# NTSB ANC90LA093: Piper PA-18-160, N4431Z, Big Lake, AK, June 22, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: June 21, 1990, 19:00 local (Jun 22, 1990, 03:00 UTC)
- Place: Big Lake, AK
- Location: 61.5450° N, 149.8180° W: Placed by OpenAirDocs: center of Big Lake, AK, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=61.5450&lon=-149.8180&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 October 2, 1992
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5385
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC90LA093
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5385/pdf
- Page: https://openairdocs.org/ntsb/ANC90LA093

## Probable cause

LOSS OF ENGINE POWER FOR UNDETERMINED REASONS RESULTING IN AN OFF AIRPORT LANDING IN A DITCH.

## Sequence of events

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

- Loss of engine power, takeoff - initial climb
  - reason for occurrence undetermined (cause)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - ditch

## Analysis

THE AIRPLANE HAD SPENT THREE YEARS IN THE SHOP BEING REBUILT AND THIS WAS ITS FIRST FLIGHT. THE PILOT-IN-COMMAND TOPPED OFF THE FUEL TANKS, PERFORMED A RUNUP AND THEN SAT ON THE END OF THE RUNWAY WHILE HE ATTEMPTED TO FIX THE COMMUNICATION RADIO. HE THEN TAXIED ONTO THE RUNWAY AND STARTED THE TAKEOFF. UPON REACHING 150 FEET ABOVE THE GROUND HE REDUCED THE POWER BY 200 RPM AND THE ENGINE DIED SUDDENLY. HE ATTEMPTED TO LAND ON A ROAD STRAIGHT AHEAD. THE AIRPLANE LANDED SHORT IN THE DITCH. SUBSEQUENT EXAMINATION AND ENGINE RUN SHOWED NO MECHANICAL IRREGULARITIES WITH THE ENGINE OR AIRPLANE FUEL SYSTEM.

## Aircraft

- Registration: [N4431Z](https://openairdocs.org/aircraft/N4431Z), registered now, S/N 188769 (OpenAirDocs)
- Reported make and model: PIPER PA-18-160
- Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs)
- Category: Airplane
- Serial number: 18-8769
- Engines: LYCOMING O-320-B2B 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Kim Irwin
- Registered owner: Kimmeth J. Irwin
- Airworthiness certificate: Standard, Normal
- Airport: BGQ, Big Lake, runway 24, 2,400 × 75 ft, gravel

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 46; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: front; flight hours: 415 total, 340 in this make and model, 415 as pilot in command

## Weather

- Conditions: Visual (VMC), Day
- Wind: 330° at 16 knots
- Visibility: 60 statute miles
- Lowest ceiling: none
- Temperature: 64 °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 19900621021529A](https://openairdocs.org/incident/19900621021529A), Jun 21, 1990: Piper STCPA18, Big Lake, AK, Substantial damage. On test flight after 3 year rebuild engine quit. Struck ditch. Had run engine lengthy on ground without carb heat.

## Other investigations on N4431Z (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 ANC86LA024](https://openairdocs.org/ntsb/ANC86LA024), Feb 7, 1986: Piper PA-18 (N4431Z), Wasilla, 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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