# NTSB SEA89LA066: Thiessen RV-4, N504JT, Independence, OR, April 7, 1989

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: April 6, 1989, 19:15 local (Apr 7, 1989, 02:15 UTC)
- Place: Independence, OR
- Coordinates: 44.830211, -123.200805 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=44.8302&lon=-123.2008&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report January 22, 1991
- Report: Approved by Office Director
- NTSB case key (mKey): 40994
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA89LA066
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40994/pdf
- Page: https://openairdocs.org/ntsb/SEA89LA066

## Probable cause

FAILURE OF THE PROPELLER.  A RELATED FACTOR WAS THE OBSTRUCTION (TRANSMISSION LINE) IN THE EMERGENCY LANDING AREA.

## Sequence of events

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

- Airframe/component/system failure/malfunction, cruise
  - propeller system/accessories,blade - failure,total (cause)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing
  - object - wire,transmission (contributing factor)
  - maneuver - performed, pilot in command
  - stall/mush

## Analysis

THE PLT HAD INSTALLED A USED 'SCIMITAR' PROP WHILE WAITING FOR HIS TO BE REFINISHED. DURING A SPEED RUN AT 190 MPH, WITH ABOUT 2900 RPM, PART OF PROP SEPARATED. THE PLT SHUT DOWN THE ENG & INITIATED AN EMERGENCY LANDING. HOWEVER, WHILE MANEUVERING TO AVOID WIRES, AT ABOUT 25 TO 50 FT AGL, THE ACFT STALLED, THEN MUSHED INTO THE GROUND.

## Aircraft

- Registration: [N504JT](https://openairdocs.org/deregistered/N504JT-2010-03-15), registration cancelled 2010-03-15, S/N 799, built 1988 (OpenAirDocs)
- Reported make and model: THIESSEN RV-4
- Registry model: [Thiessen Jake VANS RV 4](https://openairdocs.org/model/thiessen-jake-vans-rv-4) (registry code 056089F) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: RV-4
- Airframe hours: 55
- Engines: LYCOMING O-320-E2D 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Part 91
- Operator: Jacob Thiessen
- Registered owner: Jacob Thiessen
- Last inspection: Unknown, April 5, 1989, 0 hours before
- Departed: 7S5

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 51; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: front; flight hours: 638 total, 55 in this make and model, 11 in the last 90 days, 4 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 360° at 5 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 61 °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 19890406006499A](https://openairdocs.org/incident/19890406006499A), Apr 6, 1989: Amtrvn VANSRV4, Independence, OR, Substantial damage. Special propeller blade broke off on test flight. Stalled maneuvering to avoid wires on forced landing.

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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