Narrative:

Climbing through 22;000 feet the aircraft suddenly yawed left with a faint thud noise. The thrust stopped abruptly. My first thought was the yaw damper kicked off or was malfunctioning. Then when we realized the engine quit. I thought maybe it flamed out because of no perceived damage. The captain immediately took control. I was inclined to run the engine failure/shutdown checklist leading to a relight as there was no overheat; no fire indication; no vibration; and N1 and N2 were turning. We also had a deferred APU which complicated things just a bit. The captain elected to run engine fire severe damage/separation. I facilitated with memory items (very fresh in my head having just got out of training) and the running of the QRH leading into the single engine landing checklist; while handling the radios with ATC and coordinating our return to ZZZ after we determined it was our closest suitable airport. Landed uneventfully.

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Original NASA ASRS Text

Title: A B737-300 engine failed during climb so after running the QRH; an emergency was declared and the flight returned to the departure airport for an uneventful landing.

Narrative: Climbing through 22;000 feet the aircraft suddenly yawed left with a faint thud noise. The thrust stopped abruptly. My first thought was the Yaw Damper kicked off or was malfunctioning. Then when we realized the engine quit. I thought maybe it flamed out because of no perceived damage. The Captain immediately took control. I was inclined to run the Engine Failure/Shutdown Checklist leading to a relight as there was no overheat; no fire indication; no vibration; and N1 and N2 were turning. We also had a deferred APU which complicated things just a bit. The Captain elected to run Engine Fire Severe Damage/Separation. I facilitated with memory items (very fresh in my head having just got out of training) and the running of the QRH leading into the Single Engine Landing Checklist; while handling the radios with ATC and coordinating our return to ZZZ after we determined it was our closest suitable airport. Landed uneventfully.

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.