On May 6, 2014 about 2130 eastern daylight time, a Piper PA 32-300 airplane, N5222S, made an emergency landing in a field near Lancaster, Ohio. The private pilot and pilot rated passenger were not injured. The airplane sustained substantial damage. The airplane was registered to and operated by a private individual under the provision of 14 Code of Federal Regulations Part 91 as a personal flight. Night visual meteorological conditions prevailed at the time of the accident and no flight plan was filed. The local flight originated about 2120. The pilot reported that he was conducting touch-and-go landings and was flying in the traffic pattern for the second landing when the engine experienced a partial loss of power. The pilot attempted to adjust the throttle lever while turning base to final, but the engine did not respond. The pilot and passenger moved the throttle lever, mixture control, fuel selector and turned on the fuel pump in an attempt to restore the power. The engine power was unable to be restored so the pilot made an emergency landing in a field. A postaccident examination revealed that the throttle, fuel mixture, and propeller controls were found in the full forward position. The fuel selector valve was found in the OFF position. The right tip fuel tank did not contain any fuel. The other 3 fuel tanks (right main, left main, left tip) were mostly full of fuel. A postaccident engine run revealed that the engine operated with no anomalies. The fuel selector valve was worn and degraded to the point that it would not control the fuel flow. The detents were worn and fuel would continue to flow through the selector valve even when selected between detents and in the OFF position. On June 10, 1977, the Federal Aviation Administration issued Airworthiness Directive (AD) 77-12-01 PIPER AIRCRAFT CORPORATION: Amendment 39-2914, applicable to the accident airplane, "to prevent a fuel system malfunction and a possible power interruption." On December 5, 2013, during the most recent annual inspection, AD 77-12-01 was completed and no anomalies were noted.