Accident Details
On October 28, 2008, at approximately 1105 mountain daylight time, an amateur-built Silfvast Starduster Too experimental biplane, registered as N78DS, was destroyed when it struck the ground while conducting aerobatic maneuvers near Cedar Fort, Utah. The flight was operated under 14 Code of Federal Regulations Part 91 by the private pilot, who also owned the aircraft. The pilot and his passenger, a commercial pilot, were fatally injured. Visual meteorological conditions prevailed; no flight plan had been filed for the local personal flight. The airplane had departed from Salt Lake City Municipal 2 Airport in West Jordan, Utah, at an unknown time.
Witness Observations
Multiple witnesses in the vicinity reported seeing the biplane performing a series of aerobatic maneuvers at low altitude. They observed the aircraft enter a “flat spin” approximately 1,000 feet above ground level, which continued until impact. A post-impact fire ensued. One witness stated hearing the engine running until the moment of ground contact.
Wreckage Examination
An FAA inspector examined the wreckage at the site. The airplane came to rest inverted in an open field and was entirely consumed by fire. All major structural components were accounted for at the scene. The primary flight controls remained attached to their respective mounts, and control continuity was established from the cockpit to all primary flight control surfaces.
Autopsy and Toxicology
Autopsies conducted on October 29, 2008, by the Utah State Medical Examiner's Office determined that both the pilot and passenger died from “total body blunt force injuries.” Toxicological tests performed by the FAA's Civil Aeromedical Institute (CAMI) were negative for carbon monoxide, cyanide, volatiles, and drugs, except for the detection of an unspecified amount of Naproxen in the pilot's liver. The passenger's toxicology results were entirely negative.
Conclusion
No probable cause was determined from the investigation as presented in the source material.