Thorp T-18 accident near Kent, Washington, May 9, 2008
On May 9, 2008 at about 11:45 pm local time, a Thorp T-18, an amateur-built aircraft,, registered N8613A, was substantially damaged in an accident during initial climb near Kent, Washington (Crest Airpark airport). It was a personal flight under general aviation rules (Part 91). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The loss of engine power for undetermined reasons. Contributing to the accident were the lack of a suitable landing area and the pilot's failure to maintain an adequate airspeed while maneuvering in response to the loss of engine power.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 9, 2008 · about 11:45 pm local time
- Place
- Kent, Washington · Crest Airpark · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Thorp T-18, amateur-built · all T-18s on the register
- Registration
- N8613A · registry record · serial 48
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot had recently installed an overhauled carburetor and new air inlet on the airplane. Because the airplane had not been flown for about nine months, the pilot drained all of the old fuel out of the airplane and refueled it. Witnesses reported that the pilot performed an extensive engine run up that lasted 10 to 15 minutes, and with satisfactory results, the pilot decided to take the airplane around the airport traffic pattern. A witness based at the airport said that during the initial takeoff, the engine sound was smooth. As it continued, the witness heard the engine running rough. When the airplane flew past the witness about 300 feet above the runway, the witness saw two puffs of white smoke. The airplane appeared to have adequate airspeed and it was still climbing, although the engine was cutting out. The engine then cut out completely and the airplane continued straight ahead for about 1 second. The airplane entered a slow turn to the right, and when it had turned approximately 160 degrees, the right wing stalled and the airplane rolled into a spin. The airplane went out of view of the witness in a nose-down attitude of approximately 70 degrees. A friend of the pilot who was based at the airport said that when departing to the north as the pilot had done, there are limited options available for emergency landings. The fuel valve was found in the closed, or "off", position. Based on the length of the engine run up, the fuel selector was undoubtedly positioned correctly at takeoff and was most likely moved to the closed position by the pilot when he determined that a forced landing was inevitable. Post accident examination of the wreckage did not disclose any pre-impact mechanical anomalies. Due to damage sustained to the carburetor, no functional testing could be performed.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Loss of engine power (total) during initial climb defining event
- Aerodynamic stall/spin during emergency descent
- Collision with terrain or object (not controlled flight into terrain) during uncontrolled descent
The NTSB's findings
- cause Not determined › Not determined › (general) › (general) › Unknown/Not determined
- factor Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Airspeed › Not attained/maintained
- factor Environmental issues › Physical environment › Terrain › (general) › Contributed to outcome
Pilot
- Certificate: airline transport pilot, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 8,400 hours in all
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: fatal
The aircraft
- Airframe total time: 3,313.5 hours
- Last inspection: condition inspection, October 16, 2007; 0.5 hours since
- Maximum gross weight: 1,600 lb
- Seats: 2
- Landing gear: fixed
- Engine: Textron Lycoming O-320-E2D (piston); 0 hours total
- Fire on the ground
The flight
- Departed from: S36 Kent WA at 11:40 pm
- Flight plan: none
- Runway 33, 3,288 ft by 40 ft
Weather at the time
- Light: daylight
- Wind: from 250° at 4 knots
- Visibility: 10 statute miles
- Sky: overcast at 25,000 ft; a few clouds at 4,000 ft
- Temperature: 59°F (15°C), dew point 36°F (2°C)
- Altimeter: 30.07 inHg
- Observation at 11:53 pm from KSEA, 11 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.