Event Summary
On October 27, 2019, at about 1600 central daylight time, a Piper J3C-65, registration N7009H, was substantially damaged during an accident near Grand Bay, Alabama. The airline transport pilot and a passenger were not injured. The flight was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
Sequence of Events
According to the pilot, a preflight inspection and engine run-up revealed no anomalies. During the run-up, he checked the carburetor heat and observed a 50-rpm decrease in engine power. Due to the short taxi time, he allowed the engine to warm up for about 5 minutes before initiating takeoff.
When the airplane reached about 40 ft above ground level, it "seemed to quit climbing" and the engine rpm began decreasing. The pilot pushed the throttle full forward, verified the carburetor heat was off and the fuel shutoff valve was on. He noted that the engine was not running rough, nor was it spitting or sputtering. Realizing the airplane would be unable to clear trees and powerlines ahead, he aborted the takeoff and slipped the airplane to lose altitude. The airplane touched down about 100 ft before the end of the runway and was unable to stop before going off the end. It continued through a wooden fence and came to rest on the other side.
Postaccident Examination
A Federal Aviation Administration airworthiness inspector performed a postaccident examination of the engine. Impact damage to the induction manifold assembly, propeller, and both main landing gear precluded an operational test of the engine. The inspector had limited tools available and the resting position of the engine prevented 360° rotation of the propeller. Nonetheless, the inspector reported no discrepancies with the valve train, air induction, exhaust, and fuel supply system components. The carburetor heat cable was intact and connected but could not be operationally tested due to impact damage. Engine oil quantity was approximately 4 quarts (normal capacity). The inspector did not remove the spark plugs, check magneto timing, or verify their functionality. A sufficient quantity of fuel was noted in the fuel tank, and a check of the fuel strainer revealed no contaminants.
Weather Conditions
At 1556, the weather reported at Mobile Regional Airport (MOB), about 10 miles northeast of the accident site, included a temperature of 22°C (72°F) and a dewpoint of 13°C (55°F). The calculated relative humidity at these values was about 58 percent. Review of the icing probability chart contained in Federal Aviation Administration Special Airworthiness Information Bulletin CE-09-35 indicated that the atmospheric conditions at the time of the accident were "conducive to serious icing at glide [idle] power."