Accident Overview
On January 17, 2010, at 1506 mountain standard time, a Mooney M20S airplane, registration N782LU, was substantially damaged by fire during taxi for takeoff at Cuchara Valley Airport (07V) in La Veta, Colorado. The private pilot, who was the sole occupant, received minor injuries. The flight was conducted under 14 CFR Part 91 in visual meteorological conditions.
Pilot Account
The pilot reported that just after making a turn during taxi, he heard a “pop” and observed smoke and flames emanating from the engine area. He stopped the airplane, shut down the engine, and evacuated as the fuselage became engulfed in flames. The fire was subsequently extinguished, but the fuselage was mostly consumed.
Damage and Examination
Post-accident examination revealed that the engine compartment remained intact and the engine was still attached to the airframe. The majority of fire damage was concentrated between the engine and the firewall. The rear portion of the engine compartment, particularly around the fuel flow transducer and the aft left lower section, exhibited fire damage. The firewall showed a localized area of high-temperature thermal damage, where the material had turned white, located directly behind the fuel flow transducer.
Fuel Flow Transducer Analysis
The fuel flow transducer (Mooney Part #880030) was examined by the NTSB Materials Laboratory, along with sections of fuel line from its inlet and outlet sides. The associated fuel lines were standard steel-braided sleeved rubber hose. The inlet connector was an AN-816 straight pipe-to-tube adapter, and the outlet connector was a MS 51508 45-degree pipe-to-tube elbow with a male pipe end. X-rays of the transducer with fuel lines attached revealed no obvious internal defects. During disassembly, the outlet fuel line was found to be loose at the crimp of the fuel line connector where it attached to the outlet elbow. Upon removal, approximately 0.75 inch of interior rubber hose was missing from beneath the steel braid, along with a portion of steel braid approximately 0.25 inch wide and 0.25 inch long. The remaining interior rubber hose appeared to have thermal damage, but the section where the steel braid was missing did not show thermal damage. The cause of the missing steel braid was not determined.