# NTSB DEN86FA223: Cessna 172, N4016F, Ten Sleep, WY, August 9, 1986

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: August 9, 1986, 13:30 local (19:30 UTC)
- Place: Ten Sleep, WY
- Coordinates: 44.029052, -107.439056 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=44.0291&lon=-107.4391&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal, 1 serious
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16842
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN86FA223
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16842/pdf
- Page: https://openairdocs.org/ntsb/DEN86FA223

## Sequence of events

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

- In flight collision with terrain/water, landing - roll
  - in-flight planning/decision - improper, pilot in command (cause)
  - became lost/disoriented - inadvertent, pilot in command (cause)
  - terrain condition - mountainous/hilly (contributing factor)
  - terrain condition - rising (contributing factor)
  - precautionary landing - attempted, pilot in command
  - aircraft performance,climb capability - exceeded
  - proper climb rate - not possible, pilot in command (contributing factor)

## Analysis

THE PLT BECAME LOST/DISORIENTED AND INADVERTENTLY ENTERED THE NARROW CANYON IN A MOUNTAIN PASS. HE ATTEMPTED TO LAND ON A PUBLIC HIGHWAY AT 7,500 FEET MSL WHEN IT BECAME APPARENT THE ACFT WOULD NOT CLIMB FAST ENOUGH TO CLEAR RAPIDLY RISING TERRAIN AND THAT IT WAS NOT POSSIBLE TO REVERSE COURSE IN THE NARROW PASS. ON SHORT FINAL THE PLT OBSERVED VEHICULAR TRAFFIC APPROACH FROM AROUND A SWITCHBACK CURVE AND VEERED OFF THE HIGHWAY WHERE THE ACFT IMPACTED STEEP, ROCKY TERRAIN.

## Aircraft

- Registration: [N4016F](https://openairdocs.org/deregistered/N4016F-1992-12-01), registration cancelled 1992-12-01, S/N 36916 (OpenAirDocs)
- Reported make and model: CESSNA 172
- Registry model: [Cessna 172](https://openairdocs.org/model/cessna-172) (registry code 2072402) (OpenAirDocs)
- Category: Airplane
- Serial number: 36916
- Airframe hours: 4044
- Engines: CONTINENTAL O-300-D 145 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: John W. Dunn
- Registered owner: Raymond Negaard
- Airworthiness certificate: Standard, Normal; Standard, Utility
- Last inspection: Annual, July 7, 1986, 94 hours before
- Departed: CDR, CHADRON, NE
- Destination: THP, THERMOPOLIS, WY

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 50; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 257 total, 257 in this make and model, 191 as pilot in command, 16 in the last 90 days, 5 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 280° at 6 knots
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 73 °F, dew point 48 °F
- Altimeter: 30.00 inHg
- Observed at: WRL, 31 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 19860809075549A](https://openairdocs.org/incident/19860809075549A), Aug 9, 1986: Cessna 172, Ten Sleep, WY, Destroyed, 1 fatal. The aircraft was unable to climb above rising terrain. The pilot was disoriented and unable to use available aids.

## Other investigations on N4016F (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 MKC86LA003](https://openairdocs.org/ntsb/MKC86LA003), Oct 5, 1985: Cessna 172 (N4016F), Guilford, MO, 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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