Narrative:

We were on final approach to land in mia; ILS 9 approach in VMC. During the arrival we had basically flown radar vectors in lieu of the arrival to navigate around thunderstorms and isolated cells in the area. Weather and visibility was clear from base leg to final and on the arrival corridor. At approximately 1;400 ft MSL; I verified airspeed and called for flaps 30. As the first officer began to move the flap handle from 25 to 30; we experienced a sudden increase of airspeed which quickly/eventually ended up to be an increase of 30 KTS. Upon noting this; the first officer moved the flap lever back to the 25 position and then up to the 15 degree position. I continued flying the aircraft on the glideslope with adjustments to pitch and power. After the airspeed decreased from a high of 180-185 KTS; we attempted to extend the flaps back to 25. Although the handle moved; the flap indicator remained at 15. There were no signs of a split or skew. The first officer moved the ground proximity flap inhibit switch to inhibit as per the QRH and we increased the bug speed. I continued flying the approach at flaps 15 to a normal landing. After clearing all runways; we raised the flaps and they retracted normally.

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Original NASA ASRS Text

Title: B737-800 flight crew experiences stuck flaps during approach when the flap lever is first selected from 25 to 30 then quickly retracted to 25 then 15 as a wind gust threatens to overspeed the flaps when the flaps cannot be extended; bug speeds are adjusted and a flaps 15 landing ensues. Flaps retract normally after landing.

Narrative: We were on final approach to land in MIA; ILS 9 approach in VMC. During the arrival we had basically flown radar vectors in lieu of the arrival to navigate around thunderstorms and isolated cells in the area. Weather and visibility was clear from base leg to final and on the arrival corridor. At approximately 1;400 FT MSL; I verified airspeed and called for flaps 30. As the First Officer began to move the flap handle from 25 to 30; we experienced a sudden increase of airspeed which quickly/eventually ended up to be an increase of 30 KTS. Upon noting this; the First Officer moved the flap lever back to the 25 position and then up to the 15 degree position. I continued flying the aircraft on the glideslope with adjustments to pitch and power. After the airspeed decreased from a high of 180-185 KTS; we attempted to extend the flaps back to 25. Although the handle moved; the flap indicator remained at 15. There were no signs of a split or skew. The First Officer moved the Ground Proximity Flap Inhibit Switch to Inhibit as per the QRH and we increased the bug speed. I continued flying the approach at flaps 15 to a normal landing. After clearing all runways; we raised the flaps and they retracted normally.

Data retrieved from NASA's ASRS site as of July 2013 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.