Narrative:

Pushback and engine start were uneventful; the ground crew had returned to the gate and we had completed the before taxi checklist as normal. When we started to taxi; we got an amber 'engine control' light on the overhead panel. About 10 seconds later; as the first officer was reviewing the QRH; a flight attendant started hitting the pilot call button continuously. I stopped what I was doing and answered the call. He said the number one engine was on fire and there were 3-7 foot flames coming out the back of the engine. Although we had no indication of a fire in the cockpit I reached down to shut the engine off and motor it; but it had already auto shut down itself. We had no indications of high egt. I asked ground control to send fire equipment out to inspect the aircraft. The flight attendants then started pounding on the cockpit door nonstop and ringing our call button at the same time. I answered the intercom and he said we were still on fire so I pulled the fire handle and discharged one fire bottle. Ground stated later they saw flames around our engine as we taxied out. I advised the passengers that the fire with number one engine was under control; that the fire department was going to check us out before we returned to the gate and to remain seated and buckled up. We had no outside observers during this event. Our information came from the flight attendants and passengers only. We returned to the gate and swapped airplanes. Maintenance came out and looked the engine over. They stated it was some type of fuel leak and not a tail pipe fire since the engine had started and stabilized at idle for three-four minutes before we added power.

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Original NASA ASRS Text

Title: As they began their taxi from the gate the flight crew of a B737-700 received frantic alerts from the flight attendants of flames emanating from the exhaust of the left engine. Investigation determined the engine control light had illuminated and the engine had performed an auto shut down. Emergency equipment was dispatched and the flight returned to the gate.

Narrative: Pushback and engine start were uneventful; the ground crew had returned to the gate and we had completed the Before Taxi Checklist as normal. When we started to taxi; we got an amber 'ENG CONTROL' light on the overhead panel. About 10 seconds later; as the First Officer was reviewing the QRH; a Flight Attendant started hitting the Pilot call button continuously. I stopped what I was doing and answered the call. He said the number one engine was on fire and there were 3-7 foot flames coming out the back of the engine. Although we had no indication of a fire in the cockpit I reached down to shut the engine off and motor it; but it had already auto shut down itself. We had no indications of high EGT. I asked Ground Control to send fire equipment out to inspect the aircraft. The flight attendants then started pounding on the cockpit door nonstop and ringing our call button at the same time. I answered the intercom and he said we were still on fire so I pulled the fire handle and discharged one fire bottle. Ground stated later they saw flames around our engine as we taxied out. I advised the passengers that the fire with number one engine was under control; that the Fire Department was going to check us out before we returned to the gate and to remain seated and buckled up. We had no outside observers during this event. Our information came from the flight attendants and passengers only. We returned to the gate and swapped airplanes. Maintenance came out and looked the engine over. They stated it was some type of fuel leak and not a tail pipe fire since the engine had started and stabilized at idle for three-four minutes before we added power.

Data retrieved from NASA's ASRS site as of July 2013 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.