NTSB Factual Report

On September 28, 2010, at 1038 central daylight time, a Cessna 172RG, N5145U, registered to and operated by Spartan Aviation Industries, Inc., was destroyed when a fire broke out in the engine compartment while returning to the Richard Lloyd Jones, Jr., Airport (RVS), Tulsa, Oklahoma. The instructor pilot attempted a forced landing and impacted terrain 2 miles west of the airport. Visual meteorological conditions (VMC) prevailed at the time of the accident. The instructional flight was being conducted under the provisions of 14 Code of Federal Regulations (CFR) Part 91 without a flight plan. The flight instructor was seriously injured, and the certified flight instructor (CFI) candidate received minor injuries. The local flight originated from RVS approximately 0930.

According to the flight instructor's accident report, the landing gear was lowered only once during the flight when they practiced slow flight in the landing configuration. They returned to RVS and lowered the landing gear in preparation for landing. The instructor wrote, “Within seconds of lowering the gear, flames started pouring out from under the instrument panel and up the front of the panel. The carpet on the floor also caught fire quickly.” An emergency was declared, and then the radio failed. The mixture control was pulled to idle cutoff, but the fuel selector could not be turned off due to the flames. The cabin filled with smoke, the instruments became unreadable, and the pilots were having trouble breathing. The instructor opened his (left) door, causing the airplane to yaw to the left, and he used right rudder to compensate. The rudder pedals were “fully covered in flames.” The instructor’s right foot was on fire and his shoe was melting to his foot. The CFI candidate, who was in the right seat, was able to remove the instructor’s shoe but the instructor's calf was also on fire. In the ensuing forced landing, the instructor was able to avoid power lines but was unable to clear a fence. The airplane struck the fence and came ”to a stop suddenly.” Both occupants evacuated the airplane. The CFI candidate's report corroborated the instructor’s report.

According to the Federal Aviation Administration (FAA) inspector who responded to the accident site, he found evidence that the terminal lug on the hydraulic pump was improperly installed and had shorted. There was no evidence that the exposed lug had been properly covered. The inspector examined six other Cessna 172RG’s at the airport and found two airplanes had exposed terminal lugs, three airplanes had a rubber boot (part number MS25171-2S) installed to cover the lug, and only one airplane was equipped with the proper cover (part number S1807-1). The inspector also discovered that the installation procedures for the hydraulic power package did not specifically mention the cover. Only the Cessna 172RG Illustrated Parts Catalog depicted the correct and proper installation.

NTSB Probable Cause

A shorted terminal lug on the landing gear hydraulic pump which resulted in a cabin fire. Contributing to the accident was the lack of clear installation procedures for the hydraulic pump.