Accident Overview
On July 22, 2008, at approximately 1725 mountain daylight time, a Cessna 172M single-engine airplane, registration N7672, experienced a partial loss of engine power during the initial climb after takeoff from Skypark Airport (BTF) in Bountiful, Utah. The aircraft was operated by G&B Aircraft Management of Woods Cross, Utah, under Part 91 of the Federal Aviation Regulations. The certified flight instructor (CFI) and student pilot on board sustained minor injuries, while the airplane incurred substantial damage to its fuselage and left wing. Visual meteorological conditions prevailed, and no flight plan was filed for the local instructional flight.
Flight History
According to the CFI, the accident flight was the first flight of the day for the airplane. During the pre-takeoff engine run-up, the student pilot leaned the mixture for altitude per normal procedures. The student then taxied to the active runway and initiated the takeoff. As the airplane climbed through approximately 100 feet above ground level, the climb performance degraded and the engine partially lost power. The CFI immediately moved the mixture control to full rich, checked the carburetor heat, and confirmed the throttle was fully forward, but observed no improvement in climb rate. He then assumed control and executed a forced landing to an open field beyond the departure end of the runway. During the landing roll, the airplane's wheels sank into mud, causing it to nose over and come to rest inverted.
Post-Accident Examination
A Federal Aviation Administration (FAA) inspector examined the accident site and found the airplane inverted in a field about 1/4 mile north of Skypark Airport. Both left and right wing fuel tanks were full of 100-low lead aviation fuel. An NTSB investigator subsequently examined the Lycoming O-320-E2D engine, serial number L-22287-27A, and found no anomalies that would have precluded normal operation and power production. The airframe fuel system also exhibited no anomalies.