NTSB Identification: ANC01FA100.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Accident occurred Monday, August 06, 2001 in COOPER LANDING, AK
Probable Cause Approval Date: 07/15/2002
Aircraft: Cessna 172S, registration: N813SP
Injuries: 2 Serious,2 Uninjured.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
The private certificated pilot was on a personal sightseeing flight in a rental airplane. The pilot had limited experience in the airplane that was equipped with an intergrated flight/nav/autopilot system. During cruise flight, the airplane suddenly pitched upward. The pilot pushed forward on the control yoke, and noticed the trim wheel moving in a nose up direction. She used the manual trim wheel to trim the airplane nose down, but the airplane still pitched upward. The pilot began to exert forward pressure on the control yoke to keep the airplane from climbing, and asked her front seat passenger to help push forward on the control yoke. The pilot made a "mayday" call and decided to make an emergency landing at a 2,200 feet gravel surface airport. The pilot said she turned onto about a one mile final approach, but said she was either going too fast, or the runway was too short. The airplane touched down about mid-length on the runway and bounced several times. The pilot saw the end of the runway approaching, and added full throttle to begin a go-around. The airplane collided with trees at the departure end the runway. The pilot said she did not know if the autopilot was on or off, but she did not consciously select or use the autopilot, and did not even know if the airplane was equipped with electric trim. The pilot said she remembered seeing 7000 displayed in a box located above the transponder (the autopilot computer). The pilot said she used the radio transmit button on the left side of the pilot's control yoke, but did not use any other switches on the yoke. The pilot said her front seat passenger is not a pilot, and did not touch any items on the control panel. The autopilot was installed on the right side of the instrument panel. The pilot did not receive any instruction from the operator, or from her flight instructor about the autopilot system, and the pilot did not familiarize herself with the autopilot system. The pilot's flight instructor reported that during a previous training flight with another student, he discovered the autopilot system was on, even though he did not turn it on. Postaccident testing of the autopilot system did not reveal any malfunction.
The National Transportation Safety Board determines the probable cause(s) of this accident to be: The pilot's inadequate remedial action to disconnect the autopilot during an uncommanded altitude deviation while in cruise flight. Factors in the accident were activation of the autopilot; the pilot's lack of familiarity with the airplane's autopilot system; her failure to attain the proper touchdown point during an emergency landing, and delayed go-around resulting in an overrun and collision with trees; the operator's insufficient training standards for the airplane, and the pilot's flight instructor's failure to provide adequate upgrade/transition training in the airplane. Full narrative available
Index for Aug2001 | Index of months