Accident Overview
On April 12, 2014, at 1100 central daylight time, an Ercoupe 415-C, registration N2788H, was substantially damaged during a forced landing near Tenkiller Airport (44M) in Cookson, Oklahoma. The aircraft had just departed on a personal flight destined for a private airstrip in Etna, Arkansas, under visual meteorological conditions and in accordance with 14 Code of Federal Regulations Part 91. No flight plan was filed. Both the pilot and a pilot-rated passenger sustained serious injuries. There was no post-impact fire.
Pilot and Passenger Statements
The pilot-rated passenger reported that the first takeoff attempt was aborted due to a loss of engine power. After taxiing back to the departure end of the runway, they performed several full and partial power runs to clear the engine, which then seemed to perform well. During the subsequent takeoff, shortly after becoming airborne, the engine began losing power again. The pilot initiated a left turn back toward the runway but was unable to maintain altitude, resulting in a landing in wooded terrain.
Witness Account
A witness, who was a friend of the pilot, provided a similar account and added that the day before the accident, the pilot experienced a rough running engine on takeoff and landed quickly. The pilot could not duplicate the problem on the ground but noted that the header tank had overflowed. Upon opening the cowling, they saw that a large amount of fuel had evaporated and residual fuel stains were present around the carburetor. The witness then performed several high-speed taxi runs with no engine issues, followed by two full-stop landings. On the second landing, the header tank overflowed again. The pilot consulted the airplane's manual, which suggested a loose gasket in the gas cap as a possible cause, and tightened it. The next day, the witness asked if tightening the gasket had resolved the problem, and the pilot said it did.
Postaccident Examination
After the accident, examination of the wreckage revealed that all fuel tanks were breached. A small amount of fuel was found in the header tank and gascolator. The carburetor inlet fitting was broken due to impact, and the carburetor bowl contained no fuel. The mixture control was disconnected from the carburetor and was not safety-wired in the full-rich position. The top spark plugs were removed; No. 1 and No. 3 plugs were black. Manual rotation of the engine via the propeller established valve train continuity on each cylinder. Inside the cockpit, the primer was found unlocked and partially pulled out, and fuel was present in the primer line leading to the carburetor.
Background Information
The aircraft's last annual inspection was completed on February 1, 2014, at an airframe total time of 2,235 hours. It had accrued 15 hours since that inspection. The pilot held a private pilot certificate for airplane single-engine land, with a last FAA third class medical certificate issued in November 2008 and a last biennial flight review in November 2009. The pilot reported 850 total flight hours, of which 300 were in the same make and model. The pilot-rated passenger also held a private pilot certificate for airplane single-engine land, with a last FAA third class medical issued in May 1979, and reported 500 total flight hours, including 30 hours in the same make and model.