Computing and displaying climb dive marker elevation

• US 10,794,726 B2
• Filed: 01/30/2018
• Issued: 10/06/2020
• Est. Priority Date: 07/21/2017
• Status: Active Grant

• Current Assignee: Elbit Systems of America LLC (Elbit Systems Limited)
• Original Assignee: Elbit Systems of America LLC (Elbit Systems Limited)
• Inventors: Pearson, John Timothy, Butler, Lawerance Ray, Grandin, Keith Thomas, Robb, Michael Allen
• Primary Examiner(s): Alharbi, Adam M
• Application Number:
  US15/883,989
• Publication Number:
  US 20190025077A1
• Time in Patent Office: 980 Days
• CPC Class Codes: B64D 43/00 Arrangements or adaptations of instruments arrangements of cameras B64D47/08; aeronautical measuring instruments per se G01C
• CPC Class Codes: G01C 23/005 Flight directors indicating arrangements specially adapted for rotary gyroscopes G01C19/32
• CPC Class Codes: G02B 2027/0141 characterised by the informative content of the display
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence

Abstract

A method of calculating a climb-dive marker (CDM) that is visibly present on a display even as the aircraft approaches a roll angle of +/−90° is provided. An exemplary CDM method comprises obtaining, an X-axis velocity, a Y-axis velocity, and a Z-axis velocity in aircraft body coordinates of an aircraft; calculating a CDM elevation; and displaying, by the controller, the calculated CDM elevation. The method can further comprise obtaining an angle of attack (AoA) of the aircraft and a roll angle of the aircraft, wherein the AoA is set as the value of the CDM elevation when the roll angle is within a preset range. The CDM elevation may also be calculated using a combination of the AOA and the CDM formula when roll angle is within a second preset range.

Claims

1. A climb-dive marker (CDM) method, comprising:

obtaining, by a controller, an X-axis velocity in aircraft body coordinates, a Y-axis velocity in aircraft body coordinates, and a Z-axis velocity in aircraft body coordinates of an aircraft;

calculating, by the controller, a CDM elevation using a CDM formula;

2. The method of claim 1, further comprising obtaining an angle of attack (AoA) of the aircraft and a roll angle of the aircraft, wherein the AoA is set as the value of the CDM elevation when the roll angle is greater than a first preset value and less than a second preset value.

5. The method of claim 1, further comprising:

obtaining an AoA of the aircraft; and

calculating the CDM elevation based in part on the CDM formula and based in part on the AoA.

6. The method of claim 1, further comprising:

obtaining an AoA of the aircraft;

obtaining a roll angle of the aircraft; and

calculating the CDM elevation using a blended formula when the roll angle is less than a first preset value and greater than a second preset value, wherein the blended formula is;

X*CDM_el+Y*AoA,

wherein 0≤

X≤

1, wherein 0≤

Y≤

1, and wherein X+Y=1.

7. The method of claim 5, wherein X→

1 as the roll angle approaches the first preset value, and wherein Y→

1 as the roll angle approaches the second preset value.

8. The method of claim 5, wherein X=0.5, and wherein Y=0.5.

9. The method of claim 5, wherein the first preset value is within a range of 55°

to 80°

, and wherein the second preset value is within a range of 100°

to 125°

, and wherein the second preset value is greater than the first preset value.

10. The method of claim 1, wherein the X-axis velocity, the Y-axis velocity, and the Z-axis velocity of the aircraft are obtained from a navigation system of the aircraft.

11. The method of claim 1, further comprising displaying the calculated CDM elevation on a heads-up display (HUD).

12. The method of claim 1, further comprising displaying the calculated CDM elevation on a panel screen of the aircraft.

14. The device of claim 12, wherein the processor is further configured to obtain an angle of attack (AoA) of the aircraft and a roll angle of the aircraft, wherein the AoA is set as the value of the CDM elevation when the roll angle is greater than a first preset value and less than a second preset value.

16. The device of claim 14, wherein the CDM elevation is calculated using a combination of the AOA and the CDM formula when roll angle is greater than the third preset value and less than the first preset value, or when the roll angle is greater than the second preset value and less than the fourth preset value.

17. The device of claim 12, wherein the processor is further configured to:

obtain an AoA of the aircraft; and

calculate the CDM elevation based in part on the CDM formula and based in part on the AoA.

18. The device of claim 12, wherein the processor is further configured to:

obtain an AoA of the aircraft;

obtain a roll angle of the aircraft; and

calculate the CDM elevation using a blended formula when the roll angle is less than a first preset value and greater than a second preset value, wherein the blended formula is;

X*CDM_el+Y*AoA,

wherein 0≤

X≤

1, wherein 0≤

Y≤

1, and wherein X+Y=1.

19. The device of claim 17, wherein X→

1 as the roll angle approaches the first preset value, and wherein Y→

1 as the roll angle approaches the second preset value.

3. The method of 2, wherein the CDM elevation is calculated using the CDM formula when the roll angle is less than a third preset value or greater than a fourth preset value.

4. The method of claim 3, wherein the CDM elevation is calculated using a combination of the AOA and the CDM formula when roll angle is greater than the third preset value and less than the first preset value, or when the roll angle is greater than the second preset value and less than the fourth preset value.

13. A device comprising:

a memory storing executable instructions; and

a processor coupled to the memory and configured to;

obtain an X-axis velocity in aircraft body coordinates, a Y-axis velocity in aircraft body coordinates, and a Z-axis velocity in aircraft body coordinates of an aircraft;

calculate a climb-dive market (CDM) elevation using a CDM formula;

CDM_ei=tan^-1—

—

+tan<

p tan^-1—

and

V_xb Vxb

transmit, to a controller, the calculated CDM elevation for display.

15. The device of 13, wherein the CDM elevation is calculated using the CDM formula when the roll angle is less than a third preset value or greater than a fourth preset value.