The Incident
On 23 September 2013, a Socata TB10 Tobago, registration G-FAIR, was on a private flight approaching Rayne Hall Farm in Braintree, Essex. During the late downwind leg, the pilot sensed the engine running unevenly and missing beats. Carburetor heat had been applied, leading the pilot to suspect carburetor ice. As a precaution, he executed a high approach.
Landing and Fire
The landing was successful, but as the aircraft came to a stop on the runway, the engine ceased running and smoke emerged from the upper right side of the engine cowling. The passenger exited the aircraft and spotted a small fire beneath the cowling. He quickly extinguished it using the onboard fire extinguisher.
Post-Incident Inspection
After the fire was extinguished, the cowlings were removed, revealing extensive soot and fire damage. When the electrical fuel pump was switched on, fuel poured from the underside of the carburetor.
Maintenance Findings
Two days later, the maintenance organisation removed the carburetor and conducted tests in their workshop. They were unable to reproduce the fuel leak, and a strip inspection found no defects. They believed that a transient sticking of the float may have caused overfuelling of the carburetor, leading to the fire.