# NTSB SEA84LA197: Aeronca 7AC, N83233, Prineville, OR, August 9, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: August 9, 1984, 10:00 local (17:00 UTC)
- Place: Prineville, OR
- Coordinates: 44.099124, -120.659439 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=44.0991&lon=-120.6594&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 39988
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA84LA197
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/39988/pdf
- Page: https://openairdocs.org/ntsb/SEA84LA197

## Sequence of events

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

- Loss of engine power(partial) - mech failure/malf, maneuvering
  - engine assembly,crankshaft - failure,total (cause)
  - remedial action - not possible, pilot in command
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing - flare/touchdown

## Analysis

WHILE MANEUVERING PLT HEARD A LOUD CHATTER COMING FROM THE ENGINE ACCOMPANIED BY A LOSS OF POWER. PLT REDUCED REMAINING POWER AND INITIATED A FORCED LANDING IN A ROUGH BARLEY FIELD. POST ACCIDENT INVESTIGATION REVEALED THE CRANKSHAFT BROKE NEAR THE NUMBER TWO CRANKTHROW. FURTHER INVESTIGATION REVEALED THE JOURNAL WAS IMPROPERLY GROUND.

## Aircraft

- Registration: [N83233](https://openairdocs.org/aircraft/N83233), registered now, S/N 7AC-1897, built 1946 (OpenAirDocs)
- Reported make and model: AERONCA 7AC
- Registry model: [Champion 7AC](https://openairdocs.org/model/champion-7ac) (registry code 21101MA) (OpenAirDocs)
- Registry engine: [Continental A&C65 series](https://openairdocs.org/engine/continental-a-c65-series) (registry code 17003, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 7AC-1897
- Engines: CONTINENTAL C-65-8 65 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: D. Twiss,L. Carter,R. Mcelroy
- Airworthiness certificate: Standard, Normal
- Departed: S39, PRINEVILLE, OR
- Airport: None

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; student; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 79 °F
- Altimeter: 30.00 inHg

## 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 19840809042079A](https://openairdocs.org/incident/19840809042079A), Aug 9, 1984: Bbavia 7AC, Prineville, OR, Substantial damage. Aircraft crashed during emergency landing after engine failure. Broken crankshaft caused engine failure.

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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