What happened
The pilot conducted a preflight inspection of the aircraft and determined that the engine contained approximately 10 quarts of oil. Shortly after takeoff, while climbing through an altitude of about 1,000 feet mean sea level, the propeller revolutions per minute began to increase toward the redline limit. Recognizing the anomaly, the pilot reduced power and initiated an emergency landing procedure.
During a turn back toward the airport, the engine ceased operating entirely. The aircraft subsequently collided with trees and crashed while the pilot was attempting to land in an open field located approximately 4 miles from the airport.
The investigation
A post-crash examination of the wreckage revealed a ruptured oil hose, part number 63901-26, which connected the oil pump to the oil cooler. Investigation into the maintenance history showed that this specific hose had a designated life expectancy of 8 years and was manufactured in 1974. No records were found to indicate that the hose had been replaced since its original installation on the engine.
Findings
The primary factor contributing to the accident was the fuel exhaustion equivalent of oil loss due to the ruptured hose. The failure of the oil system led directly to engine stoppage during a critical phase of flight, preventing a safe landing and resulting in the collision with terrain.