Narrative:

I was tasked a periodic service check with a removal and replacement of fuel control unit of the APU on [the] aircraft. After completion of ps check; I removed and replaced APU fuel control unit referring [to] amm. While performing operation and leak check; I observed flames emitting from APU exhaust. I called to cockpit to notify of fire; then proceeded to extinguish fire and call to notify fire department and lead. Subsequent to fire being extinguished; an inspection was performed on APU compartment and APU exhaust with no damage noted.

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Original NASA ASRS Text

Title: Air Carrier Maintenance Technician reported that while performing an operational check on the APU; flames started coming out of the exhaust.

Narrative: I was tasked a Periodic Service Check with a removal and replacement of Fuel Control Unit of the APU on [the] aircraft. After completion of PS Check; I removed and replaced APU Fuel Control Unit referring [to] AMM. While performing Operation and Leak Check; I observed flames emitting from APU exhaust. I called to cockpit to notify of fire; then proceeded to extinguish fire and call to notify fire department and Lead. Subsequent to fire being extinguished; an inspection was performed on APU compartment and APU exhaust with no damage noted.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.