What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
A GPS failure during a maritime flares UAS training event triggered land mode, which resulted in steady descent and downwind drift of the multi-copter. The aircraft was tethered to an articulating and translating flatbed trailer (ship deck simulator). The operator is aft-facing from the back door of the tow vehicle.
The student operator’s initial joystick response to the GPS failure was correct. Then the aircraft veered off-course and out of sight. It impacted the surface, climbed above 100 feet AGL overturned and impacted a second time. Substantial damage resulted. No personnel injuries or fire was observed.
Root cause: a fatigued wire crimp failed, which cut power to the GPS receiver. Subsequent operator input caused loss of control and ground impact.
As the FAA filed it
A GPS FAILURE DURING A MARITIME FLARES UAS TRAINING EVENT TRIGGERED LAND MODE, WHICH RESULTED IN STEADY DESCENT AND DOWNWIND DRIFT OF THE MULTI-COPTER. THE AIRCRAFT WAS TETHERED TO AN ARTICULATING AND TRANSLATING FLATBED TRAILER (SHIP DECK SIMULATOR). THE OPERATOR IS AFT-FACING FROM THE BACK DOOR OF THE TOW VEHICLE.
THE STUDENT OPERATOR’S INITIAL JOYSTICK RESPONSE TO THE GPS FAILURE WAS CORRECT. THEN THE AIRCRAFT VEERED OFF-COURSE AND OUT OF SIGHT. IT IMPACTED THE SURFACE, CLIMBED ABOVE 100 FEET AGL OVERTURNED AND IMPACTED A SECOND TIME. SUBSTANTIAL DAMAGE RESULTED. NO PERSONNEL INJURIES OR FIRE WAS OBSERVED.
ROOT CAUSE: A FATIGUED WIRE CRIMP FAILED, WHICH CUT POWER TO THE GPS RECEIVER. SUBSEQUENT OPERATOR INPUT CAUSED LOSS OF CONTROL AND GROUND IMPACT.