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Analysis of the motor failure indicates that the failure was caused was due to overheating of the motor from running at high power for a prolonged period of time. The flight-line team thereafter removed the wings to reduce weight and tried running a hover-test again to test the motor again. Unfortunately, the same problem occurred and the rear-right motor gave way. Through more investigation and research into motor specifications, it was concluded that the desired flight profile, as a fixed wing aircraft with vertical takeoff capability, was not achievable using the current motors in the given weather conditions, as these motors were intended to run at maximum current for three minutes at a time but we experienced failures far faster than the rated operating time. The team concluded it would be unsafe to transition without further validation of the aircraft performance.
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Over the course of Task 1 and Task 2, various faults were identified and noted for subsequent years' competitions. The most significant lesson learned from the competition tasks was to keep the drone design simple, test frequently, and to test often, in various test during different weather conditions. The original design of the aircraft was a VTOL fixed-wing hybrid which was optimized for controlled vertical landing on landing pads , as well as long-distance flying between waypoints. However, the drone’s weight of the drone was too high, causing the motors to have to work harder and overheat, preventing the drone from flying longer than three minutes. All of the testing for was greater than anticipated, and the motors were not able to generate enough thrust for greater than 3 minutes of quad flight. All testing of the aircraft was performed in the winter with very cold temperatures, so the overheating issues were never encountered by the team. Therefore a valuable lesson learned was to take into account the ambient temperature of the drone when conducting flight tests.
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