Narrative:

Several passenger noticed an abnormality with the left wing. My observation from the cabin found that sheet metal from the upper surface of the outboard slat appeared to be flexing upward several inches above the wing surface. From the cockpit, all indications were normal and the aircraft flew normally. I conferred with dispatch and maintenance: based on my description of the problem and our proximity to dtw, both felt it safe to continue. A normal approach and landing were performed in dtw. Postflt inspection at the gate found that the outermost attachment point on the outboard left slat had failed, causing the slat to flex upward near the wingtip in-flight. At the gate, the inboard end of the slat had retracted normally while the outboard end had jammed in a mostly extended position. In retrospect, I should have declared an emergency in-flight, diverted to a nearby airport, and performed a no-slat landing. I could not see from the cabin how serious the problem was, but I knew something was wrong with the outboard left slat. The potential for disaster should there have been further structural failure or detachment of the slat in-flight or during slat extension was high. Supplemental information from acn 482000: we were climbing to cruise altitude when the flight attendant came into the cockpit to report that a passenger had noticed something on the wing. We had 2 uniformed company DC9 crew members on board jump seating. The flight attendant asked both of these crew members to inspect the wing. They did, and said they saw nothing. The flight attendant saw something on the wing and felt that the 2 crew members didn't take her seriously. I went back and saw something on the wing. I informed my captain, and he went back and also saw something. It looked like part of the slat was sticking up at the wingtip. There were no unusual indications in the cockpit. We landed at our destination after conferring with maintenance control.

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Original NASA ASRS Text

Title: DC9 CREW HAD LEADING EDGE SLAT ATTACHMENT FAILURE IN ZOB CLASS A AIRSPACE.

Narrative: SEVERAL PAX NOTICED AN ABNORMALITY WITH THE L WING. MY OBSERVATION FROM THE CABIN FOUND THAT SHEET METAL FROM THE UPPER SURFACE OF THE OUTBOARD SLAT APPEARED TO BE FLEXING UPWARD SEVERAL INCHES ABOVE THE WING SURFACE. FROM THE COCKPIT, ALL INDICATIONS WERE NORMAL AND THE ACFT FLEW NORMALLY. I CONFERRED WITH DISPATCH AND MAINT: BASED ON MY DESCRIPTION OF THE PROB AND OUR PROX TO DTW, BOTH FELT IT SAFE TO CONTINUE. A NORMAL APCH AND LNDG WERE PERFORMED IN DTW. POSTFLT INSPECTION AT THE GATE FOUND THAT THE OUTERMOST ATTACHMENT POINT ON THE OUTBOARD L SLAT HAD FAILED, CAUSING THE SLAT TO FLEX UPWARD NEAR THE WINGTIP INFLT. AT THE GATE, THE INBOARD END OF THE SLAT HAD RETRACTED NORMALLY WHILE THE OUTBOARD END HAD JAMMED IN A MOSTLY EXTENDED POS. IN RETROSPECT, I SHOULD HAVE DECLARED AN EMER INFLT, DIVERTED TO A NEARBY ARPT, AND PERFORMED A NO-SLAT LNDG. I COULD NOT SEE FROM THE CABIN HOW SERIOUS THE PROB WAS, BUT I KNEW SOMETHING WAS WRONG WITH THE OUTBOARD L SLAT. THE POTENTIAL FOR DISASTER SHOULD THERE HAVE BEEN FURTHER STRUCTURAL FAILURE OR DETACHMENT OF THE SLAT INFLT OR DURING SLAT EXTENSION WAS HIGH. SUPPLEMENTAL INFO FROM ACN 482000: WE WERE CLBING TO CRUISE ALT WHEN THE FLT ATTENDANT CAME INTO THE COCKPIT TO RPT THAT A PAX HAD NOTICED SOMETHING ON THE WING. WE HAD 2 UNIFORMED COMPANY DC9 CREW MEMBERS ON BOARD JUMP SEATING. THE FLT ATTENDANT ASKED BOTH OF THESE CREW MEMBERS TO INSPECT THE WING. THEY DID, AND SAID THEY SAW NOTHING. THE FLT ATTENDANT SAW SOMETHING ON THE WING AND FELT THAT THE 2 CREW MEMBERS DIDN'T TAKE HER SERIOUSLY. I WENT BACK AND SAW SOMETHING ON THE WING. I INFORMED MY CAPT, AND HE WENT BACK AND ALSO SAW SOMETHING. IT LOOKED LIKE PART OF THE SLAT WAS STICKING UP AT THE WINGTIP. THERE WERE NO UNUSUAL INDICATIONS IN THE COCKPIT. WE LANDED AT OUR DEST AFTER CONFERRING WITH MAINT CTL.

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.