Narrative:

Upon initiating our descent we experienced a loud rumbling sound--which sounded like a compressor stall--that subsequently turned out to be caused by an unsecured uld [unit load device] container in the main cargo compartment. It was very apparent; with every successive acceleration/deceleration and pitch change in the terminal area; that one of our containers was loose. When we arrived at the ramp following landing we requested that operations have a load supervisor and mechanic meet us at the aircraft. Following shutdown and upon further inspection; the load supervisor advised us that the 2R uld (3;697 pounds) was not secured and that the locks had not been properly positioned. The mechanic later informed me there was no damage to the aircraft.

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Original NASA ASRS Text

Title: Rumbling sounds from the main deck alerted the flight crew of a B767-300 of an unsecured cargo container; which was confirmed by ground crews after landing.

Narrative: Upon initiating our descent we experienced a loud rumbling sound--which sounded like a compressor stall--that subsequently turned out to be caused by an unsecured ULD [Unit Load Device] container in the main cargo compartment. It was very apparent; with every successive acceleration/deceleration and pitch change in the terminal area; that one of our containers was loose. When we arrived at the ramp following landing we requested that Operations have a load supervisor and mechanic meet us at the aircraft. Following shutdown and upon further inspection; the load supervisor advised us that the 2R ULD (3;697 LBS) was not secured and that the locks had not been properly positioned. The mechanic later informed me there was no damage to the aircraft.

Data retrieved from NASA's ASRS site as of April 2012 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.