LAX00FA209 · Cessna 152

While on base leg turning to final approach at the desert airport, the instructional flight was authorized by the air traffic control tower to perform s-turns for spacing due to another aircraft stopped in position on the runway and starting the takeoff roll. Witnesses observed the aircraft's wings rock steeply right and left and then the aircraft dove nose-first to the ground from about 250 feet agl. The recently certificated flight instructor had worked as an instructor for about 1 month and had 363 total flight hours. The flight was the student's first fixed-wing aircraft instructional flight, although he had about 60 hours experience in helicopters and the foreign equivalent of a private pilot certificate. Witnesses said that surface wind varies greatly in the area near the accident site. Two witnesses, one located 1/2 block south of the accident site and the other located two blocks east of the accident site, reported the surface wind was calm. A third witness, located two blocks north of the accident site, reported the wind was blowing about 40 knots. This third witness reported that when she arrived at the accident site, soon after it happened, and got out of her car, the wind blew her hat off and across the street. Ten minutes later the wind stopped and it became completely still. At the airport, about 1 mile southeast of the accident location, the surface wind remained less than 12 knots in the period from 2 hours before the accident to about 2 hours after it. Several pilots reported that wind shear is common in the area due to terrain induced eddies from nearby mountains. The airport did not have a low-level wind shear alert system. One witness reported the engine was 'sputtering' and another said it was silent; however, at the accident site the propeller exhibited deep leading edge damage, torsional twisting, and chordwise striations on the front face. No mechanical anomalies were found.

Verbatim NTSB analysis and probable cause from the NTSB dataset