# NTSB DEN86LA168: Cessna 172K, N79221, Bosler, WY, June 21, 1986

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: June 21, 1986, 08:00 local (14:00 UTC)
- Place: Bosler, WY
- Coordinates: 41.579795, -105.6893 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.5798&lon=-105.6893&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 2 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16986
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN86LA168
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16986/pdf
- Page: https://openairdocs.org/ntsb/DEN86LA168

## Sequence of events

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

- In flight encounter with weather, takeoff - initial climb
  - weather condition - gusts (contributing factor)
  - preflight planning/preparation - poor, pilot in command (cause)
  - terrain condition - ditch (contributing factor)
  - weather condition - high density altitude (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled
  - ground loop/swerve - inadvertent, pilot in command

## Analysis

ACCORDING TO THE PLT, THE ACFT HAD JUST BECOME AIRBORNE WHEN IT ENCOUNTERED A GUST OF WIND WHILE SIMULTANEOUSLY CROSSING A GULLY, LOST LIFT & DESCENDED UNTIL GROUND CONTACT. THE PLT ALSO INDICATED THERE WAS A 'DENSITY ALTITUDE PROBLEM.' THE DENSITY ALTITUDE WAS CALCULATED TO BE ABOUT 9,100 FT.

## Aircraft

- Registration: [N79221](https://openairdocs.org/deregistered/N79221-2013-08-28), registration cancelled 2013-08-28, S/N 17257973, built 1969 (OpenAirDocs)
- Reported make and model: CESSNA 172K
- Registry model: [Cessna 172K](https://openairdocs.org/model/cessna-172k) (registry code 2072430) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 17257973
- Airframe hours: 3400
- Engines: LYCOMING O-360-A4A 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Norman R. Tilford
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, June 17, 1986, 16 hours before
- Destination: BO;, BILLINGS, MT

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 51; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 794 total, 794 in this make and model, 790 as pilot in command, 63 in the last 90 days, 8 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 250° at 5 knots, gusting 10
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 63 °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 19860621027059A](https://openairdocs.org/incident/19860621027059A), Jun 21, 1986: Cessna 172K, Bosler, WY, Substantial damage. Could not climb out of ground effect after high density altitude takeoff. Lost lift over a gully,struck the ground.

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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