# NTSB DEN84LA083: Maule M-4S, N9832M, Three Forks, MT, February 5, 1984

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: February 5, 1984, 11:20 local (18:20 UTC)
- Place: Three Forks, MT
- Coordinates: 45.909244, -111.429512 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.9092&lon=-111.4295&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 2 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16331
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN84LA083
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16331/pdf
- Page: https://openairdocs.org/ntsb/DEN84LA083

## Sequence of events

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

- In flight collision with terrain/water, maneuvering
  - ice/frost removal from aircraft - inadequate, pilot in command (contributing factor)
  - airspeed(vs) - reduced (contributing factor)
  - in-flight planning/decision - improper, pilot in command (cause)
  - proper altitude - not maintained, pilot in command (cause)
  - pull-up - attempted, pilot in command
  - stall/mush - inadequate, pilot in command (cause)

## Analysis

THE PLT WAS FLYING LOW TOWARD RISING TERRAIN. THE AIRSPEED SLOWED TO THE POINT THAT THE POINT THAT THE ACFT MUSHED INTO THE GROUND AND CARTWHEELED. THE PLT SAID HE HAD NOT REMOVED ALL THE FROST ON THE WINGS PRIOR TO FLT AND HE THOUGHT THE STALL SPEED WAS RAISED BY THE FROST.

## Aircraft

- Registration: [N9832M](https://openairdocs.org/deregistered/N9832M-2013-05-30), registration cancelled 2013-05-30, S/N 2-S, built 1966 (OpenAirDocs)
- Reported make and model: MAULE M-4S
- Registry model: [Maule M-4S](https://openairdocs.org/model/maule-m-4s) (registry code 5460128) (OpenAirDocs)
- Registry engine: [Continental 0-300 series](https://openairdocs.org/engine/continental-0-300-series) (registry code 17022, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 2-S
- Airframe hours: 1211
- Engines: CONTINENTAL O-300-A 145 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Alton G. Gaskill
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, April 15, 1983
- Destination: 5U3, ENNIS, MT

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 53; private; airplane ratings: single-engine sea, single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 715 total, 715 in this make and model, 3 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 60 statute miles
- Lowest ceiling: none
- Temperature: 19 °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 19840205002149A](https://openairdocs.org/incident/19840205002149A), Feb 5, 1984: Maule M4S, Three Forks, MT, Substantial damage. Aircraft crashed during low flight operation when pilot stalled airplane. Pilot said there was frost on wings.

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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