Accident Overview
During the initial climb after takeoff, at approximately 150 feet above ground level (AGL), the aircraft experienced a loss of engine power. The power loss occurred shortly after the pilot turned off the fuel boost pump. The pilot executed a forced landing on a nearby interstate highway. To avoid striking vehicles on the highway, the pilot delayed the landing, which subsequently resulted in a hard landing.
Investigation Findings
Post-accident examination included an engine test run, which revealed no mechanical problems. The aircraft had been fueled with 87 octane automobile gasoline. According to Federal Aviation Administration (FAA) records, the airplane was not equipped with a Supplemental Type Certificate (STC) authorizing operation on auto gas. Additionally, Piper Mandatory Service Bulletin #855, dated January 14, 1987, explicitly prohibits the use of auto fuel in Piper aircraft.
Environmental Conditions
The ambient temperature at the time of the accident was approximately 90 degrees Fahrenheit. The airport elevation is 920 feet above mean sea level (MSL). The density altitude at the airport was calculated to be approximately 3,200 feet.
Suspected Cause
The suspected cause of the engine power loss was fuel vapor lock.