# NTSB WPR09LA026: Silfvast Starduster TOO, N78DS, Cedar Fort, UT, October 28, 2008 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: October 28, 2008, 11:05 local (17:05 UTC) - Place: Cedar Fort, UT - Coordinates: 40.357223, -112.017776 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.3572&lon=-112.0178&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-aerobatics: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: Fatal - Injuries: 2 fatal - Status: Completed, report May 6, 2009 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 69356 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR09LA026 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/69356/pdf - Page: https://openairdocs.org/ntsb/WPR09LA026 ## 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. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause) - [Performance/control parameters: angle of attack](https://openairdocs.org/ntsb-findings/01062042): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause) ## 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 best describes what happened. - [Maneuvering-aerobatics: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - [Maneuvering-aerobatics: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) ## Aircraft - Registration: [N78DS](https://openairdocs.org/deregistered/N78DS-2012-09-27), registration cancelled 2012-09-27, S/N DAS-1, built 1984 (OpenAirDocs) - Reported make and model: SILFVAST STARDUSTER TOO - Registry model: [Silfvast STARDUSTER TOO](https://openairdocs.org/model/silfvast-starduster-too) (registry code 8660362) (OpenAirDocs) - Registry engine: [Lycoming AEIO-360 series](https://openairdocs.org/engine/lycoming-aeio-360-series) (registry code 41522, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: DAS-1 - Airframe hours: 272.18 - Engines: 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 ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 62; injuries: fatal; 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 - Pilot; age 71; injuries: fatal; 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 (OpenAirDocs). - [Accident 20081028850789A](https://openairdocs.org/incident/20081028850789A), Oct 28, 2008: Silfva STARDUSTERTO, Cedar Fort, UT, Destroyed, 2 fatal. (-23) Aircraft was observed by people on the ground performing acrobatics when it entered a tight spin and impacted the ground. Aircraft found on its back and… From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.