What happened
The pilot initiated an emergency landing procedure following a complete loss of engine power. Prior to the catastrophic failure, the aircraft experienced approximately four distinct drops in manifold pressure, signaling underlying mechanical distress. Despite these warning signs and having opportunities to land at airports along the route short of the intended destination, the pilot elected to continue the flight.
The investigation
Post-accident examination revealed significant structural damage resulting from the landing gear collapsing upon impact. This collapse bent the engine mounts and damaged both wing spars. Further technical analysis determined that a 100-hour inspection had been completed just six days before the incident. During this maintenance, the mechanic apparently failed to ensure that the left crossover exhaust collection elbow tube was properly aligned and that its clamp was securely fastened.
Findings
The improper installation of the exhaust component allowed heat from exhaust gases to melt the lead from the 'P' lead ends. This molten material flowed into the condensers, causing both magnetos to short out and resulting in the total loss of power. The pilot's decision to continue flight despite manifold pressure fluctuations contributed to the severity of the outcome.