# NTSB ANC92LA172: Piper PA-12-150, N2577M, Upper Yantarni, AK, September 14, 1992

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: September 13, 1992, 20:00 local (Sep 14, 1992, 04:00 UTC)
- Place: Upper Yantarni, AK
- Coordinates: 56.960975, -158.579101 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=56.9610&lon=-158.5791&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 2 minor
- Status: Completed, report May 26, 1993
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5811
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC92LA172
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5811/pdf
- Page: https://openairdocs.org/ntsb/ANC92LA172

## Probable cause

PILOT IN COMMAND INADVERTANT ENCOUNTER WITH AERODYNAMIC STALL DURING LOW LEVEL APPROACH TURN.  FACTOR AFFECTING THE ACCIDENT WAS: THE PILOT'S APPROACH PROCEDURE/TECHNIQUE TO FLY VFR APPROACH PATTERN AT 50 FEET AGL.

## Sequence of events

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

- In flight collision with terrain/water, approach - vfr pattern - base leg/base to final
  - stall/mush - inadvertent, pilot in command (cause)
  - procedure inadequate, pilot in command (contributing factor)

## Analysis

THE PILOT OF A WHEEL EQUIPPED PA12 ENCOUNTERED AN APPROACH TURN STALL WHILE MANEUVERING FOR LANDING FROM A 50 FOOT PATTERN ALTITUDE AT REMOTE GRAVEL BAR LOCATION ON ALASKA PENINUSLA. THE PILOT AND PAX RECVD MINOR INJURIES AND ACFT WAS SUBSTANTIALLY DAMAGED.

## Aircraft

- Registration: [N2577M](https://openairdocs.org/aircraft/N2577M), registered now, S/N 12-1051, built 1946 (OpenAirDocs)
- Reported make and model: PIPER PA-12-150
- Registry model: [Piper PA-12](https://openairdocs.org/model/piper-pa-12) (registry code 7101202) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 12-1051
- Airframe hours: 5642
- Engines: LYCOMING O-320-A2B 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Floyd M. Krupinski
- Registered owner: Floyd M. Krupinski
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, September 2, 1992, 32 hours before
- Departed: NAKALILOK, AK
- Destination: YANTARNI CREEK, AK

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 47; commercial; airplane ratings: single-engine land, multi-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 6,680 total, 350 in this make and model, 4,100 as pilot in command, 40 in the last 90 days, 32 in the last 30 days, 5 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 10° at 5 knots
- Visibility: 30 statute miles
- Temperature: 50 °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 19920913036649A](https://openairdocs.org/incident/19920913036649A), Sep 13, 1992: Piper PA12, Upper Yantarni, AK, Substantial damage. Stalled while maneuvering for landing on a gravel bar. Blamed windshear.

## Other investigations on N2577M (2)

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 DEN84LA132](https://openairdocs.org/ntsb/DEN84LA132), Apr 20, 1984: Piper PA-12 (N2577M), Jackson, WY, substantial damage
- [NTSB SEA68D0243](https://openairdocs.org/ntsb/SEA68D0243), Feb 6, 1968: Piper PA-12 (N2577M), Mccall, ID, 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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