# NTSB ANC87LA161: Piper PA-18, N7051, Sparrevohn, AK, September 17, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 17, 1987, 15:00 local (23:00 UTC)
- Place: Sparrevohn, AK
- Location: 61.1031° N, 155.5775° W: Placed by OpenAirDocs: center of Sparrevohn Long Range Radar Site, AK, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=61.1031&lon=-155.5775&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 27, 1988
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 4923
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC87LA161
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/4923/pdf
- Page: https://openairdocs.org/ntsb/ANC87LA161

## Sequence of events

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

- In flight collision with object, takeoff - initial climb
  - object - tree(s) (contributing factor)
  - unsuitable terrain or takeoff/landing/taxi area - selected, pilot in command (cause)
  - aborted takeoff - not performed, pilot in command (cause)
  - terrain condition - rough/uneven (contributing factor)

## Analysis

THE PILOT OF THE AIRPLANE WAS AN ALASKA STATE TROOPER PERFORMING HIS OFFICIAL DUTIES AND WAS FLYING AN AIRPLANE OWNED AND OPERATED BY THE STATE OF ALASKA. HE HAD LANDED ON A REMOTE RIDGE TOP TO RECOVER ESSENTIAL ITEMS OF EVIDENCE FOR A PENDING CASE. UPON DEPARTURE FROM THE RIDGE, ROUGH TERRAIN PREMATURELY BOUNCED THE AIRPLANE INTO THE AIR AND THE PILOT WAS UNABLE TO GAIN SUFFICIENT AIRSPEED TO REMAIN AIRBORNE OR CLIMB. THE AIRPLANE STRUCK A SMALL TREE AND NOSED OVER.

## Aircraft

- Registration: [N7051](https://openairdocs.org/aircraft/N7051), registered now, S/N 18-2932, built 1953 (OpenAirDocs)
- Reported make and model: PIPER PA-18
- Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 18-2932
- Airframe hours: 8697
- Engines: LYCOMING O-320 SERIES 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Public aircraft, Part 91
- Operator: State Of Alaska
- Registered owner: State Of Alaska
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, July 31, 1987, 236 hours before
- Destination: MCG, MC GRATH, AK
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 40; commercial; airplane ratings: single-engine sea, single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: front; flight hours: 1,660 total, 936 in this make and model, 200 in the last 90 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 20° at 10 knots
- Visibility: 80 statute miles
- Lowest ceiling: none
- Temperature: 50 °F

## Other investigations on N7051 (4)

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 ANC07TA080](https://openairdocs.org/ntsb/ANC07TA080), Aug 11, 2007: Piper PA-18 (N7051), McGrath, AK, substantial damage. Probable cause: The pilot's failure to maintain control of the airplane during the landing roll. Contributing to the accident was rough and uneven terrain conditions.
- [NTSB ANC03TA072](https://openairdocs.org/ntsb/ANC03TA072), Jul 9, 2003: Piper PA-18-160 (N7051), Anchorage, AK, substantial damage. Probable cause: The pilot's selection of unsuitable terrain for landing, which resulted in an encounter with high brush.
- [NTSB ANC99TA061](https://openairdocs.org/ntsb/ANC99TA061), May 15, 1999: Piper PA-18 (N7051), Nome, AK, substantial damage. Probable cause: The pilot's failure to maintain directional control during landing. A factor in this accident was the crosswind.
- [NTSB ANC68F0100](https://openairdocs.org/ntsb/ANC68F0100), Feb 25, 1968: Piper PA-18 (N7051), King Salmon, AK, substantial damage

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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