Sequence of Events
A pilot was conducting touch and go landings on a 1,000-foot private grass airstrip bordered by trees at both ends. Prior to the operation, the pilot calculated takeoff performance, estimating a ground roll of 700 feet without obstacles and 1,200 feet to clear a 50-foot obstacle.
During the first landing, the aircraft touched down 200 feet from the runway threshold. The pilot then applied full power and initiated a takeoff without retracting the 40-degree flap setting. During the initial climb, the airplane's landing gear clipped a line of trees. The airplane subsequently collided with the ground nose-first and came to rest 500 feet beyond the end of the runway.
Aircraft Flight Manual Guidance
According to the 1967 Cessna 172H Airplane Flight Manual, flap settings of 30 to 40 degrees are not recommended at any time for takeoff. Additionally, the manual contains no performance data for takeoffs conducted with 40 degrees of flaps.
Pilot Performance Calculations
The pilot had determined that 700 feet of ground roll would be required for a takeoff without obstacles, and 1,200 feet for a 50-foot obstacle clearance. The reported touchdown point was 200 feet from the threshold, and the aircraft's final position was 500 feet off the end of the runway.