What happened
The pilot conducted two separate attempts to initiate a takeoff roll. During the first attempt, no specific mechanical issues were noted in the immediate narrative, though a witness later indicated engine irregularities occurred during both efforts. On the second takeoff attempt, the aircraft successfully lifted off the ground to an altitude of approximately 30 feet.
Shortly after becoming airborne, the engine experienced a significant loss of rotational speed, dropping from 2450 RPM to 1700 RPM. Recognizing the critical failure, the pilot aborted the takeoff immediately. The aircraft began to porpoise vertically three times as it descended back toward the runway surface. Unable to maintain control or stop within the remaining pavement, the aircraft continued off the end of the runway and came to rest in an adjacent bay.
A witness on the ground observed that the engine was cutting out during both takeoff attempts, suggesting a persistent mechanical issue prior to the final lift-off.