# NTSB ANC91LA129: Cessna 172, N7966B, Montague Island, AK, August 19, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: August 19, 1991, 09:00 local (17:00 UTC)
- Place: Montague Island, AK
- Coordinates: 60.050102, -149.329193 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=60.0501&lon=-149.3292&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report March 24, 1993
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5605
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC91LA129
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5605/pdf
- Page: https://openairdocs.org/ntsb/ANC91LA129

## Probable cause

THE PILOT'S FAILURE TO MAINTAIN CONTROL OF THE AIRPLANE DURING THE LANDING ROLL. A FACTOR WAS THE UNSUITABLE TERRAIN SELECTED FOR LANDING BY THE PILOT, WHICH WAS LOOSE GRAVEL, ROUGH AND UNEVEN.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of control - on ground/water, landing - roll
  - terrain condition - loose gravel/sandy (contributing factor)
  - directional control - not maintained, pilot in command (cause)
  - terrain condition - rough/uneven (contributing factor)
  - unsuitable terrain or takeoff/landing/taxi area - not identified, pilot in command (contributing factor)
- Nose over, landing - roll

## Analysis

FOLLOWING THE BEACH LANDING AND DURING THE LANDING ROLL, THE PILOT LOST DIRECTIONAL CONTROL OF THE AIRPLANE.  THE AIRPLANE THEN NOSED OVER ON ITS BACK.

## Aircraft

- Registration: [N7966B](https://openairdocs.org/aircraft/N7966B), registered now, S/N 29766 (OpenAirDocs)
- Reported make and model: CESSNA 172
- Registry model: [Cessna 172](https://openairdocs.org/model/cessna-172) (registry code 2072402) (OpenAirDocs)
- Registry engine: [Continental 0-300 series](https://openairdocs.org/engine/continental-0-300-series) (registry code 17022, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 26766
- Airframe hours: 5050
- Engines: LYCOMING O-360-A1A 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Ervin Dedeker
- Registered owner: Ervin Dedeker
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, June 13, 1991, 40 hours before
- Departed: MRI, ANCHORAGE, AK
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 64; private; airplane ratings: single-engine land, single-engine sea; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 1,600 total, 1,400 in this make and model, 1,600 as pilot in command, 60 in the last 90 days, 15 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 140° at 6 knots
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 55 °F, dew point 41 °F
- Altimeter: 30.00 inHg

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19910819034809A](https://openairdocs.org/incident/19910819034809A), Aug 19, 1991: Cessna 172, Montague Island, AK, Substantial damage. Lost control landing on a beach. Nosed over in soft sand. Blamed brakes. No defects found.

## Other investigations on N7966B (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 ANC98LA131](https://openairdocs.org/ntsb/ANC98LA131), Aug 15, 1998: Cessna 172 (N7966B), Palmer, AK, substantial damage. Probable cause: Fatigue of the forward end of the engine crankshaft resulting in separation of the propeller assembly, and the operator's failure to comply with a required maintenance procedure. A factor was uneven…

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.

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