Accident Overview
On November 7, 2009, at 1700 mountain standard time, a Piper PA-32R-300, registration N2165M, experienced a partial loss of engine power while in cruise flight. The pilot made an emergency landing on a highway approximately 32 miles northwest of Tucson International Airport (TUS), Tucson, Arizona. The owner/pilot operated the airplane under 14 Code of Federal Regulations Part 91 as a personal flight. The private pilot and one passenger were not injured. The airplane sustained structural damage to the fuselage after departing the highway and impacting a road sign and cacti before coming to rest upright. Visual meteorological conditions prevailed for the local area flight that departed Phoenix-Mesa Gateway Airport (IWA), Phoenix, Arizona, at 1616. No flight plan had been filed.
Pilot's Account
According to the pilot's written statement, he had been cleared direct to TUS via GPS at 6,500 feet mean sea level (msl). About 35 miles northwest of TUS, he started a descent to 4,500 feet msl. As the airplane passed through 5,000 feet, he configured the manifold pressure and rpm (24/2,400) per the airplane's pilot operating handbook (POH) for 4,000 feet at 75 percent power. Shortly thereafter, he felt the airplane 'lurch,' as if the engine had lost rpm. He increased engine power, fuel mixture, and moved the propeller to the FULL in position to attempt to regain power. The pilot stated that the engine continued to run and the propeller was still spinning, but it did not produce enough power to hold altitude; he noted a 500-foot-per-minute descent that he could not arrest. The pilot radioed TUS to report a partial engine failure and his position. TUS tower personnel gave him vectors to a closer airport; however, as he turned toward the airport, the airplane lost altitude too quickly and he knew it would not make the airport. The pilot stated that there was a road below and he attempted to land on it. He believes that about 20 feet above the ground, the engine quit, and the airplane landed hard. Upon touchdown, he heard a 'thud' and ascertained that the airplane had left the roadway onto the adjacent desert floor. After the accident, the pilot reported that the airplane struck a road sign.
Engine Inspection
An engine inspection was performed by investigators from the National Transportation Safety Board (NTSB) and Lycoming Engines. Under supervision, the cowling was removed. There were no obvious signs of a mechanical failure. All fuel lines were secure, and no fluid leaks were observed. The magnetos were secure and tight on their respective mounting pads. Manual rotation of the propeller produced thumb compression in all six cylinders. The servo plug remained in place and was secured by safety wire. No mechanical anomalies were noted that would have precluded normal operation.