Accident Overview
On August 31, 2018, at about 1400 eastern daylight time, a Luscombe 8E airplane, registration N2305K, was substantially damaged during a forced landing near New Carlisle, Ohio. The pilot sustained serious injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Flight History
The pilot reported that the preflight inspection revealed no anomalies. He visually confirmed that the right wing fuel tank was full and the left tank was about half full. After starting the engine, he taxied to the runway and performed an engine runup, which showed no issues. He verified the proper operation of the carburetor heat control and observed no signs of carburetor ice.
During takeoff, the airplane became airborne about one-half to two-thirds down the 2,000-foot-long runway. After liftoff, the pilot noted reduced climb performance, and the engine began running rough at about 150 feet above ground level. He turned on the carburetor heat but then turned it off when the roughness seemed to increase. The engine then lost all power. The pilot turned right toward a nearby nursery and executed a forced landing. The airplane landed hard on uneven terrain, collapsing the main landing gear.
Post-Accident Examination
The airplane came to rest about half a mile west-northwest of the departure end of runway 27. Substantial damage occurred to the forward fuselage and right wing during the hard landing. Flight control continuity from the cockpit to all surfaces was confirmed. First responders reported a strong fuel smell and observed fuel leaking from the engine compartment. A mechanic from the airport later turned off the right fuel tank valve to stop the leak. The left fuel tank valve was found in the off position. The right and left fuel tanks contained about 5 gallons and 6.75 gallons of fuel, respectively. Fuel samples were blue, smelled of 100 low-lead aviation fuel, and had minor particulate contamination. The vented fuel tank caps showed no anomalies or obstructions. The fuel gascolator bowl shattered on impact. The engine remained attached to the firewall, but the carburetor separated from the crankcase. Engine control continuity was confirmed from the cockpit to the carburetor. Movement of the throttle arm discharged fuel from the accelerator pump into the carburetor venturi. The carburetor bowl was intact and contained uncontaminated fuel. The carburetor heat valve position could not be determined due to impact damage.
Internal inspection of the engine revealed continuity of the engine and valve train. When the crankshaft was rotated, compression and suction were noted on all cylinders. Compression measurements exceeded 70 psi for all four cylinders. Borescope inspection of each cylinder showed no evidence of mechanical failure of pistons or valves. Spark plugs indicated normal engine operation. Both magnetos produced spark when the crankshaft was rotated. The propeller remained attached; one blade was bent aft about midspan, and the other blade was straight with no rotational damage. No evidence of mechanical malfunction that would have precluded normal operation was found.
Carburetor Icing Conditions
According to a carburetor icing probability chart in FAA Special Airworthiness Information Bulletin CE-09-35, the recorded temperature and dew point around the time of the accident were conducive to carburetor icing at a descent engine power setting. The bulletin notes that ice formation in a fixed-pitch propeller aircraft's carburetor restricts induction airflow, causing decreased power output and a drop in engine rpm, possibly accompanied by engine roughness. It advises applying full carburetor heat immediately and notes that the engine may run rough briefly as ice melts.