The inquiry Scrutiny attributed Causation the blade fracture to metal fatigue , caused Causation by heavy vibration in the newly upgraded Cause_to_make_progress engines , which had been tested Testing only in the laboratory and not under representative flight conditions .

The subsequent crash investigation Scrutiny found Know that the incident Catastrophe had been caused Causation by fatigue failure and consequent disintegration of a rotor disc in the left Departing hand engine ( engine # 1 ) .

For some days prior to his death , Hendrix had been in poor health , in part from fatigue caused Causation by overwork , a chronic lack of sleep , and an assumed influenza-related illness .

It was determined that the accident Catastrophe was caused Causation by a fatigue crack in the main spar of the left wing that caused Causation the outer part of the left wing , outboard of the engine nacelle , to separate Forming_relationships from the remainder of the aircraft .

The expert panel investigating Research the accident believed this to be the first fatal aircraft accident Catastrophe anywhere in the world directly attributable to metal fatigue .

The accident Catastrophe and related matters were investigated Research by a Supreme Court judge who also found Know that the aircraft 's left wing failed in flight due to a fatigue crack .

The judge made Action five recommendations including one that a safe flying life should be fixed Resolve_problem for each metal aircraft registered in Australia to avoid further failures due to metal fatigue .

The British engineers ' incompetence and losses Earnings_and_losses to disease and fatigue forced Causation the commander to stop Process_end his offensive .

The NTSB investigation revealed Reveal_secret evidence of pre-existing metal fatigue , and determined Deciding the probable cause Causation of the incident to be related to an error in the manufacturing Manufacturing process for joining Becoming_a_member fuselage crown skin panels .

Eventually , the Marines ceased Process_end their pursuit when their commander was killed Killing and retreated Escaping back to their ship due to fatigue and heat exhaustion , with the Formosans dispersing Dispersal and retreating Escaping back into the jungle .

The inquest found Know that the accident was due Causation to metal fatigue of two bolts in the elevator system .