NTSB Factual Report

On October 24, 2013, about 1000 Pacific daylight time, a Piper PA-28-180, N30865, was substantially damaged when it impacted trees and terrain during a forced landing following a loss of engine power near Big Creek, California. The private pilot, the sole occupant onboard, was seriously injured. The airplane was owned by the pilot and another individual, and it was being operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91. No flight plan had been filed for the personal cross-country flight. The airplane had departed Bishop, California, approximately 1 hour before the accident; its planned destination was Fresno, California. Visual meteorological conditions prevailed in the vicinity of the accident site.

According to the Federal Aviation Administration (FAA), the pilot reported to an air traffic controller that the airplane's engine lost oil pressure and then lost power. The pilot performed a forced landing into trees at an elevation of about 8,200 feet in the mountainous terrain of the Sierra National Forest. Examination of photographs taken at the accident site by recovery personnel revealed that the airplane's wings, fuselage, and empennage were bent and wrinkled.

After the airplane was recovered to the facilities of Plain Parts in Pleasant Grove, California, it was examined under the supervision of a National Transportation Safety Board (NTSB) investigator on December 5, 2013. The examination revealed that there was engine oil coating the left rear side of the engine and extending down the left side of the fuselage. The source of the oil was found to be a fractured fitting at the oil pressure gage/sending unit port located on the left side of the engine's accessory case cover. An oil pressure sending unit, which appeared to be new, had been installed at this location, and the sending unit was found dangling by its electrical wiring harness. The sending unit and attached fittings measured about 2.5 inches in length, and the sending unit was not supported in any fashion. The engine case exhibited a bulging signature between the number 2 and number 4 cylinders consistent with an internal mechanical malfunction due to oil starvation. No further internal examination of the engine was performed.

It was noted during the examination that the engine had been modified by the installation of an electronic fuel injection and ignition system manufactured by Electronic Fuel Injection and Ignition (EFII) of Upland, California. According to the company's website, www.flyefii.com, its systems are intended for use on experimental category aircraft.

The most recent maintenance entry in the engine's maintenance logbook was made on July 10, 2013, by the co-owner of the airplane (who was not an FAA-certified mechanic) at a recording tachometer time of 3,446.01 hours. The logbook entry for this date stated, "annual insp. completed, oil and filter, replaced all cylinders and pistons with first run Lycoming O/H, EFII electronic ignition." There was no record in the logbook of the installation of a new oil pressure sending unit.

During a telephone interview conducted by the NTSB investigator-in-charge, the co-owner reported that the pilot (who also was not an FAA-certified mechanic) told him that he had installed the oil pressure sending unit just before the accident flight.

NTSB Probable Cause

The loss of engine power due to the improper installation of an oil pressure sending unit by the pilot, who was not a certificated mechanic, which resulted in a forced landing in mountainous terrain.