A method for calculating a bypass track

Abstract

The present invention belongs to the technical field of flight management systems, and particularly relates to a method for calculating a bypass track. This method extracts flight plan information, calculates the turning direction based on the azimuth information of the front and rear flight segments, further calculates the central angle corresponding to the transition arc, calculates the turning radius according to the current ground speed of the aircraft and the maximum roll angle, and calculates the coordinates of the turning starting point, the coordinates of the ending point, and the center coordinates of the arc. This method increases the determinability and repeatability of the track, and at the same time improves the flight quality of the aircraft in the turning section.

Description

Technical Field

[0001] The present invention belongs to the technical field of flight management systems, and particularly relates to a method for calculating a tangent-cut track. Background Art

[0002] Tangent turn transition is a very important transition method in civil aviation flight procedures. It increases the determinability and repeatability of the track, and improves the flight quality of the carrier aircraft in the turning section. Therefore, tangent turn transition is an indispensable part of the carrier aircraft flight management system.

[0003] Currently, in domestic manned aircraft, straight flight segments are mainly used, and the vast majority of manned aircraft do not yet have the ability of tangent turn transition. Summary of the Invention

[0004] The object of the present invention is to provide a method for calculating a tangent-cut track, which increases the determinability and repeatability of the track, and at the same time improves the flight quality of the carrier aircraft in the turning section.

[0005] The technical solution of the present invention: In order to achieve the above object of the invention, a method for calculating a tangent-cut track is proposed, which includes the following steps:

[0006] Step 1: According to the flight plan data, obtain the course angle of the previous flight segment and the course angle of the subsequent flight segment respectively;

[0007] Step 2: Determine the turning direction from the previous flight segment to the subsequent flight segment according to the course angle of the previous flight segment and the course angle of the subsequent flight segment;

[0008] Step 3: Calculate the central angle corresponding to the transition arc of the tangent-cut track generated from the previous flight segment to the subsequent flight segment;

[0009] Step 4: Calculate the turning radius of the aircraft;

[0010] Step 5: Calculate the starting point coordinates of the transition arc of the tangent-cut track according to the central angle calculated in Step 3 and the turning radius of the aircraft calculated in Step 4;

[0011] Step 6: Calculate the ending point coordinates of the transition arc of the tangent-cut track according to the central angle calculated in Step 3 and the turning radius of the aircraft calculated in Step 4;

[0012] Step 7: Calculate the center coordinates of the transition arc of the tangent-cut track according to the turning radius of the aircraft calculated in Step 4 and the starting point coordinates of the transition arc of the tangent-cut track calculated in Step 5 or the ending point coordinates of the transition arc of the tangent-cut track calculated in Step 6;

[0013] Step 8: Based on the turning direction from the previous flight segment to the subsequent flight segment, the central angle corresponding to the transition arc of the tangent flight segment, the turning radius of the aircraft, the starting point coordinates of the transition arc of the tangent flight segment, the ending point coordinates of the transition arc of the tangent flight segment, and the center coordinates of the transition arc of the tangent flight segment, combined with the flight plan data, finally calculate the complete flight track of the transition arc of the tangent flight segment.

[0014] In a possible embodiment, in the said Step 1, denote the coordinates of the ending point of the previous flight segment as P fix , denote the course angle of the previous flight segment as χ i , and denote the course angle of the subsequent flight segment as χ f ; In the said Step 2, the specific process of determining the turning direction from the previous flight segment to the subsequent flight segment includes:

[0015] ① When , if 0 < χ f - χ i < π, the aircraft turns right; if or π < χ f - χ i < 2π, the aircraft turns left;

[0016] ② When , if 0 < χ f - χ i < π or the aircraft turns right; if -π < χ f - χ i < 0, the aircraft turns left;

[0017] ③ When , if -π < χ f - χ i < 0 or the aircraft turns left; if 0 < χ f - χ i < π, the aircraft turns right;

[0018] ④ When , if -π < χ f - χ i < 0, the aircraft turns left, if or -2π < χ f - χ i < -π, the aircraft turns right.

[0019] In a possible embodiment, in the said Step 3, denote the central angle corresponding to the transition arc as Δχ, and the calculation process of the central angle corresponding to the transition arc of the tangent flight segment is;

[0020] Δχ = |χ f - χ i |.

[0021] In a possible embodiment, in the step 4, the process of calculating the turning radius of the aircraft specifically includes:

[0022] Let r be the turning radius of the aircraft, the current ground speed of the aircraft be V, the acceleration due to gravity be g, and the maximum bank angle of the aircraft be φ; calculate the turning radius r of the aircraft according to the following formula:

[0023] r = V 2 / g·tan(φ).

[0024] In a possible embodiment, in the step 5, the process of calculating the starting point coordinates of the transition arc of the tangent bypass segment specifically includes:

[0025] The distance Y1 from the end point P of the previous flight segment fix to the starting point P1 of the transition arc of the tangent bypass segment is The distance course angle from the end point P of the previous flight segment fix to the starting point P1 of the transition arc of the tangent bypass segment is π + χ i , given that P fix has the longitude and latitude of The longitude and latitude of P1 is R e is the radius of the earth, calculate the starting point coordinates of the transition arc of the tangent bypass segment according to the following formula:

[0026]

[0027]

[0028] In a possible embodiment, in the step 6, the process of calculating the ending point coordinates of the transition arc of the tangent bypass segment specifically includes;

[0029] The distance Y2 from the end point P of the previous flight segment fix to the ending point P2 of the transition arc of the tangent bypass segment is The distance course angle from the end point P of the previous flight segment fix to the ending point P2 of the transition arc of the tangent bypass segment is χ f , calculate the ending point coordinates of the transition arc of the tangent bypass segment according to the following formula:

[0030]

[0031]

[0032] In a possible embodiment, in the step 7, the process of calculating the coordinates of the center P0 of the transition arc of the tangent bypass segment using the starting point coordinates of the transition arc of the tangent bypass segment specifically includes:

[0033] Let the course angle from the starting point P1 of the transition arc of the side-cutting flight path segment to the center point P0 of the transition arc of the side-cutting flight path segment

[0034] When At this time

[0035] When At this time

[0036] When At this time

[0037] When At this time

[0038] The distance from the starting point P1 of the transition arc of the side-cutting flight path segment to the center point P0 of the transition arc of the side-cutting flight path segment is known as r. Calculate the coordinates of the center point P0 of the transition arc of the side-cutting flight path segment according to the following formula:

[0039]

[0040]

[0041] In a possible embodiment, in the said step 7, the calculation process of calculating the coordinates of the center point P0 of the transition arc of the side-cutting flight path segment by using the coordinates of the end point of the transition arc of the side-cutting flight path segment specifically includes:

[0042] Let the course angle from the end point P2 of the transition arc of the side-cutting flight path segment to the center point P0 of the transition arc of the side-cutting flight path segment Then there is:

[0043] When At this time

[0044] When At this time

[0045] When At this time

[0046] When At this time

[0047] The distance from the end point P2 of the transition arc of the side-cutting flight path segment to the center point P0 of the transition arc of the side-cutting flight path segment is known as r. Calculate the coordinates of the center point P0 of the transition arc of the side-cutting flight path segment according to the following formula:

[0048]

[0049]

[0050] The advantages and effects of the present invention can be as follows:

[0051] (1) Increase the determinability and repeatability of the flight track;

[0052] (2) Accurately calculate the turning arc during tangent turning flight to improve the pilot's perception ability.

[0053] (3) Improve the flight quality of the carrier aircraft during the turning section. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 Schematic diagram of tangent turning transition. DETAILED DESCRIPTION OF THE INVENTION

[0055] The present invention will be further described below in conjunction with the drawings of the specification.

[0056] As Figure 1 shown, a method for calculating a tangent flight track has the following specific operation steps:

[0057] Step 1: According to the flight plan data, obtain the course angles of the previous flight segment and the subsequent flight segment respectively. Refer to Figure 1 shown, denote the end coordinates of the previous flight segment as P fix , denote the course angle of the previous flight segment as χ i , denote the course angle of the subsequent flight segment as χ f ;

[0058] Step 2: Calculate the turning direction according to the course angles of the previous and subsequent flight segments.

[0059] Calculation method:

[0060] ① When , if 0 < χ f - χ i < π, the aircraft turns right; if or π < χ f - χ i < 2π, the aircraft turns left;

[0061] ② When , if 0 < χ f - χ i < π or the aircraft turns right; if -π < χ f - χ i < 0, the aircraft turns left;

[0062] ③ When , if -π < χ f - χ i < 0 or the aircraft turns left; if 0 < χ f - χi <π, the aircraft turns right.

[0063] ④ When If -π < χ f -χ i < 0, the aircraft turns left. If Or -2π < χ f -χ i < -π, the aircraft turns right.

[0064] Step 3: The central angle Δχ corresponding to the transition arc, Δχ = |χ f -χ i |.

[0065] Step 4: Calculate the turning radius of the aircraft:

[0066] Assume that r is the turning radius of the aircraft, the current ground speed of the aircraft is V, the acceleration due to gravity is g, and the maximum bank angle of the aircraft is φ. Then:

[0067] r = V 2 / g·tan(φ)

[0068] Step 5: Calculate the coordinates of the turning starting point.

[0069] As shown by Figure 1 The distance Y1 from the fixed point P fix to the turning starting point P1 is The course angle of the distance from the fixed point P fix to the turning starting point P1 is π + χ i Set the longitude and latitude of P fix as The longitude and latitude of P1 is R e is the radius of the earth, then:

[0070]

[0071]

[0072] Step 6: Calculate the coordinates of the turning end point.

[0073] As can be seen from Figure 1 The distance Y2 from the fixed point P fix to the turning starting point P2 is The course angle of the distance from the fixed point P fix to the turning starting point P2 is χ f Assume the longitude and latitude of P2 is Then:

[0074]

[0075]

[0076] Step 7: Calculate the center point coordinates of the arc based on the starting point coordinates P1 of the transition arc of the tangent-offset flight segment.

[0077] The course angle χ from the starting point P1 of the turn to the center point P0 of the arc P0

[0078] When ,

[0079] When ,

[0080] When ,

[0081] When , Also, since the distance from the starting point P1 of the turn to the center point P0 of the arc is known as r, then:

[0082]

[0083]

[0084] Step 8: Calculate the center point coordinates of the arc based on the ending point coordinates P2 of the transition arc of the tangent-offset flight segment.

[0085] The course angle χ' from the ending point P2 of the turn to the center point P0 of the arc P0 , then:

[0086] When , When , When , When , Also, since the distance from the ending point P2 of the turn to the center point P0 of the arc is known as r, then:

[0087]

[0088]

[0089] Step 9: Based on the turning direction from the previous flight segment to the next flight segment, the central angle corresponding to the transition arc of the tangent-offset flight segment, the turning radius of the aircraft, the starting point coordinates of the transition arc of the tangent-offset flight segment, the ending point coordinates of the transition arc of the tangent-offset flight segment, and the center coordinates of the transition arc of the tangent-offset flight segment, finally obtain the complete track of the transition arc of the tangent-offset flight segment.

Claims

1. A method for calculating a by-pass track, characterized in that: It includes the following steps: Step 1: Obtain the course angle of the previous flight segment and the course angle of the subsequent flight segment respectively according to the flight plan data; Step 2: Determine the turning direction from the previous flight segment to the subsequent flight segment according to the course angle of the previous flight segment and the course angle of the subsequent flight segment; Step 3: Calculate the central angle corresponding to the transition circular arc of the tangent bypass flight segment generated by the transition from the previous flight segment to the subsequent flight segment; Step 4: Calculate the turning radius of the aircraft; Step 5: Calculate the starting point coordinates of the transition circular arc of the tangent bypass flight segment according to the central angle calculated in Step 3 and the turning radius of the aircraft calculated in Step 4; Step 6: Calculate the ending point coordinates of the transition circular arc of the tangent bypass flight segment according to the central angle calculated in Step 3 and the turning radius of the aircraft calculated in Step 4; Step 7: Calculate the center coordinates of the transition circular arc of the tangent bypass flight segment according to the turning radius of the aircraft calculated in Step 4 and the starting point coordinates of the transition circular arc of the tangent bypass flight segment calculated in Step 5 or the ending point coordinates of the transition circular arc of the tangent bypass flight segment calculated in Step 6; Step 8: Finally calculate the complete track of the transition circular arc of the tangent bypass flight segment according to the turning direction from the previous flight segment to the subsequent flight segment, the central angle corresponding to the transition circular arc of the tangent bypass flight segment, the turning radius of the aircraft, the starting point coordinates of the transition circular arc of the tangent bypass flight segment, the ending point coordinates of the transition circular arc of the tangent bypass flight segment, and the center coordinates of the transition circular arc of the tangent bypass flight segment, in combination with the flight plan data.

2. The side-cut flight path calculation method according to claim 1, wherein: In the step 1, denote the end coordinates of the previous flight segment as P fix , denote the course angle of the previous flight segment as χ i , denote the course angle of the subsequent flight segment as χ f ; In the step 2, the specific process of determining the turning direction from the previous flight segment to the subsequent flight segment includes: ①When If \(0 < \chi\) f -\(\chi\) i \(< \pi\), the aircraft turns right; if or \(\pi < \chi\) f -\(\chi\) i \(< 2\pi\), the aircraft turns left; ②When If 0 < χ f -χ i < π or the aircraft turns right; if -π < χ f -χ i < 0, the aircraft turns left; ③When If -π < χ f -χ i < 0 or the aircraft turns left; if 0 < χ f -χ i < π, the aircraft turns right; ④When If -π < χ f -χ i < 0, the aircraft turns left. If or -2π < χ f -χ i < -π, the aircraft turns right.

3. The side-cut flight path calculation method according to claim 2, wherein: In Step 3, denote the central angle of the transition circular arc as Δχ, and the calculation process of the central angle corresponding to the transition circular arc of the tangent bypass flight segment is as follows; Δχ = |χ f - χ i |。 4. The side-cut flight path calculation method according to claim 3, wherein: In Step 4, the specific process of calculating the turning radius of the aircraft includes: Let r be the turning radius of the aircraft, the current ground speed of the aircraft be V, the gravitational acceleration be g, and the maximum bank angle of the aircraft be φ; calculate the turning radius r of the aircraft according to the following formula: r = V 2 / g·tan(φ).

5. A method for calculating a side-cut flight path according to claim 4, characterized in that: In Step 5, the specific process of calculating the starting point coordinates of the transition circular arc of the tangent bypass flight segment includes: The end point P of the forward flight segment fix The distance Y1 from the end point P of the forward flight segment to the starting point P1 of the transition arc of the tangent flight segment is The end point P of the forward flight segment fix The course angle of the distance from the end point P of the forward flight segment to the starting point P1 of the transition arc of the tangent flight segment is π + χ i , given that the longitude and latitude of P fix is The longitude and latitude of P1 is R e is the radius of the earth, and the coordinates of the starting point of the transition arc of the tangent flight segment are calculated according to the following formula:

6. The side-cut flight path calculation method according to claim 5, wherein: In Step 6, the specific process of calculating the ending point coordinates of the transition circular arc of the tangent bypass flight segment includes; The end point P of the forward flight segment fix The distance Y2 from the end point P of the forward flight segment to the termination point P2 of the transition arc of the tangent flight segment is The end point P of the forward flight segment fix The course angle of the distance from the end point P of the forward flight segment to the termination point P2 of the transition arc of the tangent flight segment is χ f , and the coordinates of the termination point of the transition arc of the tangent flight segment are calculated according to the following formula:

7. A method for calculating a side-cut flight path according to claim 1, characterized in that: In Step 7, the specific process of calculating the center P0 coordinates of the transition circular arc of the tangent bypass flight segment using the starting point coordinates of the transition circular arc of the tangent bypass flight segment includes: Let the course angle from the starting point P1 of the transition arc of the tangent bypass segment to the center point P0 of the transition arc of the tangent bypass segment When then When , When then When , The distance from the starting point P1 of the transition circular arc of the tangent bypass flight segment to the center P0 of the transition circular arc of the tangent bypass flight segment is known as r, and calculate the coordinates of the center P0 of the transition circular arc of the tangent bypass flight segment according to the following formula:

8. A method for calculating a side-cut flight path according to claim 1, characterized in that: In Step 7, the specific process of calculating the center P0 coordinates of the transition circular arc of the tangent bypass flight segment using the ending point coordinates of the transition circular arc of the tangent bypass flight segment includes: Let the course angle from the termination point P2 of the transition arc of the tangent bypass segment to the center point P0 of the transition arc of the tangent bypass segment Then we have: When then When then When then When then The distance from the ending point P2 of the transition circular arc of the tangent bypass flight segment to the center P0 of the transition circular arc of the tangent bypass flight segment is known as r, and calculate the coordinates of the center P0 of the transition circular arc of the tangent bypass flight segment according to the following formula:

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