Cessna 172RG N6511V accident near Anoka, Minnesota

Probable cause

Failure of the left landing gear actuator for reasons that could not be determined because the actuator was not made available for examination.

NTSB analysis

The flight instructor and commercial-rated pilot receiving instruction departed the airport. When the commercial pilot retracted the landing gear, the pilots both heard a loud "clang" from the vicinity of the left main landing gear. The pilots lowered the landing gear; the right main gear extended but the left main gear did not extend. The pilots recycled the landing gear and then attempted the emergency gear extension procedure, which were both unsuccessful in lowering the left main gear. The pilots flew to the airport and the tower controller reported that the gear was partially extended. The instructor then attempted several maneuvers to get the gear to go down and lock, but these had no effect. When the pilots determined that they would not be able to lower the left main landing gear, the flight instructor performed an intentional gear-up landing. A postaccident examination of the airplane revealed a fractured left main landing gear actuator. Numerous attempts to obtain the broken actuator from the operator were unsuccessful, and a detailed examination of the actuator was not possible.

Text from the NTSB. Open the NTSB docket for CEN15LA309 for the full record.