In-flight Refueling Boom Tensioning via Aerodynamic Surfaces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing in-flight refueling systems using articulated booms face issues such as excessive boom movement dynamics affecting flying performance, cable faults compromising safety, complex wind-up and release systems, and high costs due to high rotational torque and weight requirements.
Innovation Solution
A method and device utilizing a cable with flexural rigidity and resilient properties, where the cable is initially released and kept tensioned by aerodynamic surfaces, with controlled tension during deployment, and then maintained at low tension for refueling, using movable aerodynamic surfaces for control, and a law-based system for precise positioning, eliminating the need for continuous cable wind-up and release during refueling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the cable wind-up and release system is made complex to handle all fault situations, then reliability is improved, but device complexity increases
Solution Approach 1:
The patent extracts the cable tensioning function from the complex wind-up and release system, using only a simple winch mechanism that maintains constant tension without needing to actively control cable length. This removes the complex fault-handling requirements while maintaining safety through passive tensioning.
Solution Approach 2:
The cable system is designed to self-regulate tension through the interaction between the winch, aerodynamic forces on the boom, and gravity. The system automatically maintains appropriate tension without requiring active control or complex fault detection mechanisms.
2Productivity
If the motor and associated parts are designed to provide high rotational torque and fast speed, then productivity is improved, but weight and size increase
Solution Approach 1:
The patent employs dynamic tensioning where the cable tension varies automatically with the operational phase. During deployment, aerodynamic forces provide the necessary tension, eliminating the need for high-torque motors. The system adapts tension levels to match actual operational requirements.
Solution Approach 2:
The cable tension parameter is dynamically adjusted through the operational process rather than maintained at high levels. Tension is high during deployment due to aerodynamic forces, then reduces to low tension during refueling, eliminating the need for continuously high-power motor components.
3Reliability
If the cable is kept constantly tensioned during deployment, then reliability is improved, but force requirements increase
Solution Approach 1:
The patent uses aerodynamic forces acting on the boom as a counterbalancing element against the cable tension. The aerodynamic pressure differential creates forces that naturally counteract the weight and tension requirements, reducing the net force that must be managed by the cable system.
Solution Approach 2:
The system utilizes aerodynamic pressure forces (a form of pneumatic/hydraulic force) to manage cable tension. The air pressure differential generated by the boom's movement and configuration provides the necessary tensioning force, replacing the need for mechanical tensioning systems.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces tugging on the boom, enhances safety by preventing cable catching, simplifies the system, and reduces size and weight, leading to improved flying performance and cost-effectiveness by minimizing the need for high-torque components.
Implementation Method 1
the boom has aerodynamic control surfaces along its structural member which are controlled by the operator so as to be able to direct said boom towards the receptacle of the receiver aircraft
Implementation Method 2
The cable (18) has a flexural rigidity and resilient properties which, in combination with its cross-section, enable it, once extended, to form a substantially flat curve
Implementation Method 3
The cable (18) has a flexural rigidity and resilient properties which, in combination with its cross-section, enable it, once extended, to form a substantially flat curve
Implementation Method 4
the cable is kept constantly tensioned for the duration of this operation owing to the force supplied by the movable aerodynamic surfaces and/or owing to the force of gravity acting on the said boom
Data Source
AI summary
A method and device for in-flight including movable aerodynamic surfaces boom refueling operations using an articulated boom and a cable is disclosed. The method includes: (a) from a completely stowed-away and retracted position of the boom, the cable is initially released, thereby starting to lower the boom, such that the said cable is kept tensioned during the whole of step (a) by the force supplied by the movable aerodynamic surfaces and/or the force of gravity acting on the boom; (b) after reaching the maximum deployed position of the boom, or the bottom end of the flight envelope of the boom, release of the cable is stopped; (c) while keeping the length of released cable fixed, the boom is brought into a suitable position for commencing the maneuvers for refueling of the receiver aircraft; (d) the manoeuvre for connecting the boom to the receptacle of the receiver aircraft is started by control of the movable aerodynamic surfaces; and (e) once the connection has been established, the transfer of fuel to the receiver aircraft is started.