NTSB Factual Report

On October 28, 2008, about 1105 mountain daylight time, an amateur built Silfvast Starduster Too experimental biplane, N78DS, was destroyed when it impacted terrain while performing aerobatic maneuvers near Cedar Fort, Utah. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91. The private pilot and his commercial pilot rated passenger were killed. Visual meteorological conditions prevailed and no flight plan was filed for the local personal flight. The flight originated from Salt Lake City Municipal 2 Airport, West Jordan, Utah at an unknown time.

Multiple witnesses in the vicinity of the accident site reported observing the accident airplane performing a series of aerobatic maneuvers at a low altitude. The airplane was observed in a "flat spin" about 1,000 feet above ground level until impacting the ground where a post-impact fire ensued. One witness stated that he heard the engine running until the airplane impacted the ground.

Examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed that the airplane came to rest inverted within an open field and was consumed by fire. All major components of the airplane were located at the accident site. The primary flight controls of the airplane remained attached to their respective mounts. Control continuity was established from the cockpit controls to all primary flight controls.

The Utah State Medical Examiner's office conducted an autopsy on the pilot on October 29, 2008. The medical examiner determined that the cause of death was "total body blunt force injuries."

The FAA's Civil Aeromedical Institute (CAMI) in Oklahoma City, Oklahoma, performed toxicology tests on the pilot. According to CAMI's report, carbon monoxide, cyanide, volatiles, and drugs were tested, and had negative results except for an unspecified amount of Naproxen detected in the liver.

The Utah State Medical Examiner's office conducted an autopsy on the pilot-rated passenger on October 29, 2008. The medical examiner determined that the cause of death was "total body blunt force injuries."

The FAA's Civil Aeromedical Institute (CAMI) in Oklahoma City, Oklahoma, performed toxicology tests on the pilot-rated passenger. According to CAMI's report, carbon monoxide, cyanide, volatiles, and drugs were tested, and had negative results.

NTSB Probable Cause

The pilot's failure to maintain an adequate airspeed and/or angle of attack to avoid a stall/spin during an aerobatic maneuver.