Narrative:

During our initial approach I had planned on a visual approach to runway 1, which was the runway ATIS said was in use. After reviewing my approach charts I had determined that I would remain at an altitude higher than what we normally would be for runway 25 and circle to the left. We were cleared to descend to 11000 ft and then 10000 ft. After being level at 10000 ft for about 3 mins, we were cleared for a visual approach to runway 25. This caught me totally unprepared. We tuned in runway 25 ILS and realized I was well above the GS at 300 KTS. I extended the spoilers and began descending when suddenly I realized I was at 9300 ft, and not 10300 ft. For some reason I thought I was at 11000 ft instead of 10000 ft. I immediately reduced my speed to 250 KTS, then came to the big rush to lower the gear and reduce speed to allow me to extend the flaps to 30 degrees, the final flap setting. With the power at idle, I intercepted the GS at 1100 ft AGL, then added thrust and stabilized the approach at 1000 ft, the min altitude required by company policy to have the aircraft stabilized. Throughout all this, an air carrier operations inspector was observing from the jump seat. I should have planned for a possible visual approach to runway 25, straight in, and reduced my speed accordingly. I could not be flexible enough because of inadequate preplanning. Another factor was even though I observed 10000 ft on the altimeter, I was thinking 11000 ft. The air carrier inspector obviously was a distraction also. I guess I had become complacent without realizing this. In the future I will definitely be more alert or situationally aware.

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Original NASA ASRS Text

Title: ACR LGT SPD DEV EXCEEDED 250 KTS BELOW 10000 FT WITH AN ACI OBSERVING.

Narrative: DURING OUR INITIAL APCH I HAD PLANNED ON A VISUAL APCH TO RWY 1, WHICH WAS THE RWY ATIS SAID WAS IN USE. AFTER REVIEWING MY APCH CHARTS I HAD DETERMINED THAT I WOULD REMAIN AT AN ALT HIGHER THAN WHAT WE NORMALLY WOULD BE FOR RWY 25 AND CIRCLE TO THE L. WE WERE CLRED TO DSND TO 11000 FT AND THEN 10000 FT. AFTER BEING LEVEL AT 10000 FT FOR ABOUT 3 MINS, WE WERE CLRED FOR A VISUAL APCH TO RWY 25. THIS CAUGHT ME TOTALLY UNPREPARED. WE TUNED IN RWY 25 ILS AND REALIZED I WAS WELL ABOVE THE GS AT 300 KTS. I EXTENDED THE SPOILERS AND BEGAN DSNDING WHEN SUDDENLY I REALIZED I WAS AT 9300 FT, AND NOT 10300 FT. FOR SOME REASON I THOUGHT I WAS AT 11000 FT INSTEAD OF 10000 FT. I IMMEDIATELY REDUCED MY SPD TO 250 KTS, THEN CAME TO THE BIG RUSH TO LOWER THE GEAR AND REDUCE SPD TO ALLOW ME TO EXTEND THE FLAPS TO 30 DEGS, THE FINAL FLAP SETTING. WITH THE PWR AT IDLE, I INTERCEPTED THE GS AT 1100 FT AGL, THEN ADDED THRUST AND STABILIZED THE APCH AT 1000 FT, THE MIN ALT REQUIRED BY COMPANY POLICY TO HAVE THE ACFT STABILIZED. THROUGHOUT ALL THIS, AN ACR OPS INSPECTOR WAS OBSERVING FROM THE JUMP SEAT. I SHOULD HAVE PLANNED FOR A POSSIBLE VISUAL APCH TO RWY 25, STRAIGHT IN, AND REDUCED MY SPD ACCORDINGLY. I COULD NOT BE FLEXIBLE ENOUGH BECAUSE OF INADEQUATE PREPLANNING. ANOTHER FACTOR WAS EVEN THOUGH I OBSERVED 10000 FT ON THE ALTIMETER, I WAS THINKING 11000 FT. THE ACR INSPECTOR OBVIOUSLY WAS A DISTR ALSO. I GUESS I HAD BECOME COMPLACENT WITHOUT REALIZING THIS. IN THE FUTURE I WILL DEFINITELY BE MORE ALERT OR SITUATIONALLY AWARE.

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.