The causes
A94-0008
http://www.bfu.admin.ch/common/pdf/HB-XQA Prel. Report
A94-0009
http://www.bfu-web.de/berichte/98_cx010dfr.pdf Engine Failure due to fuel pump failure
A94-0010
http://www.ntsb.gov/NTSB/brief.asp?e...14X00605&key=1 Prel.Report
A94-0015
http://www.ntsb.gov/NTSB/brief.asp?e...30X01223&key=1 Corrosion fatigue within the blade retention bolt bushing(s) of the main rotor blade grip resulting in fatigue, cracking and ultimate separation of the upper grip plate. The separation of the upper blade grip plate led to a dynamic imbalance within the rotor system and the subsequent loss of all four rotor blades in flight.
A94-0017
http://www.ntsb.gov/NTSB/brief.asp?e...12X21608&key=1 The termination of power to the main rotor system as a result of the malfunction of the free-wheeling sprag clutch assembly, followed by the torsional overload separation of the engine adapter shaft. Factors include trees in the area where the emergency descent was attempted.
A94-0018
http://www.ntsb.gov/NTSB/brief.asp?e...12X19787&key=1 Accident in Austria: NTSB Brief: The pilot reportedly stated that after a loss of engine power, he jettisoned his external load and executed a forced landing. During the landing, the helicopter rolled onto its side, and the engine could still be heard running at a low RPM.
A94-0022
http://www.ntsb.gov/NTSB/brief.asp?e...11X09961&key=1 The pilot's inadvertent shutdown of the engine with the FUEL/OIL shutoff switch. Contributing to the accident were: the manufacturer's inadequate location and design of the FUEL/OIL shutoff switch; the FAA's inadequate determination of the type design's compliance with applicable airworthiness standards; and the helicopter's low altitude at the time of the power loss.
A94-0023
http://www.ntsb.gov/NTSB/brief.asp?e...11X09455&key=1 The pilot's failure to maintain control during autorotation, which resulted in an unleveled attitude touchdown, roll over, and collision with the ground.
More information about K-MAX here:
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