# NTSB ANC90LA055: Piper PA-11, N4904M, Knik Clacier, AK, April 13, 1990

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: April 12, 1990, 20:15 local (Apr 13, 1990, 04:15 UTC)
- Place: Knik Clacier, AK
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report March 5, 1993
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5351
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC90LA055
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5351/pdf
- Page: https://openairdocs.org/ntsb/ANC90LA055

## Probable cause

A FOREIGN OBJECT (TOOL) HAD JAMMED THE AILERON CONTROLS TO THE RIGHT AS THE PILOT WAS MANEUVERING THE AIRCRAFT FOR A LOW APPROACH TO A STRIP.

## Sequence of events

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

- Loss of control - in flight, maneuvering
  - flt control syst,aileron control - foreign object (cause)
  - flt control syst,aileron control - jammed (cause)
- In flight collision with terrain/water, maneuvering

## Analysis

THE PILOT ELECTED TO MAKE A LOW APPROACH OVER A GRAVEL BAR BEFORE LANDING. HE STATED THAT WHILE ROLLING OUT OF A TURN, THE ELEVATOR CONTROL JAMMED TO THE RIGHT. SUBSEQUENTLY, THE AIRPLANE SPIRALED TO THE TERRAIN, THEN CRASHED. AN EXAMINATION REVEALED THAT A SET OF CHANNEL LOCKS HAD SLIPPED UNDER THE FLOOR BOARD AND INTO THE FLIGHT CONTROLS.

## Aircraft

- Registration: [N4904M](https://openairdocs.org/deregistered/N4904M-2013-07-02), registration cancelled 2013-07-02, S/N 11-426, built 1947 (OpenAirDocs)
- Reported make and model: PIPER PA-11
- Registry model: [Piper PA-11](https://openairdocs.org/model/piper-pa-11) (registry code 7101102) (OpenAirDocs)
- Registry engine: [Continental A&C65 series](https://openairdocs.org/engine/continental-a-c65-series) (registry code 17003, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 11426
- Engines: LYCOMING O-290-D 125 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Stanley Wick
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, October 21, 1989, 18 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 33; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 482 total, 322 in this make and model, 482 as pilot in command, 9 in the last 90 days, 9 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 270° at 5 knots
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 50 °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 19900412009129A](https://openairdocs.org/incident/19900412009129A), Apr 12, 1990: Piper PA11, Knik Glacier, AK, Substantial damage. Control stick jammed in right turn at low altitude. Struck ground. Found channel lock pliers jammed rear stick.

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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