Narrative:

Flight left the gate at PM39 local, headed for runway 26 for takeoff. Shortly after takeoff, while in a climbing right turn, the first officer, who was flying, reported to me some vibrations in the control column while passing. Through 2500 ft the handling of the airplane was not affected negatively, however, the vibrations could be felt all the way through the airplane. We leveled off and slowed down the airplane to 160 KTS. I looked toward the left engine and propeller and noticed a piece of metal on the outboard of the left wing flapping up and down on top of the wing. We proceeded to return to iah for landing. The approach and landing were uneventful and normal. No emergency was declared since there was never any doubt in the outcome of a safe landing. The post-flight inspection revealed that the inspection panel between the left aileron and the wing had 12 retaining screws missing and 2 stripped. Therefore, allowing about 2 ft of that panel to be loose and flap up and down on top of the wing. The area is not visible during the preflight inspection due to the height of the wing. The airplane had just come out of maintenance, and it was the first flight since the airplane had come out of the hangar. This poses some serious questions about maintenance procedures.

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Original NASA ASRS Text

Title: FLC OF ACR LTT ACFT EXPERIENCED AN ACFT VIBRATION CAUSED BY A LOOSE WING PANEL AND RETURNED TO BASE.

Narrative: FLT LEFT THE GATE AT PM39 LCL, HEADED FOR RWY 26 FOR TKOF. SHORTLY AFTER TKOF, WHILE IN A CLBING R TURN, THE FO, WHO WAS FLYING, RPTED TO ME SOME VIBRATIONS IN THE CTL COLUMN WHILE PASSING. THROUGH 2500 FT THE HANDLING OF THE AIRPLANE WAS NOT AFFECTED NEGATIVELY, HOWEVER, THE VIBRATIONS COULD BE FELT ALL THE WAY THROUGH THE AIRPLANE. WE LEVELED OFF AND SLOWED DOWN THE AIRPLANE TO 160 KTS. I LOOKED TOWARD THE L ENG AND PROP AND NOTICED A PIECE OF METAL ON THE OUTBOARD OF THE L WING FLAPPING UP AND DOWN ON TOP OF THE WING. WE PROCEEDED TO RETURN TO IAH FOR LNDG. THE APCH AND LNDG WERE UNEVENTFUL AND NORMAL. NO EMER WAS DECLARED SINCE THERE WAS NEVER ANY DOUBT IN THE OUTCOME OF A SAFE LNDG. THE POST-FLT INSPECTION REVEALED THAT THE INSPECTION PANEL BTWN THE L AILERON AND THE WING HAD 12 RETAINING SCREWS MISSING AND 2 STRIPPED. THEREFORE, ALLOWING ABOUT 2 FT OF THAT PANEL TO BE LOOSE AND FLAP UP AND DOWN ON TOP OF THE WING. THE AREA IS NOT VISIBLE DURING THE PREFLT INSPECTION DUE TO THE HEIGHT OF THE WING. THE AIRPLANE HAD JUST COME OUT OF MAINT, AND IT WAS THE FIRST FLT SINCE THE AIRPLANE HAD COME OUT OF THE HANGAR. THIS POSES SOME SERIOUS QUESTIONS ABOUT MAINT PROCS.

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.