What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Airman failed to secure the latches which secure the left hand engine compartment door. Aircraft departed las airport on a 14 CFR part 135 air tour to the Grand Canyon. While enroute to the Canyon at approximately bonnelli bay, the engine compartment door flew up into the main rotor system causing substantial damage to the main rotor blades, and also destroyed the engine cowling door. The pilot made an emergency landing to a remote site and landed safely. Operator dispatched another helicopter with mechanic onboard. The pilot and mechanic elected to fly this aircraft from it's present location to boulder city airport.
As the FAA filed it
AIRMAN FAILED TO SECURE THE LATCHES WHICH SECURE THE LEFT HAND ENGINE COMPARTMENT DOOR. AIRCRAFT DEPARTED LAS AIRPORT ON A 14 CFR PART 135 AIR TOUR TO THE GRAND CANYON. WHILE ENROUTE TO THE CANYON AT APPROXIMATELY BONNELLI BAY, THE ENGINE COMPARTMENT DOOR FLEW UP INTO THE MAIN ROTOR SYSTEM CAUSING SUBSTANTIAL DAMAGE TO THE MAIN ROTOR BLADES, AND ALSO DESTROYED THE ENGINE COWLING DOOR. THE PILOT MADE AN EMERGENCY LANDING TO A REMOTE SITE AND LANDED SAFELY. OPERATOR DISPATCHED ANOTHER HELICOPTER WITH MECHANIC ONBOARD. THE PILOT AND MECHANIC ELECTED TO FLY THIS AIRCRAFT FROM IT'S PRESENT LOCATION TO BOULDER CITY AIRPORT.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.