# NTSB ANC91LA034: Cessna 120, N77316, Atigan Pass, AK, March 11, 1991

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: March 11, 1991, 13:15 local (17:15 UTC)
- Place: Atigan Pass, AK
- Coordinates: 70.429801, -149.289566 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=70.4298&lon=-149.2896&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 2 minor
- Status: Completed, report May 5, 1993
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5525
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC91LA034
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5525/pdf
- Page: https://openairdocs.org/ntsb/ANC91LA034

## Probable cause

THE PILOT CONTINUED TO FLY VFR INTO IFR CONDITIONS. RELATED TO THE ACCIDENT WERE: LOW CEILINGS, WHITEOUT CONDITIONS, AND THE MOUNTAINOUS TERRAIN.

## Analysis

THE PILOT STATED THAT JUST BEFORE REACHING A 4,700 FOOT MOUNTAIN PASS, HE ENCOUNTERED RAPIDLY DETERIORATING FLIGHT VISIBILITY AND WHITEOUT CONDITIONS DUE TO SNOW-COVERED TERRAIN AND FALLING SNOW.  HE LOST SIGHT OF THE GROUND AND WAS UNABLE TO TURN THE AIRPLANE AROUND.  HE BEGAN A SLOW DESCENT AND CRASH LANDED ON THE SNOW-COVERED MOUNTAINSIDE.

## Sequence of events

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

- In flight encounter with weather, climb
  - weather condition - low ceiling (contributing factor)
  - vfr flight into imc - continued, pilot in command (cause)
  - weather condition - whiteout (contributing factor)
- In flight collision with terrain/water, descent
  - terrain condition - mountainous/hilly (contributing factor)

## Aircraft

- Registration: [N77316](https://openairdocs.org/deregistered/N77316-2012-10-22), registration cancelled 2012-10-22, S/N 11758, built 1946 (OpenAirDocs)
- Reported make and model: CESSNA 120
- Registry model: [Cessna 120](https://openairdocs.org/model/cessna-120) (registry code 2071402) (OpenAirDocs)
- Registry engine: [Continental C85 series](https://openairdocs.org/engine/continental-c85-series) (registry code 17008, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 11758
- Airframe hours: 2742
- Engines: CONTINENTAL C-85-12 85 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: John R. Deruyter
- Registered owner: Ross W. Miller
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, July 7, 1990, 40 hours before
- Departed: NONE, TULIK, AK
- Destination: NONE, NORTH POLE, AK

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 39; commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; flight hours: 2,080 total, 70 in this make and model, 1,900 as pilot in command, 69 in the last 90 days, 47 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 4 statute miles
- Lowest ceiling: 6,000 ft overcast
- Temperature: -26 °F, dew point -0 °F

## 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 19910311043779A](https://openairdocs.org/incident/19910311043779A), Mar 11, 1991: Cessna 120, Atigan Pass, AK, Substantial damage. Flew into heavy snow shower in a Pass. Unable to climb out of Pass. Crash landed on snow covered mountainside.

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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