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Test Flight Examples

We next list a typical set of test flights for a 25 kg UAV and ground control station (GCS) capable of full autonomous takeoff, mission operation, and landing. The sequence follows the logic just set out and will provide all the information needed to complete the system description that will be used with the completed UAS.

UAS Performance Flight Test (MANUAL Mode)

The very first set of self-powered tests seek to assure the design team that the airframe has basic airworthiness.

  • 1. Ground handling. (a) Aircraft speed and direction controllable on ground, (b) UAV can idle and remain stationary on a grass surface suitable for takeoff without intervention, (c) control can be maintained in a fast taxi situation, (d) undercarriage is serviceable, and (e) no loss of aircraft control signal.
  • 2. Aircraft handling and performance at takeoff, low-speed flight, cruise, high-speed flight, and landing to a satisfactory level for the UAV pilot to continue with flight testing.
  • 3. With aircraft in chosen take-off configuration with flaps at specified angle, measure the take-off run. Keep flaps in take-off (mid) position. (a) Take-off run measured, (b) take-off run to clear 10.7 m obstacle, (c) autopilot-measured average climb rate recorded within the first 5 s after takeoff, and (d) aircraft climb average airspeed measured by autopilot.
  • 4. Aircraft to clean configuration. Climb to height over airfield. (a) Max. clean climb rate into wind measured by autopilot.
  • 5. Straight and level clean cruise speed measured. (a) full control inputs on ailerons, rudder, and pitch, both directions. Confirm response is adequate and equal in both directions, (b) fly UAV within approach to clean stall; check full control authority, and (c) autopilot-measured air speed.
  • 6. Aircraft clean max. cruise speed measured by autopilot (no flutter seen). (a) Apply suitable control inputs to confirm handling suitable.
  • 7. Gliding. Clean setup over the airfield at maximum suitable height. (a) Maintain straight and level into wind, (b) autopilot-measured average descent rate, and (c) autopilot-measured approximate airspeed.
  • 8. Gliding. Take-off flap set up over the airfield at a suitable height. (a) Maintain straight and level into wind, (b) autopilot-measured average descent rate, and (c) autopilot-measured approximate airspeed.
  • 9. Gliding. Landing flap setup over the airfield at suitable height. (a) Maintain straight and level into wind, (b) autopilot-measured average descent rate, and (c) autopilot-measured approximate airspeed.
  • 10. Steep turns. Clean setup. At safe height and suitable maneuvering speed. (a) Autopilot airspeed measured, (b) maximum angle of bank achievable at constant height level to the left at approximate autopilot airspeed and approximate autopilot measured throttle position, and (c) maximum angle of bank achievable at constant height level to the right at approximate autopilot airspeed and approximate autopilot measured throttle position.
  • 11. Steep turns. Take-off flaps. At safe height and suitable maneuvering speed. (a) Autopilot airspeed measured, (b) maximum angle of bank achievable at constant height level to the left at approximate autopilot airspeed and approximate autopilot measured throttle position, and (c) maximum angle of bank achievable at constant height level to the right at approximate autopilot airspeed and approximate autopilot measured throttle position.
  • 12. Steep turns. Landing flaps. At safe height and suitable maneuvering speed. (a) Autopilot airspeed measured, (b) maximum angle of bank achievable at constant height level to the left at approximate autopilot airspeed and approximate autopilot measured throttle position, and (c) maximum angle of bank achievable at constant height level to the right at approximate autopilot airspeed and approximate autopilot measured throttle position.
  • 13. Stalling clean. Climb to height then maintain straight and level. (a) Autopilot height measured and (b) idle power stall into wind - stall speed and height loss.
  • 14. Stalling clean climb. Climb to height. (a) Full power stall into wind - stall speed and height loss.
  • 15. Stalling take-off flaps. Climb to height then maintain straight and level. (a) Autopilot height measured and (b) idle power stall into wind - stall speed and height loss.
  • 16. Stalling landing flaps. Climb to height then maintain straight and level. (a) Autopilot height measured and (b) idle power stall into wind - stall speed and height loss.
  • 17. Max. level speed. Climb to height away from personnel. Increase airspeed incrementally. Maximum speed measured by autopilot.
  • 18. With aircraft in take-off configuration with flaps at specified angle, measure take-off run. Flaps to zero immediately after takeoff. (a) Take-off run measured, (b) autopilot average climb rate recorded within the first 5 s after take-off, and (c) aircraft climb average airspeed measured by autopilot.
  • 19. If possible, take off with zero flap. Measure take-off run. (a) Take-off run measured to be,
  • (b) autopilot average climb rate recorded within the first 5 s after takeoff, and (c) aircraft climb average airspeed measured by autopilot.
  • 20. Landing with full flap setting. (a) Flap position at specified angle, (b) approach speed autopilot approximate average, and (c) measure landing run - landing touchdown to stopped recorded.
  • 21. Landing with take-off flap setting. (a) Flap position at specified angle, (b) approach speed autopilot approximate average, and (c) measure landing run - landing touchdown to stopped recorded.
  • 22. Landing with zero flap (a) Approach speed autopilot approximate average and (b) measure landing run - landing touchdown to stopped recorded.

Compare the predicted results with the theoretical. Are there discrepancies? Given the above

results, is it safe to continue to next flight test?

 
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