# NTSB ANC90LA074: Cessna 150, N66425, Palmer, AK, May 23, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: May 23, 1990, 10:00 local (18:00 UTC)
- Place: Palmer, AK
- Coordinates: 61.619167, -148.979721 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=61.6192&lon=-148.9797&mi=10
- Phase of flight: [Other](https://openairdocs.org/ntsb-phases/800) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report August 28, 1992
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5369
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC90LA074
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5369/pdf
- Page: https://openairdocs.org/ntsb/ANC90LA074

## Probable cause

THE FLIGHT INSTRUCTOR'S FAILURE TO USE CARBURETOR HEAT DURING A SIMULATED ENGINE FAILURE. THE ROUGH TERRAIN AND WEATHER CONDITIONS CONDUCIVE TO CARBURETOR ICING WERE CONTRIBUTING FACTORS.

## Sequence of events

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

- Loss of engine power(partial) - nonmechanical, other
  - weather condition - carburetor icing conditions (contributing factor)
  - carburetor heat - not used, pilot in command(cfi) (cause)
- Forced landing, landing - flare/touchdown
- Nose over, landing - flare/touchdown
  - terrain condition - rough/uneven (contributing factor)

## Analysis

POWER WAS REDUCED AT 1,000-1,200 FT AGL FOR A SIMULATED ENGINE FAILURE. POWER WAS THEN ADDED FOR RECOVERY AT 150 FT AGL BUT THE ENGINE DID NOT RESPOND. THE AIRPLANE NOSED OVER IN A FRESHLY PLOWED FIELD. THE TEMP/DEW POINT WAS 45/32. THE CFI STATED THAT HE THOUGHT THE OUTSIDE AIR TEMP AT THE TIME WAS 55-60 DEG AND THAT THE USE OF CARB HEAT WAS NOT WARRANTED FOR THE MANEUVER.

## Aircraft

- Registration: [N66425](https://openairdocs.org/aircraft/N66425), registered now, S/N 15076039, built 1974 (OpenAirDocs)
- Reported make and model: CESSNA 150
- Registry model: [Cessna 150M](https://openairdocs.org/model/cessna-150m) (registry code 2071830) (OpenAirDocs)
- Registry engine: [Continental 0-200 series](https://openairdocs.org/engine/continental-0-200-series) (registry code 17020, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 15076039
- Airframe hours: 3351
- Engines: CONTINENTAL O-200-A 100 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Nugget Aviation
- Registered owner: Thomas A Bishop
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, May 19, 1990, 5 hours before
- Departed: PAQ, PALMER, AK

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 22; commercial, flight instructor; airplane ratings: single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: right; flight hours: 348 total, 33 in this make and model, 283 as pilot in command, 26 in the last 90 days, 14 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 10° at 6 knots
- Visibility: 40 statute miles
- Lowest ceiling: 12,000 ft broken
- Temperature: 45 °F, dew point 30 °F
- Altimeter: 29.00 inHg
- Observed at: PAQ, 4 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 19900523017149A](https://openairdocs.org/incident/19900523017149A), May 23, 1990: Cessna 150M, Palmer, AK, Substantial damage. Engine failed to respond after practice forced landing approach . CFI unaware of carb icing conditions.

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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