrate is then also used as the actual wing skin, with the plastic substrate of multiple adjacent PV cell panels joined together to form a contiguous, stretched wing surface. The plastic substrate to these PV panels is not heat-shrinkable; at the edges of these panels we use a heat-shrinkable plastic film and by heating this film we stretch and tension the entire wing surface (see Feature A.11 above). We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere, including PV cells that are manufactured on or integrated with a plastic film substrate and the plastic film substrate of multiple PV cells are joined together to form a part of the wing and / or fuselage surface. Optional features include any one or more of the following: 38 Attorney Docket No.391529.00003 ^ the joined plastic film substrates of the PV cells are formed into a stretched skin that forms at least part of the wing and / or fuselage surface ^ the plastic film substrates of the PV cells are non-heat-shrinkable ^ the plastic film substrates of the PV cells are attached at their edges to sections of a heat-shrinkable plastic film that are heated to form a tensioned surface ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan B.2 Flexible PV (photo voltaic) film with lacquer coating In the Solaris plane, the PV cells that are formed directly onto the Mylar plastic film are coated with a protective lacquer, e.g. the lacquer is applied over the untreated surface of the solar cells to protect the surface from moisture and corrosion. A proprietary thin film CIGS solar cells typically weighing less than 60g / m2is used. Such cells are normally encapsulated within an EVA film or envelope to protect them from moisture and corrosion. This typically adds 500 to 800g / m2. In the Solaris plane, the cells are instead protected for high altitude flight operations with an application of a thin layer of lacquer. This typically weighs less than 30g / m2, significantly reducing the weight of the protected cells. We can generalise to: A solar powered plane configured to operate in the stratosphere and including PV cells that are protected for high altitude flight operations with an application of a layer of lacquer. Optional features include any one or more of the following: ^ the PV cells are manufactured on or integrated with a plastic film substrate ^ the lacquer replaces an EVA film or envelope ^ the lacquer is applied to the PV cells using a sputter deposition process. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. 39 Attorney Docket No.391529.00003 Feature Group C: Imaging systems C.1 Metallised carbon fibre lens In the Solaris plane, an imaging system can be deployed that does not use a conventional and heavy glass lens but instead a reflecting telescope-type design in which the parabolic primary mirror (and optionally any secondary mirror if used) is a carbon fibre parabolic surface that has been sputter coated with a metallic, light reflecting coating. At the prime focus there is a conventional digital camera CCD. The cylindrical side walls of the reflector are carbon fibre too. This structure is much lighter (mass is approximately 50g) and cheaper than a glass-based lens; it has very low thermal mass, so reaches thermal equilibrium quickly without thermal-related distortions. It provides extreme magnification (1 pixel = 8cm ground sample distance) - that is equivalent to the far heavier and more expensive glass lens system used in other conventional HAPS. The focal length is optimised to image ground features when the plane is at 65,000 - 70,000 feet. Figures 19 - 21 show a different imaging system including a carbon fibre parabolic surface that has been sputter coated with a metallic, light reflecting coating. The cylindrical side walls are also made of carbon fibre. Different designs of parabolic surface are shown. We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere, and configured with an imaging system including a carbon fibre parabolic surface that has been sputter coated with a metallic, light reflecting coating. Optional features include any one or more of the following: ^ at the prime focus is a conventional digital camera CCD. 40 Attorney Docket No.391529.00003 ^ the cylindrical side walls of the reflector are carbon fibre. ^ the imaging system delivers approximately 1 pixel = 8cm ground sample distance ^ the focal length of the imaging system is optimised to image ground features when the plane is at stratospheric altitudes, such as 65,000 - 70,000 feet. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. C.2 Phased array antenna or sensor coated directly onto a wing skin In the Solaris plane, a phased array antenna can be applied, e.g. by sputter coating, directly onto the Mylar or other polyester or lightweight, dimensionally stable film, e.g. on a lower wing section. This gives a very large antenna array area (e.g.28m or 38m in length). Phased array antenna have many uses, including communications and synthetic aperture radar. A constellation of Solaris planes can fly together to create a synthetic aperture radar of even greater effective array size. The phased array antenna can be linear (e.g. SAR), grid (configuration determines the beams, shapes and bandwidths) or conformal (e.g. over a curved wing section or tail section or underwing flat surface). Their spacing, configuration varies with frequency (1 / 2 lambda), application and beam-forming strategy. The phased array can be part of an active and / or passive antenna system. It is not just phased array antennas that can be formed directly onto the stretched wing-skin: other types of sensors (potentially of different kinds), can also be formed on the wing surfaces, e.g. using a thin film technique. This is especially relevant for sensors that require large flat areas for interaction with the environment (chemistry, biology, physics) and electro-magnetic, nuclear or gravitational domains such as found in quantum sensing techniques. The sensors can be positioned on the lower wing surfaces for earth observation (e.g. earth surface and atmospheric analysis) and on the upper wing surfaces when looking away from the earth (e.g. stratospheric analysis, space observation, satellite observation, space debris re-entry observation). We can generalise to: 41 Attorney Docket No.391529.00003 A solar powered plane configured to operate in the stratosphere, and including an antenna and / or sensor formed directly onto a stretched plastic, e.g. polyester, film substrate to form part of the surface of the plane. Optional features include any one or more of the following: ^ the stretched film forms the lower or upper surface of a wing section or wing skin. ^ the antenna or sensor is formed directly onto the stretched film by a sputter deposition process ^ the antenna is a phased array antenna ^ the antenna is a phased array antenna configured for communications ^ the antenna is a phased array antenna configured for radar ^ the antenna is a phased array antenna that is linear or grid ^ the antenna is a phased array antenna that is conformal ^ the antenna is a passive antenna ^ the antenna is an active antenna ^ the sensor is positioned on the lower wing surfaces and is configured for earth and sub- stratosphere atmospheric observation. ^ the sensor is positioned on the upper wing surfaces and is configured for space, or above-stratosphere atmospheric observation. ^ adjacent film substrates of the antenna and / or sensor are joined together ^ the joined film substrates of the antenna and / or sensor are formed into part of a stretched skin that forms at least part of the wing and / or fuselage surface ^ the film substrates of the antennas and / or sensors are non-heat-shrinkable ^ the film substrates of the antennas and / or sensors are attached at their edge to sections of a heat-shrinkable film that is heated to form a tensioned surface. the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. C.3 Parallel processing of wing mounted imaging sensors 42 Attorney Docket No.391529.00003 One of the key parameters for data collection from HAPS platforms is the swath width (i.e. the width of the broad strip that can be imaged by the platform in a single pass). The Solaris plane is configured to process images from multiple sensors mounted along the wings, and to process these images, automatically compensating for wing flex, into one seamless image (either optical image or data) that covers a far wider swath than is possible with a plane using just a single sensor. The processing can be done in parallel using a local GPU in the plane, or using ground-based computing resources, or a combination, where some computing resources in the plane are part of an edge computing architecture. The group of cameras / sensors could also be mounted centrally and angled relative to each other to capture a much larger swath width than is possible with a plane using just a single sensor, again with powerful GPU processing the image to remove the distortion caused by the relative angle of the cameras / sensors to each other and to compensate for wing flex. We can generalise to: A solar powered plane, such as a plane configured to operate in the stratosphere, including multiple sensors configured to capture a swath width that is greater than the width that a single sensor could capture, and the plane includes a local processor, such as a GPU, configured to process at least some of the data from the multiple sensors into a single dataset covering the entire swath. Optional features include any one or more of the following: ^ at least some of the multiple sensors are mounted at different positions along a wing or wings ^ at least some of the multiple sensors are mounted in a fuselage ^ the plane is a twin fuselage place and at least some of the multiple sensors are mounted in each fuselage ^ at least some of the multiple sensors are oriented in different directions ^ one or more of the multiple sensors are mounted at different positions along the wings and the processor is configured to compensate for wing flex 43 Attorney Docket No.391529.00003 ^ one or more of the sensors are image sensors and the single dataset is an image covering the entire swath ^ local processor in the plane is part of an edge computing architecture ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan Feature Group D: Connectivity D.1 Ground station connectivity Small mobile ground receiving stations (potentially suitcase sized) can be moved to (or near to) a region that the plane (or planes) are surveying / analysing and then plane / s can then fly a loitering path (e.g. a circle) around the ground receiving station / s and transmit their data payload. Using a line of sight optical link to the ground receiving station / s for very fast (up to 100Gbps – coherent multi-colour) and high security data transfer is possible: from 20km the beam will be less than 1m in diameter and it is not possible to intercept this beam undetected, which makes it especially relevant for quantum key distribution. It is also very efficient - optical transceivers are light, and power efficient. Data transmission could be done at night if in the daytime the plane / s are surveying / analysing in visible light. The mobile ground receiving stations can complement, supplement or replace the use of conventional fixed ground receiving stations. Optical data links have demonstrated duplex communication with a speed of 10Gbps from 20km altitude to the ground; 100Gbps is potentially possible over large distances both in space (inter-craft) and through the atmosphere (ground to space). We can generalise to: A method of providing data connectivity for a solar powered plane, such as a plane configured to operate in the stratosphere, including the step of moving a mobile ground station to a defined location, and configuring the plane to fly a path that enables the plane to transmit data back down to the mobile ground station. 44 Attorney Docket No.391529.00003 Optional features include any one or more of the following: ^ the path is optimised to increase the reliability and / or speed of the data transmission ^ the plane uses a line of sight optical link to the ground receiving station / s for very fast (up to 100Gbps) and high security data transfer. ^ the optical link uses coherent light ^ the optical link uses coherent, multi-colour light ^ the data is used for quantum key distribution. ^ Data transmission is done at night if in the daytime the plane is surveying / analysing in visible light. ^ The mobile ground receiving stations can complement, supplement or replace the use of conventional fixed ground receiving stations. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. D.2 Data payloads are sent plane-to-plane Solaris planes can share their data payloads with one another (e.g. using a plane-to-plane optical link for security and efficiency), with the downlink to a ground receiving station then done by one of these planes. So there could be a constellation of Solaris planes over a large area, forming a mesh network, but perhaps not all can fly a path that enables them to transmit data reliably down to a ground receiving station; then, the planes share their data payloads from plane-to-plane; any plane able to transmit to ground (e.g. can fly a path that brings it into LoS - line of sight- with a ground receiving station) then does so, transmitting the data payloads sent to it from other planes. There could be multiple planes, each capable of independently sending data to ground, so there is redundancy. Solaris planes can also push data up to a satellite layer and from the satellite layer down to a ground station or ground-based receiver (and vice versa). Solaris planes can operate as a repeater for satellite layers so they can reach devices on the ground. For example, for LTE, a Solaris system can be the ‘last mile’ (or, more literally, the last 10 to 30 miles) in connecting a standard mobile phone to a global satellite network where 45 Attorney Docket No.391529.00003 the relative proximity of the Solaris planes enables sufficient power and the LTE protocol to work with every mobile device. Solaris planes can be a relay to / from either non-terrestrial and / or terrestrial systems for any of the uses defined in this specification. For IoT, Solaris planes can be the 'last-mile' repeater / transponder to cover the wide areas where IoT devices are located. Or in AIS (automatic identification system) or VDES (VHF Data Exchange System) where Solaris planes can be the repeater / transponder that extends the reach of the system across seas / oceans for continuous coverage, relaying each vessel’s data via a Solaris plane-to plane mesh network of solar gliders to all other AIS / VDES vessels and back to ports, coast guards and other authorities, or relaying this up via satellite networks to span large areas. The same can be applied to Solaris planes providing traffic, navigation, PNT (position, navigation and timing) and safety information services to manned and autonomous craft / vehicles by acting as the ‘last mile’ layer over wide areas. PNT services are potentially especially useful for autonomous vehicles, such as drones, farm equipment, remote sensing equipment, highway vehicles, ships). We can generalise to: A method of providing data connectivity using a solar powered plane, such as a plane configured to operate in the stratosphere, including the step of configuring the plane to send data to, or receive data from, one or more different solar powered planes, and for one or more of those different planes to transmit data to, or receive data from, a ground station or other ground based system, or a satellite. Optional features include any one or more of the following: ^ a plane-to-plane free-space optical link is used ^ a group of planes is formed over a large area, where not all can fly a path that enables them to transmit data down to a ground receiving station and then, one or more planes in the group share their data payloads from plane-to-plane, with any plane able to 46 Attorney Docket No.391529.00003 transmit to ground then doing so, transmitting the data payloads sent to it from other planes. ^ the method enables a mobile phone or an IoT device to connect to a satellite via the solar powered plane ^ the method enables a mobile phone or an IOT device to connect to the solar powered plane ^ the method enables a ship or other vessel to connect to a satellite via the solar powered plane to send AIS / VDES data ^ the method enables a ship or other vessel to connect to the solar powered plane to send AIS / VDES data ^ the method enables a ship or other vessel to connect to the solar powered plane to receive traffic, navigation and safety information data services. ^ the method enables the solar powered planes to provide one or more of: traffic, navigation, PNT (position, navigation and timing) and safety information services to manned and autonomous craft / vehicles. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. Feature Group E: Launch and recovery E.1 Plane with detachable propulsion pod Using an aircraft's own power to climb from the ground to flight altitude is a massive drain on the plane's batteries and can result in the aircraft reaching altitude with depleted batteries, towards the end of the day when no solar power top-up is available. Another problem is that for long duration flight efficiency, the propeller design for a stratospheric plane is optimised for high altitude and so is not ideal for take-off or low altitude flying. In the Solaris system, we can have a separate, detachable pod containing fuel for an ICE engine or an electrical energy source, and a propulsion system, a motor and batteries, where the propulsion system includes at least one propeller optimised for take-off (in contrast to the propeller(s) on the plane, which are optimised for propulsion in the stratosphere). The pod is 47 Attorney Docket No.391529.00003 attached to the plane and is capable of taking the plane to at least mid-altitude (e.g.30,000 feet) on auto-pilot; this is of tremendous value in preserving the battery power in the plane. The pod can be separated from the plane once at altitude and parachuted (or flown with a steerable parachute, parafoil, paraglider or its own wing) back to the launch area. The pod includes an internal battery which is fully charged at take-off, but the pod obtains electrical power for its motor (where an electrical motor is used) during the ascent from batteries in the plane or from the PV cells in the plane, and not its internal battery. The internal battery in the pod can be used to re-charge any batteries in the plane that fall below a threshold charge level. Once the plane is approaching the time that the pod will detach, the pod then starts to re-charge the plane's batteries so that the plane's batteries are fully charged by the time the pod detaches. We can generalise to: A launch system for a solar powered plane configured to operate in the stratosphere, the launch system including a secondary device, comprising a propulsion system with a propeller optimised for take-off and not for stratospheric flight and a secondary battery, in which the secondary device is configured to be attached to the plane and to provide some or all take-off thrust for the plane, and the secondary device draws its power from one or more batteries in the plane and not its secondary battery, but is configured to re-charge one or more batteries in the plane from its secondary battery. Optional features include any one or more of the following: ^ the self-powered device provides some or all thrust for the plane to reach at least 15,000 feet ^ the self-powered device provides some or all thrust for the plane to reach at least 30,000 feet ^ the self-powered device is a fuel (e.g. aviation fuel) powered device ^ the self-powered device is a battery powered device ^ the system is configured to enable the plane to save battery power on take-off ^ the self-powered device is configured to be separated from the plane, for example once the plane has reached a set altitude and to return to land. 48 Attorney Docket No.391529.00003 ^ the self-powered device includes a parachute, such as a steerable parachute / paraglider or wing to enable it to return and land, e.g. in the launch area. ^ the self-powered device includes fuel and a propulsion system or a motor and batteries. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. E.2 Tail-first vertical lift and then nose-down release To deploy a HAPS from a ship or other relatively confined space, a near vertical launch is desirable. This can be reliably achieved by using this process: The Solaris plane is lifted by a balloon or cluster of balloons, tail first, with the fuselage or boom pointing approximately vertically downwards, and the nose facing the ground. At the launch height (e.g. at a stratospheric altitude of between 18,000m to 30,000m), the lift balloons are released, allowing the plane to dive downwards, approximately nose-first. The plane swiftly assumes approximately level flight. Small drogues are currently used to slow descent, but these may be dispensed with pending further development and testing. The path that the plane follows once it is released from the lift balloons depends on the altitude at which it is released. For example, at sea level a 28m wingspan Solaris plane can achieve level flight in a less than 10m vertical drop. By using a balloon lift system, the plane does not need to be designed to be strong and rigid enough to take-off and fly through potentially turbulent air imposing high dynamic wind loadings, before it reaches the calmer, lower density air in the stratosphere; this means that a lighter and simpler airframe can be used, making the Solaris plane both cheaper and more efficient. The plane's propeller blades do not need to be designed to power the plane through a ground level take-off, but can be optimised to work in the far thinner atmosphere of the stratosphere, leading to increased efficiency, greater payloads and extended mission duration. Mechanical gears used to alter the rotational speed of the propeller blades during ascent can be eliminated, saving weight. The 28m wingspan variant of the Solaris plane weighs between 30Kg and 100Kg (excluding payload); payloads can weigh between 15Kg to 100Kg; the cord length is approximately 2.5m; 49 Attorney Docket No.391529.00003 the upper wing surface area to weight ratio is between 0.5 to 2.0 m2 / kg, and preferably from 1.0 to 2.0 m2 / kg. A balloon with 500m3of helium is capable of lifting 50kg at 26,000m altitude; the weight savings described above contribute significantly to the practicability of launching a plane since the total plane and payload weight can be kept to under 200Kg, requiring for example, four 500m3balloons, which is commercially and practically feasible; climb rates of 1 to 10 m / s are possible. We can generalise to: A launch method for a solar powered plane configured to operate in the stratosphere, comprising the step of (a) raising the plane tail first and then (b) releasing the plane at launch altitude so that it initially flies down substantially nose-first, and then attains approximately level flight. Optional features include any one or more of the following: ^ the plane is raised tail first by one or more balloons, tail first, with the fuselage or boom pointing approximately vertically downwards, and the nose facing the ground. ^ at the launch height, the balloons are released allowing the plane to dive downwards, substantially nose-first. ^ the plane drops approximately vertically downwards initially, with its control surfaces set to attain level flight ^ the plane deploys small drogues to slow its initial descent. ^ the plane is released when it has reached its target stratospheric altitude. ^ the plane is released before it has reached its target stratospheric altitude and then ascends under its own power. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. E.3 Plane lands on an autonomous vehicle In the Solaris system, the plane can land on a ground handling vehicle we refer to as an Autonomous Ground Platform (AGP); the AGP moves along the runway at a velocity that 50 Attorney Docket No.391529.00003 matches the Solaris plane that is coming in to land. This effectively reduces the plane’s ground- speed to zero, minimising impact damage, repairs and extending the useful lifetime of the plane, its payload and avionics. Either or both the plane and the AGP can be equipped with short range lidar units (or other kind of imaging unit) for tracking. Lidar units typically weigh less that 100 grams and can hence be mounted on the Solaris plane with minimal weight impact. The preferred variant is however for just the AGP to be equipped with short range lidar units (or other kind of imaging unit). The landing process is as follows: the AGP is positioned on the runway near the runway threshold. The plane is given the location of the AGP as a waypoint. Once within range of the lidars, the AGP drives to match the velocity of the plane, positioning itself to match the plane’s trajectory. The AGP or sensors on the plane instruct the plane to descend the last couple of metres onto the AGP. An alternative is for the AGP to simply detect the height, speed, position and trajectory (and their rates of change) of the plane and not send any instructions at all to the plane; the AGP can include a camera-based imaging unit that is designed to detect a number of markers on the plane, that enable the AGP to lock on to and match the speed, position and trajectory of the plane as it comes in to land safely on the AGP. In this variant, the plane has no need of a LIDAR system or the equipment needed to receive data from the AGP. Once the plane has landed on the AGP, the AGP slows to a stop to allow a visual check by an operator and if necessary, repositioning of the plane on the AGP, before the AGP is commanded or driven by radio control to return to the hangar. The airfield and safe routes are pre-programed into the AGP to avoid it colliding with any airport furniture or structures. This same platform may also be used for assisted take-off. We can generalise to: A method of landing a solar powered plane, such as a plane configured to operate in the stratosphere, on to an Autonomous Ground Platform (AGP); including the step of configuring the AGP to move along a runway at a velocity that matches the plane that is coming in to land, with either the plane and / or the AGP operating an imaging unit that enables, if in the plane, the 51 Attorney Docket No.391529.00003 plane to track the position and motion of the AGP and / or, if in the AGP, for the AGP to track the position and motion of the plane, to ensure that the plane lands safely on the AGP. Optional features include any one or more of the following: ^ the imaging unit, if in the AGP, detects the height, velocity, and position (and / or their rates of change) of the plane ^ the imaging unit, if in the plane, detects the height, velocity, and position (and / or their rates of change) of the AGP. ^ the imaging unit is an active imaging unit that actively illuminates the target plane. ^ the imaging unit is a LIDAR unit or other form of radar, such as SAR or InSAR. ^ the imaging unit is a passive imaging unit that observes the target plane. ^ the imaging unit is a camera in the AGP designed to detect markers on the plane ^ the AGP adapts its position and movements to ensure a safe landing of the plane on the AGP, using the information from the imaging unit in the AGP and / or the plane ^ the AGP or sensors on the plane instruct the plane to descend the last few metres onto the AGP ^ the AGP is commanded or driven by radio control to return to the hangar ^ the airfield and safe routes are pre-programed into the AGP to avoid it colliding with any airport furniture or structures ^ the AGP is also used to launch the plane ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan E.4 Ground handling vehicle that can move in any direction In the Solaris system, the ground handling vehicle, which may be an AGP, as described above or may be manually controlled, is probably in excess of 20m wide and when the plane is on it then the plane's wingspan becomes the effective width at perhaps 34m, although in the front to back dimension its likely to be less than 3m. More generally, the AGP is dimensioned to 52 Attorney Docket No.391529.00003 support a range of HAPS craft sizes, particularly the landing bed / cradle which can be adjusted or swapped out from the underlying vehicle to support different HAPS. The AGP needs to be able to drive in any orientation, from crabbing sideways to get into alignment with the plane as its coming into land then switching smoothly to straight ahead when the plane is landing on it; it then needs to return to the hangar passing wing tip first through gateways and doorways. The AGP vehicle can move in any direction as all 4 of its battery powered wheels can swivel whilst in motion. The platform can be used for assisted take-off (see E.3) as well as a moving platform the Solaris plane lands on, and is capable of traveling at any speed from zero through to faster than the maximum flight speed of the plane. Its swivelling wheels allow it to carry the HAPS sideways (wing-tip first) through narrow hangar doors and runway access gateways, as well as along taxi ways. As noted in E.3 above, for landing, the AGP positions itself at the runway threshold and is able, by being fed real time flight data from the HAPS and / or by using the AGP's own sensors / Lidar to determine the HAPS' exact location, trajectory and speed as it comes in to land. The AGP recovery frame matches the HAPS position in terms of location, speed and trajectory and the HAPS flies to land on, and be safely caught by, the AGP recovery truss, which can then transport the HAPS to a hangar. Figures 22A-C -20 show the ground handling vehicle (AGP) 191 for transporting a Solaris plane 1. The AGP vehicle 191 is designed for various ground operations, such as transportation, maintenance, or any other logical tasks. The AGP 191 includes battery powered swivelling wheels 194 designed to drive in any orientation. The AGP 191 is made up a rectangular chassis section 196, with wheels 194 at each corner and fuselage holders 192 at each corner, sitting over each wheel; AGP 191 includes a lateral spar 195, extending from opposite sides of the rectangular frame, and sized to support the wings of the plane; each spar includes multiple support arms 193 (three are shown) designed to support and hold securely the wings of the plane. The chassis 196 includes 4 such support arms 193. 53 Attorney Docket No.391529.00003 Figure 22A shows the AGP 191 with the plane 1 securely resting on it. Figure 22B shows the AGP 191 on its own, with wheels oriented for forward movement (e.g. parallel to the flight path of a plane coming in to land on the AGP). Figure 22C shows the AGP 191 on its own, with wheels oriented for sideways movement (e.g. when returning to a hanger). Figure 23A is a top-down view of the AGP 191; Figure 23B is a frontal view, showing how the lateral spars 195 are slightly tilted upwards when not supporting a plane; Figure 23C is a side view of the AGP, carrying a plane, and Figure 23D is a side view of the AGP, when not carrying a plane. We can generalise to: A ground handling vehicle for a solar powered plane, the vehicle including (i) a wheeled or tracked chassis, (ii) fuselage holders extending from the chassis and (iii) a pair of lateral spars extending from the chassis, and (iv) a series of support arms mounted on the chassis and lateral spars and configured to support the wings of the plane. And to: A method of landing and storing a solar powered plane, such as a plane configured to operate in the stratosphere, including the steps of a ground handling vehicle (i) driving in one direction to enable the plane to land on the vehicle and, after the plane has landed on the ground handling vehicle (ii) changing its movement in any direction, including perpendicularly. Optional features include any one or more of the following: ^ the ground handling vehicle is, before the plane has landed, configured to change its movement in any direction, including perpendicularly, so that it can align itself with the path of the plane as it comes in to land. ^ the ground handling vehicle is configured, after the plane has landed on and is supported by the ground handling vehicle, to change its movement in any direction, including perpendicularly, so that it can move the plane wingtip first into the hangar. ^ the ground handling vehicle is configured to move off from stationary in any direction. 54 Attorney Docket No.391529.00003 ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. We can also generalise to: A ground handling vehicle for a solar powered plane, the vehicle being a configured to move in any direction. Optional features include any one or more of the following: ^ the ground handling vehicle is electrically powered ^ the ground handling vehicle is capable of autonomous operation, including matching the speed, trajectory and position of a plane coming in to land on the vehicle ^ the ground handling vehicle is configured (i) to drive in a direction that is continuously or rapidly adjusted to enable the vehicle to adjust its position to enable the plane to land on the vehicle and, after the plane has landed on the ground handling vehicle, (ii) to change its movement in any direction, including perpendicularly, to transport the plane to a hangar. ^ the ground handling vehicle is configured to change its trajectory in any direction, including perpendicularly, so that it can align itself with the path of the plane as the plane comes in to land. ^ the ground handling vehicle is configured, after the plane has landed on and is supported by the ground handling vehicle, to change its direction in any direction, including perpendicularly, so that it can move the plane wingtip first into the hangar. ^ the ground handling vehicle is configured to move off from stationary in any direction. ^ the ground handling vehicle includes battery powered wheels that can each swivel through any angle. ^ the ground handling vehicle is configured to support a plane that is a dual fuselage plane with an approximately 32m - 34m wingspan. 55 Attorney Docket No.391529.00003 Feature Group F: Use cases F.1 Improved training of AI based models For many applications, such as weather monitoring, earth observation, earth imaging, border security, maritime patrols, anti-piracy operations, disaster response and agricultural observation, low earth orbit (LEO) satellites are currently used. But a typical LEO satellite with an orbital period of 120 minutes and a velocity of 27,000 Km / h might only be over the same area of the planet for a fraction of a second each day. Another approach is to use light aircraft, but these are both costly and cannot loiter over a target area for more than a few hours. A Solaris plane can loiter directly over a target area for many weeks, providing continuous, real-time data throughout this time. In a 24 hr period, a Solaris sensor at say 9Hz refresh is gathering circa 777,000 images / samples of the target scene. A satellite constellation at full capacity may gather 50-100: a single Solaris plane can deliver up to 15,000x more information, giving a significant boost in temporal resolution, at a far lower cost. For AI and signal processing, this larger data set (sample set) enables larger integration times which enable an exponential gain in resolution (signal to noise) such that objects, movements and changes can be seen at far higher resolutions and with much higher certainty than from a few samples. Further, the fact that Solaris planes hold-station by circling over the spot adds a 360º dimension to the data sets, further boosting resolution and reliable object, movement or event detection. The combined effect is a significant gain in spatial-temporal resolutions for any sensor / instrument flown, which closes critical observation gaps across a wide range of Earth Observation missions. Solaris planes can hence persistently monitor earth areas and generate continuous real-time data over many weeks; a key advantage over satellite based systems. Satellite systems are also limited to the imaging and earth monitoring systems available when the satellite is designed; these can be obsolete after a few years, but cannot be replaced; the imaging and earth 56 Attorney Docket No.391529.00003 monitoring systems payload in a Solaris plane can be updated prior to a mission and so the most up to date and lightweight systems can be used. Solaris planes use high-capacity satcom networks to live stream their data to a satellite and for that satellite to then transmit that data to a ground station for immediate analysis and use. Solaris planes may also use a free-space optical link for transmitting directly to a ground station, another Solaris plane, or a satellite. One or more sensors or imaging subsystems that are configured to operate in the stratosphere may be used in the Solaris plane and the outputs of each sensor or imaging subsystem combined (locally in a plane, or in data-connected planes, or on-the ground or remotely) to detect, predict or monitor a wide range of natural disasters or events. We can generalise to: A method of generating training data for training an AI based system comprising the steps of: (i) operating a solar powered plane, such as a plane configured to operate in the stratosphere, to (a) capture data for a region over a continuous period that is at least 10 times longer than the continuous period for which a light aircraft could capture data for that region and to (b) capture a quantity of data for that region that is at least 10 times greater than the quantity of data that a constellation of low earth orbit satellites could capture over the same continuous period. F.2 Improved inference for AI based models Because Solaris suborbital platforms provide continuous, real-time data feeds that last for hours, days or even weeks for a specific target area, raw and processed (as in the above examples), this data can then be used to significantly improve AI based predictive models, such as those used in disaster or emergency response environments. For example, being able to predict winds, movement of fires, water flows, rain etc. is key to incident room decision making. The problem is that most of these models are using relatively old data, perhaps satellite imagery from several hours ago, or field reports from a very small sample of events in the field. So, their decision making is not based on continuous, real-time data (inputs and 57 Attorney Docket No.391529.00003 outputs then generated from their predictive systems), nor data for a specific target area that has been captured over days or even weeks of persistent, continuous data capture. However, Solaris changes this dramatically by live feeding in new, dynamic, volumetric data of events and how they are varying in time, over continuous and extended time periods (e.g. hours, or days or even weeks) to greatly improve the accuracy and value of predictive models / systems. This new data that is fed to an AI system to enable the AI system to make inferences or predictions is called inference data. With live feeding of Solaris data to these predictive systems, we can accelerate these models up to near real-time (the time between data capture, streaming to the ground and ingesting and processing by the predictive system - a minute or two), which will naturally boost incident room accuracy and quality of decision making, closing a critical observation gap for predictive modelling. Further, the output from the predictive systems can be fed-back into Solaris’ own mission and data gathering systems, along with incident room instructions, in a feedback loop that can be used by a machine learning system to improve the accuracy and value of Solaris’ operations and services for customers. Solaris can vary its mission including where to fly, rate of coverage, which sensors to use, what sensor settings to apply etc., to optimize the total system performance. Solaris planes can become the co-ordination point by providing both live ‘eyes-on’ data for controllers and first-responders, but also providing navigation, mission and other data to people and vehicles (manned or autonomous) during the response stages. Solaris planes can carry a range of equipment, communications and even its own navigation services (INSS / GNSS) to ensure highly precise operations below. This improves accuracy, reliability, safety and reduces costs. One example is in fire-fighting where Solaris planes can detect fires over wide areas and then guide in drones / UAVs or even ground vehicles to remote locations to deliver fire-suppressants. Solaris can monitor the effect of suppressants or other tactics to ensure that they have worked, to either guide another craft to continue, or the original one to return. It can enable co- 58 Attorney Docket No.391529.00003 ordination of actions in real-time, and measure the effectiveness in real-time of these actions; it can guide craft and people to / from where needed, safely, and efficiently; it can optimise the overall effectiveness and cost of fighting fires. Another is in search and rescue where Solaris planes can detect a vessel or person(s) in distress and direct lifeboats, drones or autonomous craft to where they are needed. Figure 24 illustrates a schematic diagram showing data flow within one embodiment of the present invention. In one embodiment, live data from the glider 1 is taken in and processed by the system of the present invention and processed either on the glider 1 itself, or on a separate, remote processor. The workflow starts at the data ingestion stage 200, involving mission planning, including generating pre-tagged meta-data (e.g. such as known areas of high interest, seeing long range weather data that will impact the direction of a disaster and our mission, ground layer / drone layer data providing high resolution samples of the larger target area and GIS referencing, so that we can reliably resolve the location of data coming from different sources using the GIS geolocation standard, and likewise produce our processed data to the same standards for onward compatibility. Live data is received at stage 201 from the Solaris planes; this data may in stage 201 be subject to anonymisation and also augmentation with other data sources - e.g. adding a layer of known risks, objects, features that improve the detection and classification of scene features and adaptation - e.g. ortho-rectification, filtering, enhancing, transposing data as required for improving the context of what’s being observed (that may affect onward processing) and enhancing the capability of onward stages. The data then is sent to processing stage 202, which includes AI / ML based processing (object identification, event detection, signal processing), generating derived data sets. Processing stage 202 is connected, via APIs 205 to various specialist processing modules, such as machine learning module 201, specialist data processing module 209, signal processing module 208. The derived data sets are in product delivery stage 203 processed for object / event selection, formatting and GIS referencing. Data is output to decisioning stage 204; this data can be in various formats, such as raw, point cloud data, or web-based data for immediate viewing, or event data for injection into a process or workflow. Decisioning stage 204 is typically human 59 Attorney Docket No.391529.00003 assisted; in the disaster response scenario, instructions will be sent to various field operatives (e.g. search teams, helicopters, drones etc.). Decisioning stage 204 can send mission parameter and processing priority updates 207 as a feedback loop to any and indeed all of the earlier stages. One especially important aspect of the feedback loop is the ability to update the prediction models 212 that model and predict how real-world events will unfold and how different interventions (driven by the decisioning stage 204) affect that unfolding. For example, the system may be monitoring a wildfire; the prediction model 212 may model how fires spread based on various factors, such as meteorology, topology, vegetation, soil moisture, hydrology, man-made structures, and how that spread can be controlled by fire-breaks, backfiring, water and foam; because Solaris planes can provide real-time, continuous and persistent (lasting days or weeks) data tracking fires (e.g. using infra-red video feeds and SAR data) and automatically identifying firebreaks and the location of fire crew and their equipment, enabling the prediction model to be provided with the richest and most up to date data; that in turn enables not only the prediction model itself to generate the most accurate intervention recommendations, but for the prediction model itself to be altered, adjusted and improved in the light of the feedback data. Data sets of actual events in high spatial-temporal resolution can be used to adapt and train predictive models to higher levels of accuracy and reliability; this again closes critical observation gaps for reliable modelling for predictive sciences. We can generalise to: A method of generating inference data for an AI based system comprising the steps of: (i) operating a solar powered plane, such as a plane configured to operate in the stratosphere, to (a) capture data for a region over a continuous period that is at least 10 times longer than the continuous period for which a light aircraft could capture data for that region and to (b) capture a quantity of data for that region that is at least 10 times greater than the quantity of data that a constellation of low earth orbit satellites could capture over the same continuous period. In one embodiment, the processing involves one or more application programming interfaces (APIs), including, but not limited to, at least one machine learning module, at least one 60 Attorney Docket No.391529.00003 specialist data processing module (i.e., specific data processing tools adapted for specific tasks), and / or signal processing modules. In one embodiment, the system is able to receive a selection of at least one external API to use by at least one user device, such that customers are able to select their own software models for specific data processing tasks. The system is operable to utilize a plurality of learning techniques including, but not limited to, machine learning (ML), artificial intelligence (AI), deep learning (DL), neural networks (NNs), artificial neural networks (ANNs), Convolutional Neural Networks (CNNs), support vector machines (SVMs), Markov decision process (MDP), and / or natural language processing (NLP). The system is operable to use any of the aforementioned learning techniques alone or in combination. Further, the system is operable to utilize predictive analytics techniques including, but not limited to, machine learning (ML), artificial intelligence (AI), neural networks (NNs) (e.g., long short-term memory (LSTM) neural networks), deep learning, historical data, and / or data mining to make future predictions and / or models. The system is preferably operable to recommend and / or perform actions based on historical data, external data sources, ML, AI, NNs, and / or other learning techniques. The system is operable to utilize predictive modeling and / or optimization algorithms including, but not limited to, heuristic algorithms, particle swarm optimization, genetic algorithms, technical analysis descriptors, combinatorial algorithms, quantum optimization algorithms, iterative methods, deep learning techniques, and / or feature selection techniques. Figure 25 is a schematic diagram of an embodiment of the invention illustrating a computer system, generally described as 800, having a network 810, a plurality of computing devices 820, 830, 840, a server 850, and a database 870. The server 850 is constructed, configured, and coupled to enable communication over a network 810 with a plurality of computing devices 820, 830, 840. The server 850 includes a processing unit 851 with an operating system 852. The operating system 852 enables the server 850 to communicate through network 810 with the remote, distributed user devices. Database 870 is operable to house an operating system 872, memory 874, and programs 876. 61 Attorney Docket No.391529.00003 In one embodiment of the invention, the system 800 includes a network 810 for distributed communication via a wireless communication antenna 812 and processing by at least one mobile communication computing device 830. Alternatively, wireless and wired communication and connectivity between devices and components described herein include wireless network communication such as WI-FI, WORLDWIDE INTEROPERABILITY FOR MICROWAVE ACCESS (WIMAX), Radio Frequency (RF) communication including RF identification (RFID), NEAR FIELD COMMUNICATION (NFC), BLUETOOTH including BLUETOOTH LOW ENERGY (BLE), ZIGBEE, Infrared (IR) communication, cellular communication, satellite communication, Universal Serial Bus (USB), Ethernet communications, communication via fiber-optic cables, coaxial cables, twisted pair cables, and / or any other type of wireless or wired communication. In another embodiment of the invention, the system 800 is a virtualized computing system capable of executing any or all aspects of software and / or application components presented herein on the computing devices 820, 830, 840. In certain aspects, the computer system 800 is operable to be implemented using hardware or a combination of software and hardware, either in a dedicated computing device, or integrated into another entity, or distributed across multiple entities or computing devices. By way of example, and not limitation, the computing devices 820, 830, 840 are intended to represent various forms of electronic devices including at least a processor and a memory, such as a server, blade server, mainframe, mobile phone, personal digital assistant (PDA), smartphone, desktop computer, netbook computer, tablet computer, workstation, laptop, and other similar computing devices. The components shown here, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of the invention described and / or claimed in the present application. In one embodiment, the computing device 820 includes components such as a processor 860, a system memory 862 having a random access memory (RAM) 864 and a read-only memory (ROM) 866, and a system bus 868 that couples the memory 862 to the processor 860. In another embodiment, the computing device 830 is operable to additionally include components such as a storage device 890 for storing the operating system 892 and one or more application programs 894, a network interface unit 896, and / or an input / output controller 898. Each of the components is operable to be coupled to each other through at least one bus 868. The input / output controller 898 is operable to receive and process input from, or provide output to, 62 Attorney Docket No.391529.00003 a number of other devices 899, including, but not limited to, alphanumeric input devices, mice, electronic styluses, display units, touch screens, gaming controllers, joy sticks, touch pads, signal generation devices (e.g., speakers), augmented reality / virtual reality (AR / VR) devices (e.g., AR / VR headsets), or printers. By way of example, and not limitation, the processor 860 is operable to be a general-purpose microprocessor (e.g., a central processing unit (CPU)), a graphics processing unit (GPU), a microcontroller, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Programmable Logic Device (PLD), a controller, a state machine, gated or transistor logic, discrete hardware components, or any other suitable entity or combinations thereof that can perform calculations, process instructions for execution, and / or other manipulations of information. In another implementation, shown as 840 in Figure 25, multiple processors 860 and / or multiple buses 868 are operable to be used, as appropriate, along with multiple memories 862 of multiple types (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core). Also, multiple computing devices are operable to be connected, with each device providing portions of the necessary operations (e.g., a server bank, a group of blade servers, or a multi- processor system). Alternatively, some steps or methods are operable to be performed by circuitry that is specific to a given function. According to various embodiments, the computer system 800 is operable to operate in a networked environment using logical connections to local and / or remote computing devices 820, 830, 840 through a network 810. A computing device 830 is operable to connect to a network 810 through a network interface unit 896 connected to a bus 868. Computing devices are operable to communicate communication media through wired networks, direct-wired connections or wirelessly, such as acoustic, RF, or infrared, through an antenna 897 in communication with the network antenna 812 and the network interface unit 896, which are operable to include digital signal processing circuitry when necessary. The network interface unit 896 is operable to provide for communications under various modes or protocols. 63 Attorney Docket No.391529.00003 In one or more exemplary aspects, the instructions are operable to be implemented in hardware, software, firmware, or any combinations thereof. A computer readable medium is operable to provide volatile or non-volatile storage for one or more sets of instructions, such as operating systems, data structures, program modules, applications, or other data embodying any one or more of the methodologies or functions described herein. The computer readable medium is operable to include the memory 862, the processor 860, and / or the storage media 890 and is operable be a single medium or multiple media (e.g., a centralized or distributed computer system) that store the one or more sets of instructions 900. Non-transitory computer readable media includes all computer readable media, with the sole exception being a transitory, propagating signal per se. The instructions 900 are further operable to be transmitted or received over the network 810 via the network interface unit 896 as communication media, which is operable to include a modulated data signal such as a carrier wave or other transport mechanism and includes any delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics changed or set in a manner as to encode information in the signal. Storage devices 890 and memory 862 include, but are not limited to, volatile and non-volatile media such as cache, RAM, ROM, EPROM, EEPROM, FLASH memory, or other solid state memory technology; discs (e.g., digital versatile discs (DVD), HD-DVD, BLU-RAY, compact disc (CD), or CD-ROM) or other optical storage; magnetic cassettes, magnetic tape, magnetic disk storage, floppy disks, or other magnetic storage devices; or any other medium that can be used to store the computer readable instructions and which can be accessed by the computer system 800. In one embodiment, the computer system 800 is within a cloud-based network. In one embodiment, the server 850 is a designated physical server for distributed computing devices 820, 830, and 840. In one embodiment, the server 850 is a cloud-based server platform. In one embodiment, the cloud-based server platform hosts serverless functions for distributed computing devices 820, 830, and 840. In another embodiment, the computer system 800 is within an edge computing network. The server 850 is an edge server, and the database 870 is an edge database. The edge server 850 and the edge database 870 are part of an edge computing platform. In one embodiment, the 64 Attorney Docket No.391529.00003 edge server 850 and the edge database 870 are designated to distributed computing devices 820, 830, and 840. In one embodiment, the edge server 850 and the edge database 870 are not designated for distributed computing devices 820, 830, and 840. The distributed computing devices 820, 830, and 840 connect to an edge server in the edge computing network based on proximity, availability, latency, bandwidth, and / or other factors. It is also contemplated that the computer system 800 is operable to not include all of the components shown in Figure 25 is operable to include other components that are not explicitly shown in Figure 25 or is operable to utilize an architecture completely different than that shown in Figure 25. F.3 Combining multiple sensors or imaging subsystems Imaging subsystems providing real-time 3D data, such as SAR or LiDAR or any other 3D imaging subsystems, may be combined with thermal / hyperspectral / wideband and other imagers in order to provide a live 3D render of what is actually happening in an area of interest; the various subsystems and imagers may all be in a single Solaris plane, or distributed across several Solaris planes, and other types of platforms. Hence the 3D data measured by the 3D imaging subsystems may be enhanced using a multitude of sensor types, such as 2D thermal imaging or hyperspectral scanning sensors. The classification of objects and events being detected by SAR / LiDAR or other subsystems can therefore be improved. For example, 2D thermal imaging sensors may be used to provide several measurements, such as temperature measurements or differences, heat signature or pattern. Hyperspectral imaging sensors may be used to detect the chemistry / material type being observed (e.g. vegetation type, soil, water, etc). A Synthetic Aperture Radar (SAR / InSAR) subsystem can be used to capture high-resolution 3D images for high-resolution mapping, underground structure detection, disaster monitoring or environmental surveys. This is done by transmitting radar signals and analysing the backscattered signals in real-time or near real-time. The SAR subsystem parameters, such as operating frequency, antenna size, etc., can be tuned for suborbital measurements depending 65 Attorney Docket No.391529.00003 on the intended application. The SAR subsystem used may be configured to provide suborbital measurement data in real-time with high resolution capabilities. The resolution can also be adjusted during a mission, such as to provide 1-2m resolution for a wide area and then to focus on smaller area at 1-2cm resolution. For example, the SAR subsystem can be used to detect vegetation canopies and to detect or identify the vegetation types and to assess the vegetation moisture content or hydrological properties. A thermal imaging subsystem may also be used for temperature mapping of an area. One limitation is that thermal imagers only render in 2D, since they use a 2D sensor array, with each sensor in the array outputting the magnitude of the detected thermal signal. This is similar for other energy based passive sensors such as hyperspectral and wideband imaging sensors. A 2D thermal imaging (or any other type of wide-band imaging (e.g. hyper spectral)) subsystem may be combined with SAR or LiDAR subsystems or any other 3D imaging subsystems to provide 3D data in real time for a wide number of, e.g. natural disaster or event monitoring, such as fire detection. As an example, in a fire, thermal dots must be overlaid onto a terrain map, and both measurements need to align (GIS, ortho-rectification and other methods used to estimate where you are looking are all prone to errors than can compound up). However, the terrain map that is available may not always be current. The density of vegetation may be different, objects / people / assets may be in different places, etc. By combining 2D thermal imaging with SAR / LiDAR-based imaging, the advantage is that SAR provides 3D objects data to a very high accuracy, unlike optical or other imaging systems. Further, SAR is good at seeing through cloud, smoke, and other atmospheric clutter. By combining both 2D thermal imaging and 3D SAR - we can create a 3D thermal image of what is burning - the shape / volume of the object, the rate of change, etc, providing an improvement in managing fires (wildfires in particular) and prioritizing (triaging) what the next best action may be. All these lead to highly accurate and highly automated triaging of events to make decision making as effective and accurate as possible. 66 Attorney Docket No.391529.00003 The SAR and thermal imaging subsystem may be on board a Solaris suborbital platform, or may be flying in a constellation where larger apertures and accuracy over wider areas can be obtained, or a combination of both. The SAR subsystems can determine their separation down to sub-millimeter levels (or even micron levels) and their geo-location to similar accuracy. And all of this new data, when fed into AI or ML predictive models, improves their accuracy and value - both because there is new data (dynamic 3D / volumetric and object / type) and because it’s now real-time and persistent. Additionally other sensors such as imaging sensor data, or non-imaging sensor data may also be used to enhance the measured data. Further, with SAR / LiDAR, we can also provide the incident controller a real-time picture of what’s in their space of operation - ground and aerial - to increase situational awareness, simplify data gathering (reduce planes / helicopter / drones) in theatre and focus on monitoring progress of action on the ground. As an example, being able to see the firefighting craft (planes, helicopters, drones, ground vehicles, people) in real-time in one image / screen (video) and not have to rely on patching in small bits of data from different systems (e.g. from a plane, satellite, drone, radio reports, civilians, social media, which are all patchy, not in time sequence and can trigger many false positives, etc…) is a tremendous practical advantage. Now the incident room can use the above live capability to triage events and use the live data to plan things like approach vectors for dropping fire retardant given ground conditions, flames, wind, rate of progress, location of important objects / people / assets / nature. And being able to see the effectiveness of fire retardant being dropped on a particular location and watching that space for hours / days after improves the efficacy of operations. Often retardant does not hit the mark, hits it but not fully, hits it fully, but the fire re-emerges, smoulders quietly for hours before wind or other re-ignites it, burns underground, and emerges some distance away and starts a new fire. This data can now be added into the operators' systems for complete triaging and optimal response to events in the field. With Solaris’ persistent coverage using combinations of sensors, we can provide that persistent situational awareness that is essential for natural disaster mitigation and control. To re-cap, Solaris can take sensor data (often 2D, such as thermal, wind, hydrology, vegetation, mineralogy / chemistry) and overlay it on 3D data sets which enhances its usefulness, 67 Attorney Docket No.391529.00003 particularly when both are sourced live so that the full context is available from one set into the other (e.g. during disasters when you need to see both the context and a specific measurement of say fire, wind, water, etc). We can generalise as follows: A solar powered plane, such as a plane configured to operate in the stratosphere and configured to enable the detection or monitoring of a natural disaster event by measuring real-time data associated with a region of interest, in which the plane includes a 3D imaging subsystem and a 2D imaging unit. A computer implemented method of detecting or monitoring of a natural disaster event, in which a solar powered plane is operating in the stratosphere and includes a 3D imaging subsystem and a 2D imaging unit that enables measuring real-time 3D data associated with a region of interest. Optional features include any one or more of the following: ^ 3D imaging subsystem includes a 3D imaging unit, such as SAR, inSar or LidAR. ^ 3D data includes 3D objects data of the region of interest, in which the object is one of the following: tree, bush, grass, building, vehicle people, animal etc. ^ 2D imaging unit includes thermal, hyperspectral or wideband sensors. ^ a data fusion subsystem is configured to fuse or combine the data provided by the 3D imaging unit and the 2D imaging unit. ^ Measured data takes into account environmental conditions. ^ the 3D Imaging subsystem together with the 2D imaging unit determines the movement of objects in an area of interest. ^ the 3D Imaging subsystem together with the 2D imaging unit identifies risk or danger, such as fire, collapse risk, flooding event or any other potential danger. ^ the 3D Imaging subsystem together with the 2D imaging unit is mounted on the solar powered plane. ^ the 3D Imaging subsystems together with the 2D imaging units are mounted on a constellation of solar powered planes and operate as a distributed system. 68 Attorney Docket No.391529.00003 ^ the 3D Imaging subsystem together with the 2D imaging unit is configured to have parameters that are tuneable during flight, such as to vary the resolution capabilities. ^ the output of the 3D imaging subsystem together with the 2D imaging unit is fed into a machine learning or AI based subsystem as training data. ^ the output of the 3D imaging subsystem together with the 2D imaging unit is fed into a machine learning or AI based subsystem as inference data. ^ the output of the 3D imaging subsystem together with the 2D imaging unit is fed into a machine learning or AI based subsystem that is configured to classify objects based on a specific natural disaster event. ^ the output of the 3D imaging subsystem together with the 2D imaging unit is fed into a machine learning or AI based subsystem that is configured to predict natural disaster event. ^ the output of the 3D imaging subsystem together with the 2D imaging unit is fed into a workflow automation subsystem such as a triaging subsystem that is configured to automatically triage a sequence of rescue actions based on the natural disaster detected. ^ the rescue actions includes guidance of drones, UAVs or other rescue vehicles to remote locations for specific task. ^ the 3D imaging Subsystem is configured to monitor the effect of rescue actions or other tactics in real time. ^ the 3D imaging subsystem together with the 2D imaging unit detects moisture levels or hydrological properties and estimates change in moisture levels or hydrological properties. ^ The plane is configured to transmit an alarm when a risk is identified, such as if the moisture levels or hydrological properties exceed pre-defined thresholds. ^ the natural disaster event is a fire, and the 3D imaging subsystem and / or 2D imaging unit is configured to monitor ground conditions, flames, wind, rate of progress, location of important objects / people / assets / nature. ^ the 3D imaging subsystem together with the 2D imaging unit measures or estimates volume of fuel stock based on one or more of the following: type of fuel being burned or about to be burned, rate of change, such as rate at which fuel is being burned, or fuel consumption. ^ the 3D imaging subsystem together with the 2D imaging unit are configured to monitor effectiveness of fire retardant or suppressant in real time. ^ the 3D imaging subsystem together with the imaging unit estimates indicator of underground fire. 69 Attorney Docket No.391529.00003 ^ the 3D imaging subsystem together with the 2D imaging unit estimates indicator of subsidence, or collapse, such as sudden ground depression. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. F.4 Dark vessel monitoring The Solaris plane (or a constellation of Solaris planes) spots and tracks sea-going vessels using an imaging system (e.g. synthetic aperture radar) for detecting sea-going vessels; it includes a receiver for automatic identification system (AIS or S-AIS or the newer VDES) signals. Vessels that are tracked by the plane but are not sending AIS or S-AIS (or VDES) signal can be identified (either on the plane or on the ground) as potential dark vessels. The plane can also act as a relay for AIS, S-AIS or VDES signals, sharing them with other Solaris planes and also transmit to other planes and to the ground data that enables the identification of dark vessels. A constellation of these planes could provide persistent imaging of areas where dark vessels are likely to be present or have been identified. Solaris planes can also carry an RF detection sensor to detect any RF signals to identify craft - e.g. their mobile phones, or other radio equipment they’re using. Also, detecting odd patterns of movement would be an indicator that a vessel is say dumping, collecting, or performing an illicit act. AI would enhance identification and profiling of such vessel / craft or plane (e.g. turned off its ADS-B or similar identification transponder) We can generalise to: A solar powered plane configured to operate in the stratosphere and configured to enable the detection of dark sea-going vessels by including (i) an imaging system (e.g. synthetic aperture radar) for detecting and tracking sea vessels; and (ii) a receiver for automatic identification system (AIS, S-AIS or VDES) signals; and in which the plane is configured to process or send data from the imaging system and the receiver to enable vessels that are tracked by the plane but are not sending AIS, S-AIS or VDES signal to be identified as potential dark vessels. Optional features include any one or more of the following: 70 Attorney Docket No.391529.00003 ^ vessels that are tracked by the plane but are not sending AIS, S-AIS or VDES signal are identified locally on the plane as dark vessels. ^ vessels that are tracked by the plane but are not sending AIS, S-AIS or VDES signal are identified on the ground as dark vessels. ^ the plane is further configured to act as a relay for the AIS, S-AIS or VDES signals and / or data that enables the identification of dark vessels ^ the plane is further configured to transmit to ground data that enables the identification of dark vessels. ^ the plane is further configured with an RF detection sensor to detect RF signals from the sea-going vessels. ^ the plane is further configured to collect vessel movement data to enable patterns of movement to be detected that are associated with dumping, collecting, or performing an illicit act. ^ a constellation of planes provides persistent imaging of areas where dark vessels are likely to be present or have been identified. ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. F.5 Spy balloon capture High altitude balloons (such as alleged spy balloons) have proven notoriously difficult to “Shoot Down”; this is because the balloon is travelling at the speed of the wind, likely less that 70 kts but at high altitude conventional aircraft have to fly at several hundred Kts to avoid stalling. However, the Solaris plane at high altitude can fly at less than 50kts if required, and this allows the plane to be manoeuvred to smoothly intercept or fly directly above the target balloon. The Solaris plane can be set on a path to intercept an errant balloon, such as a potential spy balloon; the plane releases a net or tether that attaches to the balloon or its payload cables and puts the balloon out of equilibrium thus causing the balloon to gently descend. Alternatively the plane could drop a small hot wire mesh and batteries onto the balloon; once activated, the 71 Attorney Docket No.391529.00003 hot wire would melt through the balloon fabric causing it to deflate. The battery pack could be fitted with a small parachute to at least control the descent of the batteries. Alternatively, the Solaris plane can include a ‘Y’ shaped capture prong on the front (or similar) that enables the plane to fly into say the flight train or payload cables, attach to it and so add to the mass of the plane to the balloon payload to bring the entire payload and balloon down intact, or to drag it down to several hundred feet off the ground, where it can be released and recovered. This may include the use of the Solaris plane’s propulsion and flight control surfaces to actively drive and steer the balloon to a target area or landing site, rather than drift with the winds and land in undesirable areas. We can generalise to: A solar powered plane configured to operate in the stratosphere and including a system designed to be released from the plane to disable a balloon. Optional features include any one or more of the following: ^ the system released from the plane is a net or tether configured to attach to the balloon or its payload cables to put the balloon out of equilibrium, thus causing the balloon and its payload to descend to ground. ^ the system released from the plane is hot wire mesh and batteries configured to melt through the balloon fabric, causing it to deflate. ^ the system released from the plane is a ‘Y’ shaped capture prong that enables the plane to fly into say the flight train or payload cables, attach to it and so add to the mass of the plane to the balloon payload to bring the entire payload and balloon down ^ the plane is a dual fuselage plane with an approximately 32m - 34m wingspan. F.6 Non-GPS location system The Solaris plane can include a stellar navigation system as described in WO 2017 / 158326 (the contents of which are incorporated by reference) to determine its position with cm or sub-cm 72 Attorney Docket No.391529.00003 accuracy; in addition, each plane includes an atomic clock or a system that can receive and use time signals derived from an atomic clock. The plane transmits its position data and time signal data; when there is a constellation of these planes, then a user (e.g. on the ground, at sea or in the air) can infer their location using these position and time signals, much like the current GPS or other GNSS systems, but without the recourse to these GPS or other GNSS systems. We can generalise to: A constellation of solar powered planes, each configured to operate in the stratosphere and configured to detect their position with reference to a star map, and to transmit that position data with time signal data to enable a user to infer their location using these position and time signals, without the recourse to the GPS or other GNSS systems. Optional features include any one or more of the following: ^ each plane includes a system that can receive and use time signals derived from an atomic clock ^ each plane includes an atomic clock. ^ each plane is a dual fuselage plane with an approximately 32m - 34m wingspan. F.7 Weather / Wind data capture process For many years balloonists and others have released small helium or hydrogen balloons to give either a visual indication (or if fitted with a data capture device generally referred to as a sonde or radiosonde, then actual digital data) of the wind direction and speed at different heights as the balloon ascends. Eventually these balloons burst: it is also known to track the radiosonde descent after balloon burst. With balloon bursts, the remnants descend, causing “plastic” pollution with the potential to damage animals and fish if ingested. Consequently, the Australian government has banded the release of these sorts of balloons. In the Solaris system, we can use (i) a tracker sonde, or (ii) sand (perhaps 100g to 300g); each is mounted in a paper cup (we will refer to either as 'ballast)'; the cup has a very small paper parachute with cotton rather than man made threads to attach the cup to the parachute, so there is much reduced environmental damage compared to synthetic balloons. 73 Attorney Docket No.391529.00003 Either of these entire assemblies can be wrapped up and secured to a small drone, or a small UAV, e.g. a powered model aircraft, in such a way that they can be released at altitude. The drone can then be flown to altitude, were the parachute and ballast (either a tracker sonde or just sand) is then released. If the ballast is of sand, then wind direction is only determined by visual sightings of the relative movement of the parachute during descent. If the parachute has a sonde attached, then digital data can be captured on the ground using a receiver attached to a computer. Some sondes have a ground finding system that allows them to be collected after use and reused many times. The paper parachute may also be reused. The approach is to capture the weather / wind data (e.g. wind velocity, temperature, humidity - any other variables that can affect the flight of the Solaris plane) solely during a descent rather than an ascent, and without using a balloon but instead a drone or UAV. This has several other advantages, one of which is that the drone can be flown upwind from the observer / receiver on the ground, unlike a balloon. This reduces the chance of the sonde being blown out of range down-wind of the observer, who in the conventional balloon scenario would be at the point of release from the ground. Another advantage is that when using a balloon, it often travels many tens of miles down wind after it has gone out of sight and is no longer useful. We can generalise to: A weather data capture method including the steps of (i) using a drone or UAV to fly a device to altitude; (ii) releasing the device at altitude and (iii) monitoring the descent of the device to generate weather data. Optional features include any one or more of the following: ^ weather data includes wind data ^ the device descends under a parachute ^ the parachute is a paper parachute attached by cotton threads to the device ^ the device includes a tracker sonde ^ the device includes a weight, such as sand, and the wind direction is determined by visual sightings of the relative movement of the device and its parachute during descent 74 Attorney Docket No.391529.00003 Miscellaneous Use Cases F.8 Urban Eyes Solaris planes are uniquely placed to source live, video-grade data over significant areas of our planet. One class of high-value area is urban. Solaris planes can provide 24 / 7 live visibility of all urban spaces using cameras, IR and even SAR / InSAR (synthetic aperture radar) enabling it to identify the location and movement of vehicles, assets, people, plants, vegetation, animals and also monitor events, infrastructure and even the progress of natural events such as weather, water, dust, pollutants, fires, floods, earthquakes, infestations / migration, etc. A true, multi- dimensional living map and extremely rich data detailing the complex patterns of life and at scale can be generated. Solaris planes can enable a wide range of municipal services to a broad set of stakeholders with the benefit that each reduces friction, improves efficiency and enables better use of busy, contested urban spaces along with improving safety, security and optimization of critical assets and infrastructure. Solaris can provide a real-world picture of actual events and has no reliance of individual assets or spaces being ‘wired-up’ and registered to a central system (e.g. current traffic mapping systems rely on devices being connected and sharing their location data) meaning all non-GPS, non-connected devices, vehicles, people, animals are by default included. In the race to build a digital (virtual) system, Solaris provides the real-world data for a true ‘digital twin’ capability. This Solaris urban data layer is a rich enabler of many civic, commercial and agency services that go beyond some of the examples listed here. F.9 Parking An example use case of this is finding real-time parking spots. For instance, a user could simply sign up to the Solaris ‘Find-A-Park’ service which would in real-time know where parking spots were. You would simply put in your destination and select ‘Find-A-Park’ and it 75 Attorney Docket No.391529.00003 would provide your route to available spots and in real-time update your routing as options change. It might even pre-reserve a spot for you if those slots were allocated / managed on this system or via a third party system. Further, private parking spots, driveways and other private parking assets could also be listed and booked and paid for through this service. Finding an available EV charging station is another variant of this. There are many benefits to users (less stress, more effective routing), traffic (fewer cars blocking up roads roaming around, waiting as they hunt for spots), owners (more effective way to manage and monetize parking spots). For covered indoor / underground parks, by knowing the capacity and monitoring the numbers in / out, Solaris planes would be able to calculate the availability of parking in each. Naturally the car park could also share both capacity and actual parking slots available to control their own flows and business. And of course municipalities would benefit from being able to better plan urban usage, traffic flows, safety, enforcement and a range of civic services. Parking control and enforcement can be highly automated by having real time facts starting with directing agents to where vehicles are currently illegally parked through to ultimately automating enforcement and issuance of penalties F.10 Traffic / movements Solaris planes can persistently image traffic in real-time across a broad urban area - not just traffic on main arteries or where there are traffic cameras / sensors; so Solaris enables a complete capability in live traffic management, incident management, safety, security and control essential for urban-wide (system-wide) optimization, including the following: o Traffic flows – precise volumes, speeds, down to each individual vehicle o Real time incidents – jams, crashes, holes, pipe bursts, fires, lights out o Geo-fencing borders for land, sea and air, including geo-fencing specific areas either persistently or on a timed basis o Security – live incidents, track vehicles, movements, etc… o No need for helicopters / planes for tracking / chasing rogue vehicles or people or animals, etc. 76 Attorney Docket No.391529.00003 o The video streams would allow for seeing the full path of a vehicle into and out of a scene to establish full facts rather than rely on incomplete facts / local cameras / sensors. o i.e. – you could see who / what caused an event, know their origin and even follow them to their final location This also applies for a wide range of urban needs – e.g. rubbish / trash / refuse locations, collection, status, abuses etc., including seeing illegal dumping / tipping or other forms of abandonment and being able to track provenance and where the responsibly party then went. It could also be used to calculate the volumes and flows of people, such as at events, in / out of public areas, retail properties, offices / towers, buildings and transport systems, during a crisis or disaster. Again, this is valuable data for planning, management, safety / security and assisting agents and first responders with actual live data to more accurately and efficiently manage a range of events. Solaris planes can be used for AIS / VDES detection / relaying of ships, as noted earlier. Solaris planes can also apply these detection / relaying techniques to autonomous vehicles (cars, trucks, farm vehicles, drones, robots, etc.) that will be required to use a form of self-identification, as well as sense and avoidance, in their traffic management systems, as well as future traffic management systems that co-ordinate the movement of vehicles. Vehicles may go dark, they may lose network connectivity or be out of range and Solaris planes can provide a navigation and safety overlay required for the safe and reliable operation of autonomous vehicles / craft / robots of all types: this navigation and safety overlay can be provided to the digital twins used to control and automate vehicle movements. The system can actively detect (e.g. using a camera, SAR, etc.) and validate the position, movement, and status of any vehicle that may have lost its identifier / signal, or lost network connectivity.

[0002] 77 Attorney Docket No.391529.00003 F.11 Buildings Solaris planes can persistently and in real-time monitor, and benchmark various building parameters (usage, energy efficiency, fire risk, insurance damage, maintenance tasks), including generating data for both buildings, and the background / ambient environment. Solaris planes can include imaging payloads that enable: o Monitoring thermal signatures of buildings to help owners / users know where energy is lost and generate actual energy ratings for each, including reports and optimised plans to improve and achieve required efficiency levels or standards o Detect ageing and insulation properties of building structures improves preventative maintenance and lifetime and value of the asset o Leads to environmental charging / credits by building / asset as we move to a zero- carbon world o Change monitoring: millimetric changes in structures, ground levels etc. can be detected, including normal diurnal, seasonal changes and abnormalities, as a predictor of failure. This can be applied to the monitoring of infrastructure such as power lines, roads, railways, runways, ports, etc., and waterways / canals, where millimetric levy deformation is an indicator of structure failure or leaking of water below ground. o Security: being able to subscribe to a Solaris service that monitors your property when you are not there - e.g. for visitors, movements, deliveries, access, usage (including heat, lights, watering, etc.) to not only provide live incident management, but evidence of any event - who, where, where it / they came from and went, etc. o Flows: being able to monitor daily patterns of life around building or estate usage can enable far more efficient designs, maintenance, prevention and choice of improvements. o Fires: being able to detect fires in real-time and alert and accurately direct emergency services to the scene at the earliest stages of a fire and provide accurate information (live video stream) of the actual fire, progress, type, etc., both for the central incident room for faster, more precise response and instructions to first responders and experts. o Floods: being able to detect floods in real-time and alert and accurately direct emergency services to the scene at the earliest stages of a flood and provide accurate information (live video stream) of the actual flood, progress, type, etc., both for the 78 Attorney Docket No.391529.00003 central incident room for faster, more precise response and instructions to first responders and experts o Earth quakes / tsunamis / storms / pests / infestations o Monitoring of vegetation, growth rates, quality and being able to optimise treatment, care and scheduling of services to optimise resource usage which opens up commercial providers to service these needs o E.g. users could subscribe to a service that optimizes how and when they should water, fertilize, plant and even mow / prune / weed their gardens and may even trigger the sending of products or professionals to treat / manage their gardens at key moments as required The same applies to monitoring all forms of infrastructure such as street surfaces, drains, pipes, lights, cabling, signage, markings, etc., where preventative maintenance, optimized routing / planning and resource usage are key drivers for more efficient public services, spending and ROI. F.12 Insurers, Finance, Service providers Based on the rich data that the Solaris urban data layer (and even wider suburban and rural) offers, a range of additional possibilities such as o Insurance – remotely assessing a risk, evaluating an event and detailed actual data for improving claims assessment and disbursements o Finance – assessing the use, quality and progress of assets – buildings, vehicles, locations (e.g. traffic, footfall, goods movements…) o Services - a range of services will benefit from having precise data about say the state of a building and its land (offer roof repair, wall / painting / fencing, gardening), its performance (thermal / energy) and its safety and security (fire, water, infestation and access / use / events). 79 Attorney Docket No.391529.00003 F.13 Plane includes sensors for geophysical surveys Additionally, the Solaris plane can also include sensors such as fly magnetometers and gravimeters to measure the earth’s magnetic and gravitational field, respectively, and to map both land and oceans. The sensors may be directly mounted on the Solaris plane and are configured to provide high-resolution geophysical data over large areas. Magnetometers and gravimeters, hyperspectral and thermal imagers can be used when Solaris is monitoring seismically active areas; being able to persistently monitor seismically active areas and to generate continuous data over the many weeks leading up to an actual seismic event may enable us to build better earthquake prediction models, e.g. using machine learning. Conversely, with satellites, the data is not continuous - a typical LEO satellite with an orbital period of 120 minutes and a velocity of 27,000 Km / h might only be over the same area of the planet for a fraction of a second each day, whereas a Solaris plane can loiter directly over a target area for many weeks, providing continuous data throughout that time. Solaris can also combine multiple 3D data sets to reveal more accurate, deeper insights - e.g. terrain or structure deformation from LiDAR / Radar / SAR combined with photogrammetry, e.g. for near-real-time uses, such as: monitoring: Tectonic movements; Coastlines and erosion / risks; Waterways, rivers, levies, land features; deformations and risks of breach, slides; Buildings and infrastructure - health, leaning / movement, preventative maintenance / mitigation, optimization. Solaris planes can generate the data needed for accurate magnetic and gravimetric maps. These maps have useful properties, such as: ^ The maps vary constantly with changes in the earth’s mantle; ^ The maps are indicative of tectonic activity and risks; ^ The ocean maps are useful for sub-sea navigation – as no GPS signals are available under the ocean and inertial platforms often drift over time. ^ The maps are useful for navigation in GPS / GNSS denied environments. Magnetometers and gravimeters can be small and compact and make use of quantum sensing technologies, allowing for easier integration into the Solaris plane. 80 Attorney Docket No.391529.00003 F.14 Characterizing 3D spaces There are many new impact / climate applications which the Solaris system is ideally suited for, because the relative proximity of Solaris planes to the earth surface (compared to satellites) yields high SNR and the persistence of Solaris planes (compared to satellites) delivers deep data sets and integration times that allow for granular detection in 3D spaces. Typical applications include: ^ GHG (greenhouse gas) monitoring and pollution monitoring and characterizing columns of the atmosphere is of scientific interest, e.g. for benchmarking natural / background levels of key gases, particulates, aerosols against pollutants and monitoring man-made peaks. ^ Using LiDAR (and other technologies) to map wind speeds at varying layers - meteorological, climate change, renewable optimization (turbines), aviation efficiency. ^ Using LiDAR and / or GNSS-R techniques to measure atmospheric moisture levels - e.g. atmospheric rivers that determine large parts of the hydrological cycle in US, Asia, etc., flood vs. drought planning. ^ Measuring the dynamics of ocean / sea characteristics is key to modelling the impact of climate change actions - e.g. when to spread alkaline chemicals or materials that accelerate the sea / ocean’s ability to absorb CO2 (marine Carbon Dioxide Removal) to match optimal absorption windows and avoid excess mixing between lower layers. Or fisheries, marine plant stocks and other natural resources you’re aiming to enhance and / or protect. o And for commercial purposes - optimizing safety, energy efficiency etc., of all types of vessels (above and below marine). o Measuring ocean / sea surface characteristics - e.g. waves / roughness, currents, cycles, etc… for safe navigation, optimization ^ Heat wave / heat island monitoring - climate change, agriculture, droughts, pest migration / swarm direction (often local heat bubble driven)

Claims

81 Attorney Docket No.391529.00003 CLAIMS 1. A solar powered plane, such as a plane configured to operate in the stratosphere and including a hinged vertical stabiliser that pivots about a hinge, and where the vertical stabiliser extends both above a fuselage of the plane and also below that fuselage, and a base of the vertical stabiliser includes a skid.

2. The solar powered plane of Claim 1 in which the hinged vertical stabiliser is configured such that when the skid contacts the ground on landing, the top of the vertical stabiliser is configured to pivot forwards around the hinge, minimising damage to the plane on landing 3. The solar powered plane of Claim 1 or 2 in which the skid includes a lightweight, replaceable sacrificial layer.

4. The solar powered plane of any preceding Claim in which the vertical stabiliser is prevented from hinging during normal flight by means of either a frangible pin or a lashing.

5. The solar powered plane of any preceding Claim in which the plane includes downward facing winglets and these also are configured to act as landing skids.

6. The solar powered plane of any preceding Claim in which the plane is a dual fuselage plane with an approximately 32m - 34m wingspan and each fuselage includes a hinged vertical stabiliser.

7. The solar powered plane of any preceding Claim that includes at least one or more structural sections, each configured to be attachable, detachable and replaceable during normal servicing or operations.

8. The solar powered plane of any preceding Claim that includes a light-weight structural section, formed as a tube with a circular or elliptical cross section, with carbon fibre inner and outer surfaces, between which is a structural foam core.82 Attorney Docket No.391529.00003 9. The solar powered plane of any preceding Claim that includes downward facing structures, such as winglets, that are also configured to act as landing skids.

10. The solar powered plane of any preceding Claim that includes batteries or one or more battery packs that are configured to be positioned pre-flight in a battery position adjustment system to give an optimal mass distribution to offset or compensate for the mass and position of different payloads.

11. The solar powered plane of any preceding Claim that includes dihedral wings, and in which one or more non-airframe items are positioned inside the dihedral wings.

12. The solar powered plane of any preceding Claim including a carbon fibre structure made using a vacuum / compression moulding process, with carbon fibre pre-impregnated sheets formed in a mould around an over-sized structural foam core to form the carbon fibre structure.

13. The solar powered plane of any preceding Claim including a carbon fibre structure that comprises an outer carbon fibre shell enclosing an internal structural foam core together with a second material with a different mechanical property to the internal structural foam core or the carbon fibre shell.

14. The solar powered plane of any preceding Claim including at least one fuselage with a substantially triangular cross-section with apex at the top, and in which an array of PV cells is formed on at least part of two upward facing surfaces of the fuselage.

15. The solar powered plane of any preceding Claim in which the plane includes, or receives data from, a sensor configured to detect the approach of the plane to an autonomous ground platform (AGP) on which the plane is designed to land; and in which the sensor is further configured to generate a signal that is used to control propeller blades of the plane to be in-line with wings of the plane when the height of the plane above the AGP and / or its rate of descent to the AGP or the time to landing on the AGP meet defined criteria.83 Attorney Docket No.391529.00003 16. The solar powered plane of any preceding Claim including movable control surfaces extending from a fuselage of the plane and positioned adjacent to, but behind main wings of the plane.

17. The solar powered plane of any preceding Claim in which a surface of the plane comprises panels that are each made up of a sheet that includes a non-heat-shrinkable film substrate and a heat shrinkable border to the sheet, and in which these panels are joined or attached together to form part of a surface of the plane that is tensioned or tightened by heating the heat shrinkable border.

18. The solar powered plane of any preceding Claim including a wing-skin that has been created using the following steps: (i) unreeling a heat shrinkable plastic film on to a frame; (ii) securing the film to the frame; (iii) applying heat to the plastic film to shrink it evenly; (iv) positioning the frame over a pre-glued wing structure; (v) bringing the plastic film into contact with the pre-glued wing structure.

19. The solar powered plane of any preceding Claim including PV cells that are manufactured on or integrated with a plastic film substrate and the plastic film substrate of multiple PV cells are joined together to form a part of the wing and / or fuselage surface.

20. The solar powered plane of any preceding Claim including PV cells that are protected for high altitude flight operations with an application of a layer of lacquer.

21. The solar powered plane of any preceding Claim configured with an imaging system including a carbon fibre parabolic surface that has been sputter coated with a metallic, light reflecting coating.

22. The solar powered plane of any preceding Claim including an antenna and / or sensor formed directly onto a stretched plastic, e.g. polyester, film substrate to form part of the surface of the plane.84 Attorney Docket No.391529.00003 23. The solar powered plane of any preceding Claim including multiple sensors configured to capture a swath width that is greater than the width that a single sensor could capture, and the plane includes a local processor, such as a GPU, configured to process at least some of the data from the multiple sensors into a single dataset covering the entire swath.

24. The solar powered plane of any preceding Claim configured to fly a path that enables the plane to transmit data back down to a mobile ground station at a defined location.

25. The solar powered plane of any preceding Claim configured to send data to, or receive data from, one or more different solar powered planes, and for one or more of those different planes to transmit data to, or receive data from, a ground station or other ground based system, or a satellite.

26. The solar powered plane of any preceding Claim configured to operate with a launch system including a secondary device, comprising a propulsion system with a propeller optimised for take-off and not for stratospheric flight and a secondary battery, in which the secondary device is configured to be attached to the plane and to provide some or all take-off thrust for the plane, and the secondary device draws its power from one or more batteries in the plane and not its secondary battery, but is configured to re-charge one or more batteries in the plane from its secondary battery.

27. The solar powered plane of any preceding Claim configured to be launched using the steps of (a) raising the plane tail first and then (b) releasing the plane at launch altitude so that it initially flies down substantially nose-first, and then attains approximately level flight.

28. The solar powered plane of any preceding Claim configured to land on to an Autonomous Ground Platform (AGP); in which the AGP is configured to move along a runway at a velocity that matches the plane that is coming in to land, with either the plane and / or the AGP operating an imaging unit that enables, if in the plane, the plane to track the position and motion of the AGP and / or, if in the AGP, for the AGP to track the position and motion of the plane, to ensure that the plane lands safely on the AGP.85 Attorney Docket No.391529.00003 29. The solar powered plane of any preceding Claim configured to land on a ground handling vehicle, the vehicle including (i) a wheeled chassis, (ii) fuselage holders extending from the chassis and (iii) a pair of lateral spars extending from the wheeled chassis, and (iv) a series of support arms mounted on the chassis and lateral spars and configured to support the wings of the plane.

30. The solar powered plane of any preceding Claim configured to generate training data for an AI based system, in which the plane is configured to (a) capture data for a region over a continuous period that is at least 10 times longer than the continuous period for which a light aircraft could capture data for that region and to (b) capture a quantity of data for that region that is at least 10 times greater than the quantity of data that a constellation of low earth orbit satellites could capture over the same continuous period.

31. The solar powered plane of any preceding Claim configured to generate inference data for an AI based system, in which the plane is configured to (a) capture data for a region over a continuous period that is at least 10 times longer than the continuous period for which a light aircraft could capture data for that region and to (b) capture a quantity of data for that region that is at least 10 times greater than the quantity of data that a constellation of low earth orbit satellites could capture over the same continuous period.

32. The solar powered plane of any preceding Claim configured to enable the detection or monitoring of a natural disaster event by measuring real-time data associated with a region of interest, in which the plane includes a 3D imaging subsystem and a 2D imaging unit.

33. The solar powered plane of any preceding Claim configured to enable the detection of dark sea-going vessels by including (i) an imaging system (e.g. synthetic aperture radar) for detecting and tracking sea vessels; and (ii) a receiver for automatic identification system (AIS, S-AIS or VDES) signals; and in which the plane is configured to process or send data from the imaging system and the receiver to enable vessels that are tracked by the plane but are not sending AIS, S-AIS or VDES signal to be identified as potential dark vessels.

34. The solar powered plane of any preceding Claim including a system designed to be released from the plane to disable a balloon.86 Attorney Docket No.391529.00003 35. The solar powered plane of any preceding Claim forming part of a constellation of solar powered planes, each configured to operate in the stratosphere and configured to detect their position with reference to a star map, and to transmit that position data with time signal data to enable a user to infer their location using these position and time signals, without the recourse to the GPS or other GNSS systems.

36. A solar powered plane that includes at least one or more structural sections, each configured to be attachable, detachable and replaceable during normal servicing or operations.

37. A solar powered plane that includes a light-weight structural section, formed as a tube with a circular or elliptical cross section, with carbon fibre inner and outer surfaces, between which is a structural foam core.

38. A solar powered plane that includes downward facing structures, such as winglets and / or a vertical stabiliser, that are also configured to act as landing skids.

39. A solar powered plane that includes batteries or one or more battery packs that are configured to be positioned pre-flight in a battery position adjustment system to give an optimal mass distribution to offset or compensate for the mass and position of different payloads.

40. A solar powered plane with dihedral wings and that includes one or more non-airframe items positioned inside the dihedral wings.

41. A solar powered plane including a carbon fibre structure made using a vacuum / compression moulding process, with carbon fibre pre-impregnated sheets formed in a mould around an over-sized structural foam core.

42. A solar powered plane including a carbon fibre structure that comprises an outer carbon fibre shell enclosing an internal structural foam core together with a second material with a different mechanical property to the internal structural foam core or the carbon fibre shell.87 Attorney Docket No.391529.00003 43. A solar powered plane including at least one fuselage with a substantially triangular cross-section with apex at the top, and in which an array of PV cells is formed on at least part of an upward facing surface of the fuselage.

44. A solar powered plane in which the plane includes, or receives data from, a sensor configured to detect the approach of the plane to an autonomous ground platform (AGP) on which the plane is designed to land; and in which the sensor is further configured to generate a signal that is used to control the propeller blades to be in-line with the wings of the plane when the height of the plane above the AGP and / or its rate of descent to the AGP or the time to landing on the AGP meet defined criteria.

45. A solar powered plane with a fuselage and main wings, including movable control surfaces extending from a fuselage of the plane and positioned adjacent to, but behind the main wings of the plane.

46. A solar powered plane in which a surface of the plane comprises panels that are each made up of a sheet that includes a non-heat-shrinkable film substrate and a heat shrinkable border to the sheet, and in which these panels are joined or attached together to form part of a surface of the plane that is tensioned or tightened by heating the heat shrinkable border.

47. A solar powered plane including a wing-skin that has been created using the following steps: (i) unreeling a heat shrinkable plastic film on to a frame; (ii) securing the film to the frame; (iii) applying heat to the plastic film to shrink it evenly; (iv) positioning the frame over a pre-glued wing structure; (v) bringing the plastic film into contact with the pre-glued wing structure.

48. A solar powered plane including PV cells that are manufactured on or integrated with a plastic film substrate and the plastic film substrate of multiple PV cells are joined together to form a part of a wing and / or a fuselage surface.88 Attorney Docket No.391529.00003 49. A solar powered plane including PV cells that are protected for high altitude flight operations with an application of a layer of lacquer.

50. A solar powered plane configured with an imaging system including a carbon fibre parabolic surface that has been sputter coated with a metallic, light reflecting coating.

51. A solar powered plane including an antenna and / or sensor formed directly onto a stretched plastic, e.g. polyester, film substrate to form part of the surface of the plane.

52. A solar powered plane including multiple sensors configured to capture a swath width that is greater than a width that a single sensor could capture, and the plane includes a local processor, such as a GPU, configured to process at least some of the data from the multiple sensors into a single dataset covering the entire swath.

53. A solar powered plane configured to fly a path that enables the plane to transmit data back down to a mobile ground station at a defined location.

54. A solar powered plane configured to send data to, or receive data from, one or more different solar powered planes, and for one or more of those different planes to transmit data to, or receive data from, a ground station or other ground based system, or a satellite.

55. A solar powered plane configured to operate with a launch system including a secondary device, comprising a propulsion system with a propeller optimised for take-off and not for stratospheric flight and a secondary battery, in which the secondary device is configured to be attached to the plane and to provide some or all take-off thrust for the plane, and the secondary device draws its power from one or more batteries in the plane and not its secondary battery, but is configured to re-charge one or more batteries in the plane from its secondary battery.

56. A solar powered plane configured to be launched using the steps of (a) raising the plane tail first and then (b) releasing the plane at launch altitude so that it initially flies down substantially nose-first, and then attains approximately level flight.89 Attorney Docket No.391529.00003 57. A solar powered plane configured to land on to an Autonomous Ground Platform (AGP); in which the AGP is configured to move along a runway at a velocity that matches the plane that is coming in to land, with either the plane and / or the AGP operating an imaging unit that enables, if in the plane, the plane to track the position and motion of the AGP and / or, if in the AGP, for the AGP to track the position and motion of the plane, to ensure that the plane lands safely on the AGP.

58. A solar powered plane configured to land on a ground handling vehicle, the vehicle including (i) a wheeled chassis, (ii) fuselage holders extending from the chassis and (iii) a pair of lateral spars extending from the wheeled chassis, and (iv) a series of support arms mounted on the chassis and lateral spars and configured to support the wings of the plane.

59. A solar powered plane configured to generate training data for an AI based system, in which the plane is configured to (a) capture data for a region over a continuous period that is at least 10 times longer than the continuous period for which a light aircraft could capture data for that region and to (b) capture a quantity of data for that region that is at least 10 times greater than the quantity of data that a constellation of low earth orbit satellites could capture over the same continuous period.

60. A solar powered plane configured to generate inference data for an AI based system, in which the plane is configured to (a) capture data for a region over a continuous period that is at least 10 times longer than the continuous period for which a light aircraft could capture data for that region and to (b) capture a quantity of data for that region that is at least 10 times greater than the quantity of data that a constellation of low earth orbit satellites could capture over the same continuous period.

61. A solar powered plane configured to enable the detection or monitoring of a natural disaster event by measuring real-time data associated with a region of interest, in which the plane includes a 3D imaging subsystem and a 2D imaging unit.

62. A solar powered plane configured to enable the detection of dark sea-going vessels by including (i) an imaging system (e.g. synthetic aperture radar) for detecting and tracking sea vessels; and (ii) a receiver for automatic identification system (AIS, S-AIS or VDES) signals;90 Attorney Docket No.391529.00003 and in which the plane is configured to process or send data from the imaging system and the receiver to enable vessels that are tracked by the plane but are not sending AIS, S-AIS or VDES signal to be identified as potential dark vessels.

63. A solar powered plane including a system designed to be released from the plane to disable a balloon.

64. A solar powered plane forming part of a constellation of solar powered planes, each configured to operate in the stratosphere and configured to detect their position with reference to a star map, and to transmit that position data with time signal data to enable a user to infer their location using these position and time signals, without the recourse to the GPS or other GNSS systems.

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