Narrative:

On approach we selected flaps 40 at 150 knots. The flaps did not extend past 30 degrees. We selected flaps 30 and landed normally. On the ground; we selected 40 and the flaps extended normally.

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Original NASA ASRS Text

Title: A B737-300 Flight Crew was unable to extend flaps to fourty degrees. Flaps extended normally after landing with flaps thirty.

Narrative: On approach we selected flaps 40 at 150 knots. The flaps did not extend past 30 degrees. We selected flaps 30 and landed normally. On the ground; we selected 40 and the flaps extended normally.

Data retrieved from NASA's ASRS site as of April 2012 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.