Incident Overview
On August 23, 2012, about 0905 eastern daylight time, a Piper PA-32R-301T, registration N362DM, experienced a loss of engine oil pressure during flight and subsequently made a forced landing on the median of Interstate 75 near Tampa, Florida. The airplane sustained substantial damage. The commercial pilot and two passengers were not injured. Visual meteorological conditions prevailed, and an instrument flight rules flight plan was filed for the personal flight under Title 14 Code of Federal Regulations Part 91. The flight originated from Peter O Knight Airport (TPF) in Tampa at 0900.
Pilot Actions
During preflight inspection, the pilot noted the engine required two quarts of oil, which were added. The ground run-up and initial climb were uneventful. At approximately 4,000 feet mean sea level, the low voltage warning light illuminated. The pilot cycled the alternator, but the light remained on. He communicated with air traffic control and was vectored back to TPF. During the return, a film of oil accumulated on the windshield, initially a fine spray that quickly covered the pilot side. A stream of oil was observed coming from the front of the engine cowling. The pilot informed the controller of the oil loss and uncertainty about reaching TPF as engine oil pressure dropped to zero. He declared an emergency and planned to land on a section of Interstate 75. The airplane was maneuvered to land on the median between north and southbound lanes. During the landing roll, the left wing struck a highway sign before the airplane came to a stop. All occupants exited on their own.
Post-Accident Examination
An FAA inspector examined the wreckage and found an eight-foot section of the outer left wing separated. Engine oil was leaking from the forward section of the engine. A postaccident engine examination revealed a noticeable cut on the lower left side of the propeller governor gasket. The lower left lock nut securing one of three control cable bracket tube ends and the propeller governor did not appear properly seated, though anti-tamper putty was present. The engine was serviced with six quarts of oil, the spark plugs removed, and the propeller governor cleaned of oil residue. When rotated with the starter, fresh oil immediately seeped from the gasket cut area. The bracket, governor, and gasket were removed for examination. The lower left corner of the gasket broke off during removal. Several cracks were observed extending to the lower section where the oil leak was concentrated. The control cable support bracket tube end at the leak location had its top section missing (broken off); the other two tube ends were intact.
Maintenance History
The airplane owner stated there was no history of engine discrepancies requiring removal of that control cable support bracket. However, he recalled that a few years prior, during an overnight stay, a maintenance facility corrected an engine oil leak. The mechanic on duty was not familiar with general aviation piston engines. A work order dated November 4, 2007, obtained by the FAA inspector, documented replacement of an oil temperature sensor gasket and repair of the breather tube, which corrected the leak. The engine accumulated about 650 operational hours since then before the accident. A review of the airplane’s maintenance logbooks by the FAA did not reveal documentation of the November 4, 2007 work, nor any entries accounting for removal of the control cable support bracket tube ends from the propeller governor attachment engine-mounted studs.