Spicewood, TX, USA
N922TP
HUSTON CHARLES D PITTS S-12
The airplane was on departure when the engine started sputtering and lost power. The pilot turned toward the runway and landed beside the runway in the dirt, substantially damaging the airplane. Postaccident examination revealed that the fuel flow sensor, which was located upstream of the fuel flow filter, was clogged with an unidentified substance and there was particulate matter in the fuel lines. The source of the substances could not be determined. The experimental airplane manufacturer installed the fuel flow sensor upstream of the fuel flow filter as depicted on a fuel flow schematic, provided for information only, by the airplane airframe kit manufacturer. The installation instructions for the fuel flow sensor indicated the fuel flow sensor should be installed downstream of a fuel filter.
On June 4, 2009, about 2000 central daylight time, a Huston Pitts S-12 homebuilt airplane, N922TP, was substantially damaged during a forced landing following a loss of engine power after takeoff from Spicewood Airport (88R), Spicewood, Texas. The commercial pilot received minor injuries. The personal flight was being conducted under the provisions of Title 14 Code of Federal Regulations Part 91 without a flight plan. The local flight was originating at the time of the accident. Visual meteorological conditions prevailed at the time of the accident. The pilot stated he was flying the 23rd flight in the airplane since it was certified in July, 2008. He was planning on flying a local flight to practice flight characteristics. Prior to flight he "topped off" the fuel tanks. He said preflight and run-up were normal and the fuel checked from the airplane tanks was clean. During climb out from initial takeoff and about 500 feet above the ground (AGL), the master caution light illuminated and the pilot received a "Fuel Pressure" message. The pilot immediately turned to a downwind leg. Soon afterward the engine started sputtering. The pilot turned on the electric fuel boost pump and the engine did not respond. The engine quit when the pilot was approximately abeam midfield, so he turned immediately towards the runway and elected to land in the grass beside the paved runway. During landing the airplane bounced three times before coming to a rest beside the runway. Examination of the airplane showed the engine firewall and both lower wing spars bent. The wing fuel tanks were ruptured and did not contain any fuel. Fuel captured from a fuel line contained small particles of an unidentified substance. The Floscan 201B-6 fuel flow sensor, which was located upstream of the fuel filter, was obstructed with an unidentified substance. The source of the unidentified substance was not located. The airplane was a homebuilt, experimental airplane, manufactured by the pilot. During manufacture the fuel flow sensor was installed upstream of the fuel filter. The pilot told investigators he installed the fuel flow sensor upstream of the fuel filter as depicted on the Pitts Model 12 fuel schematic provided for reference by the airplane airframe kit manufacturer, Jim Kimball Enterprises, Inc. A representative of the airplane airframe kit manufacturer stated the fuel schematic was provided for reference only. He also stated the manufacturer was responsible for determining the location of components per their desires and the installation instructions of each particular component. The notes section of the installation instructions for the Floscan 201B-6 state “The transducer should be mounted downstream of a fuel filter.”
A total loss of engine power due to fuel starvation as a result of the presence of an unidentified contaminant in the fuel system which clogged the fuel flow sensor. Contributing to the accident was the manufacturer’s installation of the fuel flow sensor upstream of the fuel filter and the misleading fuel schematic published by the airplane kit manufacturer.
Source: NTSB Aviation Accident Database
Aviation Accidents App
In-Depth Access to Aviation Accident Reports
