# NTSB SEA92LA131: Stinson 108-3, N6470M, Corbett, OR, June 23, 1992

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: June 22, 1992, 18:20 local (Jun 23, 1992, 01:20 UTC)
- Place: Corbett, OR
- Coordinates: 45.51054, -122.209457 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.5105&lon=-122.2095&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report September 14, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 42837
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA92LA131
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42837/pdf
- Page: https://openairdocs.org/ntsb/SEA92LA131

## Probable cause

THE FAILURE OF THE FLOAT ATTACH FITTING, AND THE SEPARATION OF THE FLOATS FROM THE AIRCRAFT.

## Sequence of events

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

- Airframe/component/system failure/malfunction, takeoff - initial climb
  - landing gear,float assembly - failure,total (cause)
  - landing gear,float assembly - separation (cause)
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - water (contributing factor)

## Analysis

AFTER TAKING OFF FROM ROUGH WATER, AND CLIMBING TO ABOUT 200 FEET ABOVE THE RIVER, THE PILOT OF THE STINSON FLOATPLANE HEARD A LOUD POP IN THE RIGHT FRONT AREA OF THE AIRCRAFT. THIS WAS FOLLOWED BY A SEVERE VIBRATION, AND BY THE PILOT'S DECISION TO MAKE A PRECAUTIONARY LANDING. THE PILOT, WHO DID NOT REALIZE THAT THE FLOATS HAD SEPARATED FROM THE AIRPLANE, ATTEMPTED A NORMAL WATER LANDING, WHEREUPON THE AIRCRAFT FUSELAGE IMPACTED THE WATER AND ULTIMATELY SANK.

## Aircraft

- Registration: [N6470M](https://openairdocs.org/aircraft/N6470M), registered now, S/N 108-4470, built 1947 (OpenAirDocs)
- Reported make and model: STINSON 108-3
- Registry model: [Stinson 108-3](https://openairdocs.org/model/stinson-108-3) (registry code 9230408) (OpenAirDocs)
- Registry engine: [Continental O-470 series](https://openairdocs.org/engine/continental-o-470-series) (registry code 17026, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 108-4470
- Airframe hours: 2000
- Engines: CONTINENTAL O-470-J 230 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Anderson, Allan L.
- Registered owner: Anderson, Allan L.
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, March 24, 1991, 80 hours before
- Destination: 3S1, LAKE OSWEGO, OR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 61; private; airplane ratings: single-engine land, single-engine sea; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 550 total, 70 in this make and model, 520 as pilot in command, 20 in the last 90 days, 5 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 270° at 35 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 100 °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 19920622021439A](https://openairdocs.org/incident/19920622021439A), Jun 22, 1992: Univar 1083, Corbett, OR, Substantial damage. After rough water takeoff. Loud pop and floats fell off. Unaware pilot aborted takeoff. Impacted water and sank.

## Other investigations on N6470M (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 SEA79DYM10](https://openairdocs.org/ntsb/SEA79DYM10), Jan 14, 1979: Stinson 108-3 (N6470M), Dallesport, WA, 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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