Narrative:

Cruising at FL390; we heard two loud bangs and felt the airplane yaw momentarily. We then got a number 1 engine low oil pressure warning. I then retarded the thrust lever on the number 1 engine. The oil pressure fluctuated between 28 and 32 psi so the warning would go out momentarily but mostly stayed on. All other engine indications looked normal. The airspeed was starting to decay so I pulled up the driftdown page and told the captain we needed to start down to FL270. He declared an emergency with ATC and they cleared us down. I then started a drift down descent. The captain then ran the low oil pressure QRH that led to the engine shutdown checklist. We then shut down the number 1 engine. It looked like ZZZ was the closest airport so we started a diversion there and I continued the descent. The captain notified dispatch; maintenance control; the flight attendants; and passengers of what was happening. He then ran the single engine approach and landing checklist and prepared for a flaps 15 landing. By that time we were on approach to [the airport]; he then took the aircraft and landed uneventfully and taxied to the gate.

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Original NASA ASRS Text

Title: A B737 experienced a Number 1 Engine failure due to low oil pressure. The crew declared an emergency and diverted.

Narrative: Cruising at FL390; we heard two loud bangs and felt the airplane yaw momentarily. We then got a Number 1 Engine low oil pressure warning. I then retarded the thrust lever on the Number 1 Engine. The oil pressure fluctuated between 28 and 32 PSI so the warning would go out momentarily but mostly stayed on. All other engine indications looked normal. The airspeed was starting to decay so I pulled up the driftdown page and told the Captain we needed to start down to FL270. He declared an emergency with ATC and they cleared us down. I then started a drift down descent. The Captain then ran the low oil pressure QRH that led to the Engine Shutdown Checklist. We then shut down the Number 1 Engine. It looked like ZZZ was the closest airport so we started a diversion there and I continued the descent. The Captain notified Dispatch; Maintenance Control; the flight attendants; and passengers of what was happening. He then ran the Single Engine Approach and Landing checklist and prepared for a flaps 15 landing. By that time we were on approach to [the airport]; he then took the aircraft and landed uneventfully and taxied to the gate.

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.