WPR09LA026

NTSB accident investigation · Silfvast Starduster TOO · Cedar Fort, UT · October 28, 2008

Accident · FatalLimited investigationFinal report
Date
October 28, 2008, 11:05 local (17:05 UTC)
Place
Cedar Fort, UT
Injuries
2 fatal
Damage
Destroyed
Phase of flight
Maneuvering
Aircraft
N78DSSilfvast Starduster TOO
Defining event
Maneuvering-aerobatics: Aerodynamic stall/spin
Weather
Visual (VMC) · Day
Status
Completed · report May 6, 2009
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration
FAA report
20081028850789A
Case key
69356

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

The NTSB’s determination of the probable cause, and any contributing factors.

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

Findings · 3

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings.

Analysis

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 what the witnesses described as a "flat spin" about 1,000 feet above ground level that continued until ground impact. One witness stated that he heard the engine running until the airplane impacted the ground. The airplane was consumed in a postimpact ground fire and all major components of the airplane were located at the accident site. No anomalies were noted with the airplane flight control system during an examination of the wreckage.

Factual narrative

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.

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident.

Aircraft

Registration
N78DS
Reported as
Silfvast Starduster TOO
Category
Airplane, amateur-built
Serial number
DAS-1
Airframe hours
272.18
Engine
Lycoming AEIO-360, 180 horsepower, reciprocating
Damage
Destroyed
Flight
Personal · Part 91
Operator
Silfvast David A
Registered owner
Silfvast David A
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Continuous airworthiness · May 1, 2008
Departed
U42 · West Jordan, UT
Flight plan
Unknown
Airport
UT10 · Cedar Valley Airport

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
62
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Last flight review
October 27, 2008
Toxicology
Performed
Flight hours
439 total · 3 in the last 90 days · 3 in the last 30 days · 1 in the last 24 hours
Role
Pilot
Age
71
Injuries
Fatal
Certificates
Commercial, Airline transport
Airplane ratings
Single-engine land, Multi-engine sea, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, With waivers/limitations
Toxicology
Performed

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
15 statute miles
Lowest ceiling
None
Temperature
52 °F, dew point 36 °F
Altimeter
30.47 inHg
Observed at
PVU, 23 nm away

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.