Narrative:

Clearance for approach, maintain 2500 ft until GS intercept. This is the situation. We had a minor maintenance problem in which we used 40 degree flaps. This is an abnormal procedure. It slowed aircraft faster than expected. We had to descend visually to increase airspeed. Then, with added power, we climbed back to GS intercept altitude which was 2500 ft. +/-400 ft was lost during this time. No incidences occurred with any other aircraft.

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Original NASA ASRS Text

Title: PIC OF A B727 FREIGHTER HAS AN ALTDEV DURING A NIGHT OP WHEN USING 40 DEGS OF FLAPS FOR THE APCH. AN UNEXPECTED SPD DECAY OCCURRED AND THE DELAY IN ADDING PWR CREATED THE ALTDEV.

Narrative: CLRNC FOR APCH, MAINTAIN 2500 FT UNTIL GS INTERCEPT. THIS IS THE SIT. WE HAD A MINOR MAINT PROB IN WHICH WE USED 40 DEG FLAPS. THIS IS AN ABNORMAL PROC. IT SLOWED ACFT FASTER THAN EXPECTED. WE HAD TO DSND VISUALLY TO INCREASE AIRSPD. THEN, WITH ADDED PWR, WE CLBED BACK TO GS INTERCEPT ALT WHICH WAS 2500 FT. +/-400 FT WAS LOST DURING THIS TIME. NO INCIDENCES OCCURRED WITH ANY OTHER ACFT.

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.