Narrative:

I was the [first officer]; pilot flying to ZZZ. I had the first break and left my duty station after passing FL180. (The relief first officer) took over my duties and responsibilities at that point until the conclusion of the event. The event happened prior to zzzzz climbing from FL360 to FL380. I was on break when I heard a loud bang and a strong vibration coming from the left engine. I looked out the window to look for any signs of damage or visual indications of fire. Everything looked normal. The flight attendants came to get my attention and I proceeded back to the flight deck. The affected engine was the left engine and it was back near idle when I entered the cockpit. I began to run the engine limit or surge or stall checklist while the captain and first officer handled the flying and talking on the radios. The engine indications appeared normal but for the excessive vibrations and was left at idle until the final approach segment [back at the departure airport]. ATC was notified by captain; and first officer flew the approach and landing. Landing was uneventful and arff said there nothing out of the ordinary. Thrust reverser worked properly. We taxied back to the gate and shut down normally. The passengers deplaned and we lived to fight another day. After talking to maintenance and seeing the images that they sent to us. It was clear that the nose cone had an area that broke off due to stress fatigue and was ingested into the outer fan section. The acoustic panels and fan blade had noticeable damage.

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Original NASA ASRS Text

Title: B767 flight crew reported a left engine compressor stall during climb.

Narrative: I was the [First Officer]; pilot flying to ZZZ. I had the first break and left my duty station after passing FL180. (The Relief First Officer) took over my duties and responsibilities at that point until the conclusion of the event. The event happened prior to ZZZZZ climbing from FL360 to FL380. I was on break when I heard a loud bang and a strong vibration coming from the left engine. I looked out the window to look for any signs of damage or visual indications of fire. Everything looked normal. The flight attendants came to get my attention and I proceeded back to the flight deck. The affected engine was the left engine and it was back near idle when I entered the cockpit. I began to run the Engine Limit or Surge or Stall Checklist while the Captain and FO handled the flying and talking on the radios. The engine indications appeared normal but for the excessive vibrations and was left at idle until the final approach segment [back at the departure airport]. ATC was notified by Captain; and FO flew the approach and landing. Landing was uneventful and ARFF said there nothing out of the ordinary. Thrust reverser worked properly. We taxied back to the gate and shut down normally. The passengers deplaned and we lived to fight another day. After talking to maintenance and seeing the images that they sent to us. It was clear that the nose cone had an area that broke off due to stress fatigue and was ingested into the outer fan section. The acoustic panels and fan blade had noticeable damage.

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.