Incident Overview
A Certified Flight Instructor (CFI) reported that during pre-takeoff checks, the left and right magnetos functioned normally, but the engine ran rough. The CFI applied carburetor heat for a period, after which the engine smoothed out. The aircraft then taxied to runway 05 for departure.
Takeoff and Climb
During the takeoff roll, the engine continued to run rough, and the stall warning horn was heard. The CFI stated he intended to abort the takeoff, but the airplane began to lift off, and he reached a point of no return. As the climb continued, the engine lost power, and the stall warning horn became louder. The pilot immediately pulled the carburetor heat lever, and the engine rpm dropped.
Forced Landing
The pilot executed a forced landing in a field north of the airport. During the landing, the nose wheel became stuck in mud, causing the airplane to flip over and come to rest inverted. The pilot did not submit an NTSB Form 6120.1 pilot/operator report as of the time of the initial report.
Post-Accident Examination
An FAA inspector examined the airplane and found substantial damage to the vertical stabilizer, as well as buckling of the cockpit and fuselage. The post-accident examination revealed no mechanical or engine problems.