# NTSB DEN86FA149: American AA-1 Yankee, N5935L, Cheyenne, WY, June 4, 1986

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Field investigation · Final report
- Date: June 4, 1986, 07:51 local (13:51 UTC)
- Place: Cheyenne, WY
- Coordinates: 41.37062, -104.849601 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.3706&lon=-104.8496&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious, 1 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16826
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN86FA149
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16826/pdf
- Page: https://openairdocs.org/ntsb/DEN86FA149

## Sequence of events

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

- In flight collision with terrain/water, takeoff - initial climb
  - mixture - improper, pilot in command (cause)
  - lack of familiarity with aircraft, pilot in command (contributing factor)
  - aircraft weight and balance - exceeded, pilot in command (cause)
  - lack of familiarity with geographic area, pilot in command (contributing factor)

## Analysis

DURING TAKEOFF ON A 4,997 FOOT LONG RWY, THE ACFT BECAME AIRBORNE, SETTLED BACK ONTO THE RWY AND LIFTED OFF AGAIN JUST PRIOR TO REACHING THE END OF THE RWY. AFTER TAKEOFF THE PLT WAS NOT ABLE TO MAINTAIN FLT. THE ACFT IMPACTED ON A STREET, TRAVELED 30 FEET, STRUCK A WOODEN FENCE AND CAME TO REST AGAINST A TREE ON THE FRONT LAWN OF A PRIVATE RESIDENCE. MOST OF THE PLT'S FLT EXPERIENCE WAS IN AREAS WITH ELEVATIONS NEAR SEA LEVEL. HE STATED HE WAS NOT AWARE THE MIXTURE SHOULD BE LEANED DURING TAKEOFF FROM HIGH ALT ARPTS AS THE ACFT OWNER MANUAL SUGGESTS. CHEYENNE ARPT ELEVATION IS 6,150 FT MSL. THE ACFT WAS ALSO DETERMINED TO HAVE BEEN 35 LBS OVER MAX GROSS WEIGHT AT TAKEOFF.

## Aircraft

- Registration: [N5935L](https://openairdocs.org/deregistered/N5935L-2015-05-13), registration cancelled 2015-05-13, S/N AA1-0235, built 1969 (OpenAirDocs)
- Reported make and model: AMERICAN AA-1 YANKEE (AA-1 YANKE)
- Registry model: [American AA-1](https://openairdocs.org/model/american-aa-1) (registry code 0630610) (OpenAirDocs)
- Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs)
- Category: Airplane
- Serial number: AA1-0235
- Airframe hours: 2179
- Engines: LYCOMING O-235-C2C 108 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Robert G. Hostetler
- Airworthiness certificate: Standard, Utility; Standard, Normal
- Last inspection: Annual, May 19, 1986, 12 hours before
- Departed: CYS, CHEYENNE, WY
- Destination: 3V3, FLAGLER, CO
- Airport: CYS, Cheyenne, runway 34, 4,997 × 150 ft, concrete

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 55; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 123 total, 12 in this make and model, 91 as pilot in command, 13 in the last 90 days, 11 in the last 30 days, 6 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 350° at 10 knots
- Visibility: 20 statute miles
- Lowest ceiling: 1,400 ft overcast
- Temperature: 57 °F, dew point 54 °F
- Altimeter: 30.00 inHg
- Observed at: CYS, 1 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 19860604021409A](https://openairdocs.org/incident/19860604021409A), Jun 4, 1986: Gulstm AA1, Cheyenne, WY, Substantial damage. Aircraft failed to climb after takeoff and hit fence. Pilot failed to lean mixture at high density altitude field.

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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