Narrative:

Immediately following takeoff we heard a loud knocking/slapping noise outside the 4L door. We checked around the door and inside the lavatory and could not find anything that looked out of the ordinary. There seemed to be no air leak but the noise was very unusual and very loud. The cockpit was called and they could hear the noise over the phone. We returned to dfw, mechanics opened the door to find a red twill strap attached to a hook on the forward inside frame of the door. Approximately 8 inches of the 3 ft strap was left outside the aircraft door and was slapping against the fuselage. There was no apparent damage so the strap was removed and we left again.

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Original NASA ASRS Text

Title: AN MD11, IMMEDIATELY AFTER TKOF, RETURNED TO THE FIELD DUE TO A STRAP HANGING OUT OF DOOR 4L.

Narrative: IMMEDIATELY FOLLOWING TKOF WE HEARD A LOUD KNOCKING/SLAPPING NOISE OUTSIDE THE 4L DOOR. WE CHKED AROUND THE DOOR AND INSIDE THE LAVATORY AND COULD NOT FIND ANYTHING THAT LOOKED OUT OF THE ORDINARY. THERE SEEMED TO BE NO AIR LEAK BUT THE NOISE WAS VERY UNUSUAL AND VERY LOUD. THE COCKPIT WAS CALLED AND THEY COULD HEAR THE NOISE OVER THE PHONE. WE RETURNED TO DFW, MECHS OPENED THE DOOR TO FIND A RED TWILL STRAP ATTACHED TO A HOOK ON THE FORWARD INSIDE FRAME OF THE DOOR. APPROX 8 INCHES OF THE 3 FT STRAP WAS LEFT OUTSIDE THE ACFT DOOR AND WAS SLAPPING AGAINST THE FUSELAGE. THERE WAS NO APPARENT DAMAGE SO THE STRAP WAS REMOVED AND WE LEFT AGAIN.

Data retrieved from NASA's ASRS site as of July 2007 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.