AUGUSTINE DAVID L SONEX near Burnet, TX — 2009-11-14
- Date
- 2009-11-14
- Location
- Burnet, TX, USA
- Airport
- KBMQ
- Aircraft
- AUGUSTINE DAVID L SONEX
- Registration
- N10DA
- Category
- Airplane
- Highest injury
- Fatal
- Fatalities
- 1
- Phase of flight
- Descent
Probable cause
The pilot’s failure to maintain aircraft control, resulting in an aerodynamic stall. Contributing to the accident was the loss of engine power due to a clogged fuel screen that resulted in fuel starvation caused by the builder's inappropriate use of a fuel tank sealant in a plastic tank.
Contributing factors
Contributing to the accident was the loss of engine power due to a clogged fuel screen that resulted in fuel starvation caused by the builder's inappropriate use of a fuel tank sealant in a plastic tank.
NTSB narrative
According to several witnesses, the pilot radioed that he was experiencing a loss of engine power and was attempting a forced landing. Witnesses who saw the airplane reported that during the forced landing attempt the nose of airplane dropped and the airplane subsequently impacted terrain in a nose-low attitude. An examination of the flight controls and airframe structure revealed no preaccident anomalies that would have prevented the pilot from maintaining aircraft control. An examination of the engine and fuel system revealed a white substance inside the main fuel tank which had clogged the fuel screen. Laboratory examination of this substance revealed that it was polyurethane. The sealant used to seal the fuel tank contained polyurethane designed to be used to bond the sealant to a metal tank. The airframe builder added this sealant to the accident airplane's plastic (polyethylene) tank when he encountered a leak within the fuel system at the fuel fitting. An examination of the remaining engine and systems revealed no anomalies.
Analysis
- Primary failure mode
- Fuel management
- First missed decision gate
- Pilot could have opted to land at KBMQ instead of attempting to return to K88R.
NTSB coding
Evidence available
- Photos
- 14 docket documents
Docket documents14
- Release of Aircraft Wreckage, NTSB Form 6120.15form
- Sonex Fuel Tank Installation and Warranty Information Rev Bform
- Sonex Fuel Tank Installation and Warranty Information Rev Cform
- Statement of Party Representatives to NTSB Investigationinterview
- Witness Statementinterview
- Jabiru USA Carburetor Examination - CEN10LA050other
- POR 15 Fuel Tank Sealerother
- Photograph 01 - Main Wreckagephotos
- Photograph 02 - Empennagephotos
- Photograph 03 - Cabin and Instrument Panelphotos
- Photograph 04 - Fuel Tank Substancephotos
- Photograph 05 - Main Fuel Tank Finger Screenphotos
- Materials Laboratory 15 - Factual Report 10013report
- Toxicological Reportreport
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