Narrative:

Takeoff and climb out were standard. All checklists were performed per SOP. The flight was filed for FL310. ATC assigned us FL260 as a final. The airspeed was set at 320 KIAS to make up time lost due to flow control. At cruise, about 40 mi prior to descent, the captain began the landing brief. While briefing the descent and landing, the throttles began to retard and the plane started a descent. Seconds later, the plane began to buffet. The captain disengaged the autoplt and retarded the throttles while looking for the problem. The first officer made a statement about wake turbulence. The captain then noticed a leading edge flap transit amber light and called for flaps up. Flaps retracted normally. The flaps had extended to 1 degree and the flap handle was in the flaps 1 degree detent. The first officer does not think he hit the handle. The captain and the first officer did not see or hear the handle move. The aircraft lost less than 100 ft of altitude prior to recovery. The flight continued to oak for a normal landing.

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Original NASA ASRS Text

Title: A B737-300 AT FL260 EXPERIENCED BUFFETING AT 320 KIAS WHEN IT WAS DISCOVERED THE FLAP HANDLE WAS IN THE 1 UNIT DETENT. CAUSE OF FLAP HANDLE IN 1 UNIT DETENT UNKNOWN.

Narrative: TKOF AND CLBOUT WERE STANDARD. ALL CHKLISTS WERE PERFORMED PER SOP. THE FLT WAS FILED FOR FL310. ATC ASSIGNED US FL260 AS A FINAL. THE AIRSPD WAS SET AT 320 KIAS TO MAKE UP TIME LOST DUE TO FLOW CTL. AT CRUISE, ABOUT 40 MI PRIOR TO DSCNT, THE CAPT BEGAN THE LNDG BRIEF. WHILE BRIEFING THE DSCNT AND LNDG, THE THROTTLES BEGAN TO RETARD AND THE PLANE STARTED A DSCNT. SECONDS LATER, THE PLANE BEGAN TO BUFFET. THE CAPT DISENGAGED THE AUTOPLT AND RETARDED THE THROTTLES WHILE LOOKING FOR THE PROB. THE FO MADE A STATEMENT ABOUT WAKE TURB. THE CAPT THEN NOTICED A LEADING EDGE FLAP TRANSIT AMBER LIGHT AND CALLED FOR FLAPS UP. FLAPS RETRACTED NORMALLY. THE FLAPS HAD EXTENDED TO 1 DEG AND THE FLAP HANDLE WAS IN THE FLAPS 1 DEG DETENT. THE FO DOES NOT THINK HE HIT THE HANDLE. THE CAPT AND THE FO DID NOT SEE OR HEAR THE HANDLE MOVE. THE ACFT LOST LESS THAN 100 FT OF ALT PRIOR TO RECOVERY. THE FLT CONTINUED TO OAK FOR A NORMAL LNDG.

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.