Airborne Windsport Edge XT-912-L accident near Captain Cook, Hawaii, April 21, 2010
On April 21, 2010 at about 7:36 pm local time, a Airborne Windsport Edge XT-912-L (weight-shift aircraft), registered N34TH, was substantially damaged in an accident during maneuvering near Captain Cook, Hawaii. It was an instructional flight under general aviation rules (Part 91). 2 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s intentional in-flight maneuvers that exceeded the structural limits of the aircraft, which resulted in structural failure of the wings.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 21, 2010 · about 7:36 pm local time
- Place
- Captain Cook, Hawaii · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Airborne Windsport Edge XT-912-L
- Registration
- N34TH · no longer on the register · serial XT-912-0335
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The flight was an introductory flight lesson in a weight-shift-controlled aircraft. Witnesses reported that they observed the aircraft maneuver over the ocean and approach a 450-foot cliff at a 45-degree angle. As the aircraft came close to the cliff, it banked steeply away and rolled inverted. Witnesses reported hearing a loud “pop” and the wings folded around the fuselage (pod). The aircraft descended in a spiraling corkscrew-like manner before impacting the water. The aircraft immediately sank and was never recovered. The pilot likely exceeded the manufacturer’s operating limitations for the aircraft, which specifies a maximum pitch limit of 45 degrees and a maximum bank angle of 60 degrees. Positive flight load factors are limited to 4G and negative loads are prohibited; flight loads between positive 1G and 0G should be avoided. The pilot’s operating handbook cautioned that negative G maneuvers can never be conducted safely and stated that these maneuvers put the aircraft outside of the pilot’s control.
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 control in flight during maneuvering defining event
The NTSB's findings
- cause Aircraft › Aircraft structures › Fuselage › Wing attach fittings (on fus) › Capability exceeded
- cause Personnel issues › Action/decision › Action › Incorrect action selection › Pilot
Pilot
- Certificate: private, sport pilot
- Ratings: single-engine land; instructor: sport pilot
- Flight time: 375 hours in all
- Last flight review: January 18, 2009
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: rear
- Injury: fatal
The aircraft
- Airframe total time: 100 hours
- Last inspection: condition inspection, April 9, 2010
- Maximum gross weight: 992 lb
- Seats: 2
- Landing gear: fixed
- Engine: Rotax 912 UL (piston); 0 hours total
The flight
- Departed from: KOA Kailua Kona HI at 7:16 pm
- Destination: KOA Kailua Kona HI
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 270° at 6 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 77°F (25°C), dew point 61°F (16°C)
- Altimeter: 30.09 inHg
- Observation at 6:53 pm from KOA, 17 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 2 |
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.