# NTSB ANC91LA031: Champion 7GCBC, N7578F, Flat Top Mtn., AK, February 27, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: February 27, 1991, 13:00 local (17:00 UTC)
- Place: Flat Top Mtn., AK
- Coordinates: 61.409866, -149.170852 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=61.4099&lon=-149.1709&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report May 7, 1993
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5522
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC91LA031
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5522/pdf
- Page: https://openairdocs.org/ntsb/ANC91LA031

## Probable cause

THE PILOT'S FAILURE TO MAINTAIN DIRECTIONAL CONTROL OF THE AIRPLANE ON LANDING ROLL OUT IN UNSUITABLE TERRAIN. CONTRIBUTING TO THE ACCIDENT WAS THE ROUGH AND UNEVEN TERRAIN.

## 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 - rough/uneven (contributing factor)
  - directional control - not maintained, pilot in command (cause)
- Nose over, landing - roll

## Analysis

AFTER TOUCHDOWN ON A MOUNTAIN TOP, THE PILOT LOST DIRECTIONAL CONTROL OF THE AIRPLANE.  THE AIRPLANE THEN NOSED OVER ON ITS BACK.  THE LANDING AREA WAS ROUGH AND UNEVEN.

## Aircraft

- Registration: [N7578F](https://openairdocs.org/aircraft/N7578F), registered now, S/N 233-70 (OpenAirDocs)
- Reported make and model: CHAMPION 7GCBC
- Registry model: [Champion 7GCBC](https://openairdocs.org/model/champion-7gcbc) (registry code 21101PK) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 23370
- Airframe hours: 1750
- Engines: LYCOMING O-320 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: John Davis
- Registered owner: John Davis
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, March 3, 1990, 50 hours before
- Departed: ANC, ANCHORAGE, AK

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 32; private; airplane ratings: single-engine sea, multi-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 389 total, 365 in this make and model, 389 as pilot in command, 8 in the last 90 days, 3 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 97 statute miles
- Lowest ceiling: none
- Temperature: 39 °F, dew point 16 °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 19910227003609A](https://openairdocs.org/incident/19910227003609A), Feb 27, 1991: Bbavia 7GCBC, Flat Top Mounta, AK, Substantial damage. Landed on icy snow on mountain top. A ski twisted and dug in. Nosed over.

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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