Probable cause
The airplane’s encounter with a developing sink hole during taxi on the ramp area.
NTSB analysis
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.
Text from the NTSB. Open the NTSB docket for GAA16CA487 for the full record.
Event
- Date
- Sep 1, 2016
- Type
- Accident
- Place
- Anchorage, Alaska
- Nearest airport
- Merrill Field (MRI)
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
Cessna 172
- N-number
- N52950
- Category
- Airplane
- Year built
- 1981
- Damage
- Substantial
- Operating rule
- Part 91 (general aviation)
- Purpose of flight
- Instructional
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.