Primary finding
Probable cause
A loose fuel line fitting, and fuel starvation. Factors include an intentional wheels up forced landing, and soft rough/uneven terrain.
Investigator assessment
Analysis narrative
After experiencing a complete loss of engine power, the pilot attempted a forced gear-up landing on soft rough terrain. After touchdown the aircraft sustained substantial damage. An FAA inspector later found that a fuel line-to-engine fitting nut, which had been on the aircraft for over 85 hours, had come loose, resulting in fuel starvation.
Source record
Factual narrative
On December 31, 1993, approximately 1400 mountain standard time (MST), a Swiss registered Glasair I RG experimental aircraft, HBYDJ, impacted the terrain during a forced landing near Ogden, Utah. The private pilot, who was the sole occupant, was not injured, but the aircraft sustained substantial damage. The pilot, who was on a local pleasure flight, departed Ogden-Hinckley Municipal Airport about 20 minutes earlier. The pilot had not filed a flight plan, and there was no report of an ELT activation. According to the pilot, the engine lost power, and he attempted a forced landing on rough soft terrain. During the emergency descent, he made the decision to land with the gear up in an attempt to minimize the damage to the aircraft. An FAA inspector who responded to the accident found that a stainless steel nut on the fuel line-to-engine fitting had come loose, resulting in an interruption in the fuel flow to the engine. According to the pilot/manufacturer, the nut that came loose had been used to hold the fuel line to the engine for over 85 hours of powerplant operation. -