Amateur-built SONEX accident near Wellington, Florida, February 17, 2014
On February 17, 2014 at about 5:50 pm local time, a 2007 amateur-built SONEX, registered N732SX, was destroyed in an accident during initial climb near Wellington, Florida (Wellington Aero Club 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 pilot's failure to maintain adequate airspeed following a partial loss of engine power during initial climb, which led to the airplane exceeding its critical angle of attack and experiencing an aerodynamic stall. Contributing to the accident was the pilot's improper repair of a stripped spark plug hole, which led to a partial loss of engine power during initial climb.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 17, 2014 · about 5:50 pm local time
- Place
- Wellington, Florida · Wellington Aero Club · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built SONEX, built 2007
- Registration
- N732SX · no longer on the register · serial 732
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The airplane had just departed the airport; one witness reported that during the initial climb the engine "sputtered," and another reported that it "backfired." The pilot then made a steep turn back toward the airport, but the airplane stalled and spiraled to the ground. The airplane was equipped with an electronic flight instrument system that recorded numerous engine and flight parameters. Review of the downloaded data revealed that, initially, the engine was operating normally and within design parameters. However, toward the end of the recorded data, the No. 1 cylinder head and exhaust gas temperatures had begun to decrease while the other cylinder temperature parameters remained fairly constant. The engine data then recorded a decrease in engine rpm followed by a steep 180-degree turn toward the airport. A witness who assisted the pilot with the airplane's oil change 2 days earlier stated that the pilot had cross-threaded a spark plug in the No. 1 cylinder and attempted a helicoil repair. During examination after the accident, the No. 1 sparkplug was easily removed by hand. This was likely the cause of the power loss that preceded the pilot's attempt to return to the airport. The pilot's steep, 180-degree turn exceeded the airplane's critical angle of attack, which resulted in a stall at low altitude and collision with terrain. A review of the pilot's toxicology revealed that even though he tested positive for antidepressants, they were not a factor in the accident.
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
- Aircraft maintenance event during prior to flight
- Loss of engine power (partial) during initial climb
- Loss of control in flight during initial climb defining event
- Collision with terrain or object (not controlled flight into terrain) during uncontrolled descent
The NTSB's findings
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Airspeed › Not attained/maintained
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Angle of attack › Not attained/maintained
- cause Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot
- factor Personnel issues › Task performance › Maintenance › Repair › Pilot
- factor Aircraft › Aircraft power plant › Ignition system › Spark plugs/igniters › Incorrect service/maintenance
Pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 13,300 hours in all; 400 in this make and model; 400 in the last 90 days
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: left
- Injury: fatal
The aircraft
- Last inspection: inspection type not recorded
- Maximum gross weight: 1,100 lb
- Seats: 2
- Landing gear: fixed
- Engine: Volkswagon AeroVee (piston); 0 hours total
The flight
- Departed from: FD38 Wellington FL at 5:50 pm
- Destination: FD38 Wellington FL
- Flight plan: none
- Runway 15, 4,000 ft by 100 ft
Weather at the time
- Light: daylight
- Wind: at 6 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 4,300 ft
- Temperature: 70°F (21°C), dew point 52°F (11°C)
- Altimeter: 30.19 inHg
- Observation at 5:53 pm from PBI, 10 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.