SEA99LA084 · Cessna 172P

After landing to the east during a simulated engine-out landing on the turf airstrip, the student was instructed to make a takeoff to the west using soft field techniques. Because the student had never performed an actual or simulated soft field takeoff before, the instructor explained the procedures to her while the aircraft idled at the east end of the runway. The student then initiated the takeoff to the west. During the takeoff roll, the airspeed stabilized around 45 MPH, and the instructor advised the student that as soon as the aircraft lifted off it would accelerate. After liftoff, the student climbed out at a rate that caused the airspeed to remain at 45 MPH, and after passing tree-top level about half way down the 2,640 foot airstrip, the aircraft stopped climbing. At that point the instructor took over and lowered the nose in an attempt to gain airspeed. In order to get the aircraft to accelerate, the instructor had to allow it to drop back toward the runway surface. As it neared the surface, the instructor became unsure whether the aircraft would clear the trees at the west end of the airstrip. He therefore aborted the takeoff and attempted to land on the remaining runway. During that attempt, the aircraft dropped in from about 20 feet above the surface, and after the nose gear bent back, the nose dug into the soft terrain and the aircraft flipped over on its back.

Verbatim NTSB analysis and probable cause from the NTSB dataset