Accident Overview
On September 22, 2023, about 1446 Pacific daylight time, an unregistered experimental, amateur-built Golden Circle T-Bird II was substantially damaged when it crashed near Arlington, Washington. The noncertificated pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
Witness Observations
A witness standing in front of a hangar at Arlington Municipal Airport observed the airplane complete a series of practice takeoff maneuvers on the west side of the airport, during which the airplane would become momentarily airborne. During the final takeoff maneuver, the airplane lifted off toward the south and turned right, narrowly missing trees before disappearing behind hangars and trees on a northwesterly heading. The airplane reappeared, and the witness reported it “looked like it was going to dive towards the runway” before the left wing separated in flight.
Video footage from the east side of the airport showed the airplane appear above trees on an easterly heading, approaching from the west. It turned south, yawed rapidly, then turned southeast. About 20 seconds later, it turned east, exhibiting erratic pitch and yaw, then turned right toward the northeast, crossed runway 16/34, and continued turning right at a steep bank angle, entering a nose-low attitude. Two seconds later, the left wing separated; the airplane then entered a rapid descent. The engine sound was erratic throughout the video and ceased about 3 seconds after wing separation.
Wreckage Examination
The airplane came to rest inverted in a grass area about 275 ft west of the approach end of runway 16. Several structural tubes were located between the main wreckage and the separated left wing, which came to rest about 400 ft northeast of the main wreckage. Propeller blade fragments were found around the left wing. The right wing fabric was torn and its structural tubes were bent. The vertical stabilizer was crushed; rudder, horizontal stabilizer, and elevator remained undamaged. The engine remained attached to the fuselage, with propeller blades attached to the crankshaft via the hub.
Postaccident examination of the engine revealed no preimpact mechanical anomalies that would have precluded normal operation. Aileron control continuity was traced through multiple separations, all consistent with overload failure.
According to the airplane installation manual, the wings are secured to the fuselage root tube via two spars per wing and four wing struts. The spars connect to the root tube assembly with bolts, washers, and castellated nuts. The forward and aft wing spars remained attached to the root tube assembly with all hardware in place. The right wing spars showed signatures consistent with overload failure at the wing root. The forward left wing spar had been previously repaired: the spar tube was spliced with a sleeve. The sleeve exhibited fracture signatures consistent with overload failure. The aft left wing spar also showed fracture signatures consistent with overload. The airplane maintenance records were not located.
The kit manufacturer stated that they require customers to purchase replacement parts and would not approve a sleeve as a repair on any structure.
Pilot Information
The pilot did not possess an FAA medical certificate or a valid FAA pilot certificate. Logbooks were not recovered to account for total flight experience.
Toxicological Findings
An autopsy conducted by the Snohomish County Medical Examiner listed the cause of death as “blunt traumatic injuries” and manner of death as accident. Postmortem toxicological testing of liver tissue by NMS Labs detected ethanol at 0.95 g/hg, methamphetamine at 16,000 ng/g, amphetamine at 1,500 ng/g, and delta-9-THC, 11-hydroxy-THC, and carboxy-THC. Testing by the FAA Forensic Sciences Laboratory detected methamphetamine, amphetamine, delta-9-THC, 11-hydroxy-THC, carboxy-THC, amitriptyline, and nortriptyline in various tissues. Ethanol was not detected in liver or muscle tissue. Blood was not available for testing.