# NTSB ANC87LA060: Piper PA-12, N92524, Yentna River, AK, April 18, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: April 18, 1987, 13:00 local (21:00 UTC)
- Place: Yentna River, AK
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report March 30, 1988
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 4841
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC87LA060
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/4841/pdf
- Page: https://openairdocs.org/ntsb/ANC87LA060

## Sequence of events

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

- On ground/water collision with object, takeoff - roll/run
  - terrain condition - high vegetation (contributing factor)
  - terrain condition - loose gravel/sandy (contributing factor)
  - ground loop/swerve - not corrected, pilot in command (cause)
  - directional control - not maintained, pilot in command (cause)
- Nose over, takeoff - roll/run

## Analysis

THE PILOT STATED THAT DURING THE TAKEOFF ROLL ON THE GRAVEL BAR HE LOST DIRECTIONAL CONTROL OF THE AIRCRAFT CAUSING THE AIRCRAFT TO NOSE OVER ON ITS BACK.

## Aircraft

- Registration: N92524 (not matched to a registry record)
- Reported make and model: PIPER PA-12
- Category: Airplane
- Serial number: 1247
- Airframe hours: 260
- Engines: LYCOMING O-320 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: William H. Tinney
- Registered owner: William E. Clay
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, May 27, 1986, 40 hours before
- Departed: Z41, ANCHORAGE, AK

## 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: 158 total, 158 in this make and model, 57 as pilot in command, 25 in the last 90 days, 15 in the last 30 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 320° at 5 knots
- Visibility: 90 statute miles
- Lowest ceiling: 10,000 ft broken
- Temperature: 39 °F, dew point 30 °F
- Altimeter: 29.00 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 19870418053449A](https://openairdocs.org/incident/19870418053449A), Apr 18, 1987: Piper STCPA12, Yentna River, AK, Substantial damage. The aircraft wing struck a tree during takeoff from a frozen swamp.

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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