Flight Design GMBH CTSW accident near Haskell, Oklahoma, June 6, 2015
On June 6, 2015 at about 5:58 pm local time, a 2007 Flight Design GMBH CTSW, registered N535CT, was substantially damaged in an accident during initial climb near Haskell, Oklahoma (Haskell airport). It was a personal flight under general aviation rules (Part 91). 2 people had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The loss of engine power for reasons that could not be determined because a postaccident engine examination and test run did not reveal any evidence of preimpact malfunctions or failures that would have precluded normal operation.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 6, 2015 · about 5:58 pm local time
- Place
- Haskell, Oklahoma · Haskell · map
- Type
- Accident
- Injuries
- 2 people had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Flight Design GMBH CTSW, built 2007 · all CTSWs on the register
- Registration
- N535CT · no longer on the register · serial 07-05-01
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The sport pilot completed a preflight inspection of the airplane and noted that it had about 28 gallons of automotive fuel; he conducted a cross-country flight with no anomalies noted. After starting the engine before takeoff for the return flight, the pilot noticed that the engine gauges were normal but that the charging system had an inadequate output, so he shut down the engine. After consulting a mechanic, he restarted the engine and noted normal engine and charging indications. During the takeoff climb, about 500 to 600 ft above ground level, the engine starting "sputtering" and continued to run but the airplane did not maintain altitude. The choke was off, and the pilot applied various throttle settings to no avail. The pilot performed a forced landing to a field, and the airplane came to rest inverted. Postaccident examination of the airplane's fuel system was satisfactory and did not reveal any contamination. Further, examination of the engine revealed that the engine's left and right carburetor float bowls contained clean fuel. During a test run of the engine, the engine was started and run at idle before running up to power. The postaccident engine examination and test run did not reveal any evidence of preimpact malfunctions or failures that would have precluded normal operation. Weather conditions at the time of the accident were conducive to the accumulation of serious carburetor icing at glide power settings; however, the airplane was fueled with automotive fuel, which may have a different carburetor icing range than that depicted in Federal Aviation Administration guidance for aviation fuel. Additionally, the airplane was at takeoff power and not glide/idle power when the power loss occurred. Thus, it is not likely that the formation of serious carburetor icing occurred. A reason for the loss of engine power could not be determined.
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 (partial) during initial climb defining event
- Off-field or emergency landing during landing
- Nose over/nose down during landing
- Collision with terrain or object (not controlled flight into terrain) during landing
The NTSB's findings
- cause Not determined › Not determined › (general) › (general) › Unknown/Not determined
Pilot
- Certificate: sport pilot
- Ratings: single-engine land
- Flight time: 303 hours in all; 254 in this make and model; 10 in the last 90 days; 2 in the last 30 days; 254 as pilot in command
- Medical certificate: Sport Pilot
- Seat: left
- Injury: minor injuries
Pilot-Rated Passenger
- Certificate: private
- Ratings: single-engine land
- Flight time: 150 hours in all; 0 in this make and model
- Last flight review: January 1, 1980
- Medical certificate: Unknown
- Seat: rgt
- Injury: minor injuries
The aircraft
- Airframe total time: 543 hours
- Last inspection: condition inspection, September 14, 2014; 30 hours since
- Maximum gross weight: 1,320 lb
- Seats: 2
- Landing gear: fixed
- Engine: Rotax 912 ULS (piston); 543 hours total
The flight
- Departed from: 2K9 Haskell OK at 5:58 pm
- Destination: H68 Wagoner OK
- Flight plan: not recorded
- Runway 17, 3,710 ft by 30 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 150° at 3 knots
- Visibility: 10 statute miles
- Sky: scat at 4,700 ft
- Temperature: 88°F (31°C), dew point 70°F (21°C)
- Altimeter: 30.00 inHg
- Observation at 5:55 pm from KOKM, 17 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 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.
Other NTSB records under N535CT the same tail number, which may have belonged to a different aircraft at the time
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.