Narrative:

Flight from sfo to sjc. I was performing PNF duties. My first officer was flying. We were approximately 160 KIAS and my first officer called for 20 degrees flaps. I selected them, but because the flap selector switch was worn, the flaps went to 50 degrees, exceeding the aircraft limitations. Upon discovery, I immediately retracted the flaps to the appropriate setting. We landed at sjc without further incident. On the ground, I determined the flap selector switch had not malfunctioned but was merely worn. I proceeded on the next leg of the trip which was a maintenance base where the flap selector switch was replaced. Neither my company nor the FAA has given me direction concerning appropriate action with worn parts, only malfunctioning parts.

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Original NASA ASRS Text

Title: CAPT OF AN LTT ACR ACFT INADVERTENTLY SET THE WING FLAPS TO THE WRONG SETTING DUE TO A WORN FLAP SETTING SELECTOR RESULTING IN EXCEEDING THE ACFT FLAP SETTING SPD LIMITATION FOR THE SETTING GIVEN.

Narrative: FLT FROM SFO TO SJC. I WAS PERFORMING PNF DUTIES. MY FO WAS FLYING. WE WERE APPROX 160 KIAS AND MY FO CALLED FOR 20 DEGS FLAPS. I SELECTED THEM, BUT BECAUSE THE FLAP SELECTOR SWITCH WAS WORN, THE FLAPS WENT TO 50 DEGS, EXCEEDING THE ACFT LIMITATIONS. UPON DISCOVERY, I IMMEDIATELY RETRACTED THE FLAPS TO THE APPROPRIATE SETTING. WE LANDED AT SJC WITHOUT FURTHER INCIDENT. ON THE GND, I DETERMINED THE FLAP SELECTOR SWITCH HAD NOT MALFUNCTIONED BUT WAS MERELY WORN. I PROCEEDED ON THE NEXT LEG OF THE TRIP WHICH WAS A MAINT BASE WHERE THE FLAP SELECTOR SWITCH WAS REPLACED. NEITHER MY COMPANY NOR THE FAA HAS GIVEN ME DIRECTION CONCERNING APPROPRIATE ACTION WITH WORN PARTS, ONLY MALFUNCTIONING PARTS.

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.