Piper PA 32-300 N5222S accident near Lancaster, Ohio

Probable cause

Fuel starvation due to the deterioration of the fuel selector valve, which allowed fuel to be fed from only the right tip tank. Contributing to the accident was the inadequate annual inspection, which failed to detect the deteriorated valve.

NTSB analysis

The pilot and pilot-rated passenger were conducting night touch-and-go landings and were in the traffic pattern for the second landing when the engine experienced a partial loss of power. The pilot advanced the throttle lever to increase the engine rpm, but the engine did not respond. The pilot moved the throttle lever, mixture control, and fuel selector and turned on the fuel pump in an attempt to troubleshoot the loss of power. Unable to restore engine power, the pilot made an emergency landing in a field. A postaccident examination revealed that the fuel selector valve was in the OFF position. The right tip fuel tank did not contain any fuel. The other three fuel tanks were mostly full of fuel.

Federal Aviation Administration Airworthiness Directive (AD) 77-12-01, applicable to the accident airplane, was issued on June 10, 1977, to prevent a fuel system malfunction and a possible power interruption. AD 77-12-01 requires regular inspection of the fuel selector valve; it was most recently completed during the annual inspection, about 5 months before the accident, and no anomalies were noted. A postaccident engine run revealed that the engine operated with no anomalies. The fuel selector valve was obviously worn and degraded to the point that it would not control the fuel flow. The detents were very worn and fuel continued to flow through the selector valve even when between detents and in the OFF position. Thus, the loss of engine power was likely a result of the deteriorated fuel selector valve, which allowed fuel to feed only from the right tip tank until it was exhausted. It is also likely that the deterioration of the fuel selector valve was overlooked during the last annual inspection.

Text from the NTSB. Open the NTSB docket for CEN14LA233 for the full record.