Narrative:

On climb out ZZZ we felt what I described as going over a small pot hole. Soon after I got a call from a flight attendant at door 3R. He said that he heard a bang under the floor at his location. I told him that we felt something as well and we would check things out and get back to him. After reaching a safe altitude; the relief pilot went back to the location to talk to the F/as and see if there was anything unusual. I proceeded to call dispatch and [maintenance]. I advised them what we heard and felt and we came to the conclusion that we had a possible cargo shift. [Maintenance] called load planning and they said we had 3 pallets in the aft cargo compartment. We had no other indications in the cockpit and the first officer that went back called and said he could not feel anything unusual back there. We all came to the conclusion that it was safe to proceed. Remainder of flight was normal and we landed in ZZZZ without further incident. After deplaning; we went outside to check the cargo and that is when we saw that we had lost an aerodynamic panel below and in front of door 3R.

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Original NASA ASRS Text

Title: B777 flight crew reported hearing a bang from the under-floor area. They continued to their international destination where they found a fuselage panel missing from the fuselage in the vicinity of door 3R.

Narrative: On climb out ZZZ we felt what I described as going over a small pot hole. Soon after I got a call from a flight attendant at door 3R. He said that he heard a bang under the floor at his location. I told him that we felt something as well and we would check things out and get back to him. After reaching a safe altitude; the relief pilot went back to the location to talk to the F/As and see if there was anything unusual. I proceeded to call Dispatch and [Maintenance]. I advised them what we heard and felt and we came to the conclusion that we had a possible cargo shift. [Maintenance] called load planning and they said we had 3 pallets in the aft cargo compartment. We had no other indications in the cockpit and the F/O that went back called and said he could not feel anything unusual back there. We all came to the conclusion that it was safe to proceed. Remainder of flight was normal and we landed in ZZZZ without further incident. After deplaning; we went outside to check the cargo and that is when we saw that we had lost an aerodynamic panel below and in front of door 3R.

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.