# Accident 20160901022949A: Cessna 172P, Anchorage, AK, September 1, 2016

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: September 1, 2016, 13:30 local time
- Place: Anchorage, AK
- Damage: Substantial damage
- Phase of flight: Taxi
- Operating rules: General operating rules (Part 91)
- Location: 61.2131° N, 149.8400° W: From the FAA
- Nearby events: https://openairdocs.org/map.md?lat=61.2131&lon=-149.8400&mi=10
- Aircraft: N52950, registered now (https://openairdocs.org/aircraft/N52950) (OpenAirDocs)
- Registry model: Cessna 172P (registry code 2072436, https://openairdocs.org/model/cessna-172p) (OpenAirDocs)
- Registry engine: Lycoming 0-320 series (registry code 41508, https://openairdocs.org/engine/lycoming-0-320-series) (OpenAirDocs)
- Reported make and model: CESSNA 172P
- People aboard: 2
- Fatal injuries: 0
- Other injuries: 0
- Pilot certificates: Commercial pilot, flight instructor
- Pilot flight hours: 955 total, 750 in this make and model, 200 in the last 90 days
- NTSB investigation: [NTSB GAA16CA487](https://openairdocs.org/ntsb/GAA16CA487) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/20160901022949A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

ON 1 SEP, 2016, MY STUDENT AND I PUT THE FLAPS UP IN N52950, WHILE SITTING ON A TAXIWAY NEAR TO ABEAM THE LAND AND SEA AVIATION FUEL POINT, GETTING READY TO TAXI. I FELT THE AIRCRAFT STARTING TO LEAN TO THE RIGHT AND IMMEDIATELY LOOKED OUT MY RIGHT WINDOW TO SEE IF IT WAS DUE TO A FLAT TIRE. TO MY SURPRISE, THE RAMP WAS OPENING UP INTO A 2 FT. WIDE DARK BLACK HOLE UNDERNEATH OUR RIGHT LANDING GEAR! I IMMEDIATELY YELLED, "EMERGENCY, EVACUATE!" I THEN IMMEDIATELY CUT THE MIXTURE TO PREVENT PROP/ENGINE DAMAGE, AS I ASSUMED THE AIRCRAFT  MAY CONTINUE TO SINK INTO THE RAMP, AND WE QUICKLY EVACUATED THE AIRCRAFT WITHOUT STOPPING TO GRAB ANYTHING! ONCE WE WERE OUT OF THE AIRCRAFT, THE PLANE STOPPED SINKING AND I WENT BACK TO TURN THE FUEL SELECTOR OFF, MASTER OFF, AND MAGS OFF. GOD WAS DEFINITELY LOOKING OUT FOR ME THAT DAY, AS THE SINKHOLE TURNED OUT TO BE A 18 FT. DEEP X 40 FT. WIDE CAVITY UNDERNEATH THE RAMP; HOWEVER, ALERTNESS AND QUICK REACTION DEFINITELY PLAYED A HUGE PART IN US GETTING OUT WITHOUT INJURY AND KEEPING THE AIRCRAFT DAMAGE TO A MINIMUM.

KEEPING SAFETY FIRST,

## The NTSB's investigation of this event (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB GAA16CA487](https://openairdocs.org/ntsb/GAA16CA487), Sep 1, 2016: Cessna 172 (N52950), Anchorage, AK, substantial damage. Probable cause: The airplane’s encounter with a developing sink hole during taxi on the ramp area.

## Other reports on N52950 (3)

Matched to the same aircraft by N-number and date.

- [Incident 20220506006459I](https://openairdocs.org/incident/20220506006459I), May 6, 2022: Cessna 172P (N52950), Palmer, AK, Minor damage. [privacy data omitted] Flying a Cessna 172P (N52950) on 06 may 2022 at approx... 10:15L/18:15Z. With the intent of landing on an off airport gravel surface…
- [Incident 20090225025079I](https://openairdocs.org/incident/20090225025079I), Feb 25, 2009: Cessna 172P (N52950), Anchorage, AK, No damage. The pilot was doing a touch and go and, while the pilot was resetting the flaps, the plane veered to the left when it encountered ice. It clipped a runway…
- [Incident 19851115065479I](https://openairdocs.org/incident/19851115065479I), Nov 15, 1985: Cessna 172P (N52950), Crooked Creek, AK, Minor damage. Landed on river ice after sudden loss of power and vibration. Number 2 cylinder pushrod assemblies bent, broken.

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

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