Narrative:

The captain and I were operating aircraft X. On taxi out; we received several reports from the flight attendants; ramp personnel via ATC and a company crew behind us that the aircraft had produced a flame and two loud bangs. We received no indication of a fire or malfunction in the cockpit. It took a moment to put the information together and into context as we initially thought it was the #2 engine; but it ended up being the #1 engine. At first there was some confusion from outside sources as I was talking to the captain; ATC and the company crew. We ran the engine fire checklist and got the engine shutdown. Ground control dispatched a vehicle and they confirmed there was no fire. We taxied back to the gate and deplaned.

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Original NASA ASRS Text

Title: B737-700 flight crew reported being notified during taxi of a flaming engine due to oil leaking into the tailpipe.

Narrative: The Captain and I were operating Aircraft X. On taxi out; we received several reports from the flight attendants; ramp personnel via ATC and a company crew behind us that the aircraft had produced a flame and two loud bangs. We received no indication of a fire or malfunction in the cockpit. It took a moment to put the information together and into context as we initially thought it was the #2 engine; but it ended up being the #1 engine. At first there was some confusion from outside sources as I was talking to the Captain; ATC and the company crew. We ran the Engine Fire Checklist and got the engine shutdown. Ground Control dispatched a vehicle and they confirmed there was no fire. We taxied back to the gate and deplaned.

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.