# NTSB SEA84FA015: Cessna 150K, N5631G, Near Challis, ID, October 31, 1983

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: October 31, 1983, 09:57 local (16:57 UTC)
- Place: Near Challis, ID
- Coordinates: 44.649448, -114.150321 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=44.6494&lon=-114.1503&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 2 fatal
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 39781
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA84FA015
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/39781/pdf
- Page: https://openairdocs.org/ntsb/SEA84FA015

## Sequence of events

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

- Loss of control - in flight, maneuvering - turn to reverse direction
  - in-flight planning/decision - improper, pilot in command (cause)
  - terrain condition - high terrain (contributing factor)
  - terrain condition - mountainous/hilly (contributing factor)
  - terrain condition - rising (contributing factor)
  - weather condition - high density altitude (contributing factor)
  - weather condition - fog (contributing factor)
  - maneuver - initiated, pilot in command (contributing factor)
  - airspeed - inadequate, pilot in command (cause)
  - stall - inadvertent, pilot in command
- In flight collision with terrain/water, maneuvering - turn to reverse direction

## Analysis

A WITNESS AT THE CHALLIS ARPT OBSERVED THE ACFT TAKEOFF, THEN TURN & DEPART TOWARD THE WEST. IT WAS FOUND THE NEXT DAY NEAR CHALLIS CREEK ABOUT 16 MI WEST OF CHALLIS. IMPACT OCCURRED IN A RELATIVELY FLAT AREA IN A NARROW WOODED VALLEY, AT AN ELEVATION OF ABOUT 7,400 FT. THERE WAS EVIDENCE THAT THE ACFT HAD TURNED & WAS HEADED TOWARD THE CREEK WHEN IT CRASHED. FOREST SERVICE PERSONNEL REPORTED THAT THE HIGHER ELEVATIONS & VALLEY IN THAT AREA WERE COVERED WITH FOG.

## Aircraft

- Registration: N5631G (not matched to a registry record)
- Reported make and model: CESSNA 150K
- Category: Airplane
- Serial number: 150-71131
- Engines: CONTINENTAL O-200-A 100 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Personal, Part 91
- Registered owner: Sherman J. Hansen
- Airworthiness certificate: Standard, Normal
- Departed: U15, CHALLIS, ID
- Destination: BOI, BOISE, ID

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 36; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; toxicology performed; flight hours: 82 total, 82 in this make and model, 40 as pilot in command

## Weather

- Conditions: Visual (VMC), Day
- Temperature: 32 °F, dew point 34 °F
- Observed at: U15, 12 nm away

## 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 19831031056159A](https://openairdocs.org/incident/19831031056159A), Oct 31, 1983: Cessna 150K, Challis, ID, Destroyed, 1 fatal. May have been following a creek and struck trees that were obscured by valley fog that was forecast for the area.

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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