What happened
While climbing through 10,000 feet, the pilots of the aircraft noticed an abnormal sound coming from the engine. Seconds later, they detected the smell of smoke and observed smoke emanating from the windshield defroster ducts. In response, the pilots initiated an emergency descent.
As power was reduced and the nose was pitched down to begin the descent, the smoke dissipated; however, the engine began running roughly. The crew executed an emergency landing at a non-towered airport and taxied the aircraft to a parking position before shutting down the engine. After exiting the aircraft, the pilots identified external fire damage to the engine cowling, though no active fire was present.
The investigation
Post-incident examination of the engine revealed that the fuel injector line leading to the number 5 cylinder had fractured, which allowed leaking fuel to ignite. Further inspection of the fuel line showed that it had been previously repaired. This specific type of repair is prohibited by a manufacturer's service bulletin. Investigators were unable to determine the identity of the person who performed the repair or when the work was conducted.
Findings
- A fractured fuel injector line caused leaking fuel to ignite.
- The fuel line contained an unauthorized repair that violated a manufacturer's service bulletin.