What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) While enroute to home base, pilot observed an "engine" light followed by yaw. Entered autorotation, turned into wind. Deployed floats after below 75 KTS. Successful autorotation to water. Two mayday calls, rotor stopped with rotor brake. Passenger deployed raft, both exit aircraft. Picked up by boat. Aircraft rolled over before successful recovery. NTSB designated as incident due to no damage after successful autorotation. Aircraft rolled and submerged before recovery. Engine teardown and subsequent testing showed possible failure of oil check valve poppet o-ring part number 9794420060. Engine certification follow-up for corrective actions.
As the FAA filed it
(-23) WHILE ENROUTE TO HOME BASE, PILOT OBSERVED AN "ENGINE" LIGHT FOLLOWED BY YAW. ENTERED AUTOROTATION, TURNED INTO WIND. DEPLOYED FLOATS AFTER BELOW 75 KTS. SUCCESSFUL AUTOROTATION TO WATER. TWO MAYDAY CALLS, ROTOR STOPPED WITH ROTOR BRAKE. PASSENGER DEPLOYED RAFT, BOTH EXIT AIRCRAFT. PICKED UP BY BOAT. AIRCRAFT ROLLED OVER BEFORE SUCCESSFUL RECOVERY. NTSB DESIGNATED AS INCIDENT DUE TO NO DAMAGE AFTER SUCCESSFUL AUTOROTATION. AIRCRAFT ROLLED AND SUBMERGED BEFORE RECOVERY. ENGINE TEARDOWN AND SUBSEQUENT TESTING SHOWED POSSIBLE FAILURE OF OIL CHECK VALVE POPPET O-RING PART NUMBER 9794420060. ENGINE CERTIFICATION FOLLOW-UP FOR CORRECTIVE ACTIONS.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.