As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AN UNCONTROLLED ACCELERATION WAS EXPERIENCED DURING THE STARTING PROCEDURE FOR MEDICAL RETRIEVAL MISSION. THE PILOT SHUTDOWN THE ENGINE AND NO ACCIDENCES WERE RECORDED. THE ON GROUND INVESTIGATION REVEALED THAT THE FCU COUPLING WAS FOUND DISENGAGED FROM FCU, PUSHED TOO FAR INTO FUEL PUMP CAUSING SPLINE TO DISENGAGE FROM FCU.