What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
? A/c was performing research & development operations (91) from the Pendleton (kpdt) airport
? No injuries to any people
? Other than the a/c, no property damage
? The a/c was connected to shore power and began its boot up and initialization procedures per the drone flight manual (dfm) checklist
? 113.9 Seconds later, the red light (located on the nose of the a/c) turns off (green light on), at which time the drone is in the fixed-wing orientation on the cart facing 185 degrees. After the red light turned off, the crew began to manipulate the drone.
? Quote from drone flight manual: “the aircraft cannot be moved after power up in order to give time to the inertial navigation system (ins) to initialize correctly. During this time all software will boot, the red light will switch off after this process is complete (approximately two (2) minutes).”
? 113 To 157 seconds, the navigation system is attempting to initialize but is unable to because of excessive motion occurring. The physical movement of the drone to the pad, rotation to the vtol position, and removal from the cart occur and prevent proper initialization of navigation system
? 157 To 167 seconds, a stationary period occurs and the navigation system finishes initialization, but because of the error introduced by the rotation on the cart, the initialized heading is over 100° away from the expected 185° value.
? The dfm and pre-flight checklists include a step to verify that the heading displayed on the mission execution (mex) window matches the actual orientation of the drone as placed on the pad within 20 degrees. Drone log review indicates that the heading displayed on the mex window was ~80 degrees at the time in the process when the heading check should have been completed. It should have been noted by the operator that this check did not pass, and therefore the takeoff should not have proceeded.
O the displayed heading and the actual orientation of the drone on the pad has a limit of +/- 20°. In this case, the difference was approx. 100°
? 7 Seconds after takeoff, a health alert GPS caution (NAV-CA-001) populated during vertical ascent from takeoff on the ground control station (gcs)
? A/c departed intended flight path
? 32 Seconds after takeoff, health alert, flight critical warning: nav and sensing system estimated posvel horiz degraded (NAV-DT-002) populated on the gcs
? A/c initiated an urgent land contingency but was unable to execute due to a corruption of the navigation coordinates
? The a/c contacted the ground 59 seconds after takeoff and 930 meters from the takeoff pad
? A/c was flying at a heading of approx. 30 degrees and an airspeed of approx 24 meters per second (53.69 mph) when it contacted the ground
As the FAA filed it
? A/C WAS PERFORMING RESEARCH & DEVELOPMENT OPERATIONS (91) FROM THE PENDLETON (KPDT) AIRPORT
? NO INJURIES TO ANY PEOPLE
? OTHER THAN THE A/C, NO PROPERTY DAMAGE
? THE A/C WAS CONNECTED TO SHORE POWER AND BEGAN ITS BOOT UP AND INITIALIZATION PROCEDURES PER THE DRONE FLIGHT MANUAL (DFM) CHECKLIST
? 113.9 SECONDS LATER, THE RED LIGHT (LOCATED ON THE NOSE OF THE A/C) TURNS OFF (GREEN LIGHT ON), AT WHICH TIME THE DRONE IS IN THE FIXED-WING ORIENTATION ON THE CART FACING 185 DEGREES. AFTER THE RED LIGHT TURNED OFF, THE CREW BEGAN TO MANIPULATE THE DRONE.
? QUOTE FROM DRONE FLIGHT MANUAL: “THE AIRCRAFT CANNOT BE MOVED AFTER POWER UP IN ORDER TO GIVE TIME TO THE INERTIAL NAVIGATION SYSTEM (INS) TO INITIALIZE CORRECTLY. DURING THIS TIME ALL SOFTWARE WILL BOOT, THE RED LIGHT WILL SWITCH OFF AFTER THIS PROCESS IS COMPLETE (APPROXIMATELY TWO (2) MINUTES).”
? 113 TO 157 SECONDS, THE NAVIGATION SYSTEM IS ATTEMPTING TO INITIALIZE BUT IS UNABLE TO BECAUSE OF EXCESSIVE MOTION OCCURRING. THE PHYSICAL MOVEMENT OF THE DRONE TO THE PAD, ROTATION TO THE VTOL POSITION, AND REMOVAL FROM THE CART OCCUR AND PREVENT PROPER INITIALIZATION OF NAVIGATION SYSTEM
? 157 TO 167 SECONDS, A STATIONARY PERIOD OCCURS AND THE NAVIGATION SYSTEM FINISHES INITIALIZATION, BUT BECAUSE OF THE ERROR INTRODUCED BY THE ROTATION ON THE CART, THE INITIALIZED HEADING IS OVER 100° AWAY FROM THE EXPECTED 185° VALUE.
? THE DFM AND PRE-FLIGHT CHECKLISTS INCLUDE A STEP TO VERIFY THAT THE HEADING DISPLAYED ON THE MISSION EXECUTION (MEX) WINDOW MATCHES THE ACTUAL ORIENTATION OF THE DRONE AS PLACED ON THE PAD WITHIN 20 DEGREES. DRONE LOG REVIEW INDICATES THAT THE HEADING DISPLAYED ON THE MEX WINDOW WAS ~80 DEGREES AT THE TIME IN THE PROCESS WHEN THE HEADING CHECK SHOULD HAVE BEEN COMPLETED. IT SHOULD HAVE BEEN NOTED BY THE OPERATOR THAT THIS CHECK DID NOT PASS, AND THEREFORE THE TAKEOFF SHOULD NOT HAVE PROCEEDED.
O THE DISPLAYED HEADING AND THE ACTUAL ORIENTATION OF THE DRONE ON THE PAD HAS A LIMIT OF +/- 20°. IN THIS CASE, THE DIFFERENCE WAS APPROX. 100°
? 7 SECONDS AFTER TAKEOFF, A HEALTH ALERT GPS CAUTION (NAV-CA-001) POPULATED DURING VERTICAL ASCENT FROM TAKEOFF ON THE GROUND CONTROL STATION (GCS)
? A/C DEPARTED INTENDED FLIGHT PATH
? 32 SECONDS AFTER TAKEOFF, HEALTH ALERT, FLIGHT CRITICAL WARNING: NAV AND SENSING SYSTEM ESTIMATED POSVEL HORIZ DEGRADED (NAV-DT-002) POPULATED ON THE GCS
? A/C INITIATED AN URGENT LAND CONTINGENCY BUT WAS UNABLE TO EXECUTE DUE TO A CORRUPTION OF THE NAVIGATION COORDINATES
? THE A/C CONTACTED THE GROUND 59 SECONDS AFTER TAKEOFF AND 930 METERS FROM THE TAKEOFF PAD
? A/C WAS FLYING AT A HEADING OF APPROX. 30 DEGREES AND AN AIRSPEED OF APPROX 24 METERS PER SECOND (53.69 MPH) WHEN IT CONTACTED THE GROUND