Aviation Accident Final Report - National Transportation Safety Board: https://app.ntsb.gov/pdf
Docket And Docket Items - National Transportation Safety Board: https://dms.ntsb.gov/pubdms
Aviation Accident Data Summary - National Transportation Safety Board: https://app.ntsb.gov/pdf
Aviation Accident Factual Report - National Transportation Safety Board: http://app.ntsb.gov/pdf
FLIGHT SAFETY ALASKA INC: http://registry.faa.govN52950
FAA Flight Standards District Office: FAA Anchorage FSDO-03
NTSB Identification: GAA16CA487
14 CFR Part 91: General Aviation
Accident occurred Thursday, September 01, 2016 in Anchorage, AK
Probable Cause Approval Date: 01/18/2017
Aircraft: CESSNA 172, registration: N52950
Injuries: 2 Uninjured.
NTSB investigators used data provided by various entities, including, but not limited to, the Federal Aviation Administration and/or the operator and did not travel in support of this investigation to prepare this aircraft accident report.
The flight instructor reported that during taxi the airplane started to lean to the right, so he looked out of his window to see if the right tire was flat. He further reported that “the ramp was opening up into a 2 foot wide dark black hole” underneath the right main landing gear. The flight instructor and student pilot egressed from the airplane without further incident.
A postaccident examination revealed substantial damage to the empennage.
The flight instructor reported no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.
Photographs provided by Federal Aviation Administration showed that the right main landing gear had broken through the pavement into a sink hole underneath.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The airplane’s encounter with a developing sink hole during taxi on the ramp area.