On June 16, 2005, a Piper PA-28R-200 (registration N5229T) was involved in an aviation accident near Happy Jack, AZ. Investigators recorded the probable cause as: The fracture/separation of an engine intake valve during cruise flight, which resulted in a partial loss of engine power and a forced landing. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A pilot executed a forced landing on a rough dirt road after experiencing a partial loss of engine power during cruise flight at 10,500 feet. The aircraft sustained wing damage. Post-incident examination found an intake leak on cylinder no. 3.
Incident
The airplane was in cruise flight at approximately 10,500 feet mean sea level when it began to slowly lose altitude. The pilot attempted to increase engine power to arrest the descent, but these efforts failed. The pilot determined that the engine was capable of producing only partial power. To avoid an uncontrolled descent into terrain, the pilot landed on a rough dirt road. During the landing, the wings were damaged.
Examination
A subsequent examination of the engine revealed an intake leak on cylinder number 3. A piece of the intake valve was missing, and the edges of the fracture surface were jagged.