Narrative:

We were being vectored for runway 13 in visual conditions with some scattered to broken clouds 2000 ft AGL. Coming from the northeast. I had briefed the ILS runway 13 including the 1474 ft tower about 3 miles north of the outer marker approach gave us a descent of 2000 ft. We both heard it, set it, read it back, and pointed to the altitude window. I was configuring, slowing, and looking for the airport. I pointed out the towers at our 1 O'clock position and commented that they had us rather low relative to them. Approach asked us if we had the field in sight, but we were pretty shallow and I could not see it yet. They then asked us to confirm 2500 ft, and altimeter setting. I initiated a climb to 2500 ft smoothly crossing the OM transitioning to a stabilized descent having spotted the airport and being cleared for the visual 1-2 mi outside of the OM on the left base. Co-pilot and I talked about it and are 99% sure that our descent clearance was to 2000 ft. We read back 2000 ft so there was a hearback problem at the least. I should have questioned the altitude assignment sooner as the procedure turn altitude was 2600 ft, but we were being vectored in basically visual conditions with a rather close turn on and were rather busy. I will not only include the LOM crossing altitude in my briefings as I do now, but think of it as relative to vectoring as well as a GS xchk when inbound on the localizer. Things were starting to not feel right and we were watching the obstructions when the controller questioned us. We should have caught it earlier.

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Original NASA ASRS Text

Title: AFTER COPYING AND READING BACK THEIR CLRNC, B737-300 FLT CREW IS ADVISED BY APCH CTLR THAT THEY WERE 500 FT LOWER THAN THE ASSIGNED ALT.

Narrative: WE WERE BEING VECTORED FOR RWY 13 IN VISUAL CONDITIONS WITH SOME SCATTERED TO BROKEN CLOUDS 2000 FT AGL. COMING FROM THE NE. I HAD BRIEFED THE ILS RWY 13 INCLUDING THE 1474 FT TWR ABOUT 3 MILES N OF THE OUTER MARKER APCH GAVE US A DESCENT OF 2000 FT. WE BOTH HEARD IT, SET IT, READ IT BACK, AND POINTED TO THE ALT WINDOW. I WAS CONFIGURING, SLOWING, AND LOOKING FOR THE ARPT. I POINTED OUT THE TWRS AT OUR 1 O'CLOCK POS AND COMMENTED THAT THEY HAD US RATHER LOW RELATIVE TO THEM. APCH ASKED US IF WE HAD THE FIELD IN SIGHT, BUT WE WERE PRETTY SHALLOW AND I COULD NOT SEE IT YET. THEY THEN ASKED US TO CONFIRM 2500 FT, AND ALTIMETER SETTING. I INITIATED A CLB TO 2500 FT SMOOTHLY XING THE OM TRANSITIONING TO A STABILIZED DSCNT HAVING SPOTTED THE ARPT AND BEING CLRED FOR THE VISUAL 1-2 MI OUTSIDE OF THE OM ON THE L BASE. CO-PLT AND I TALKED ABOUT IT AND ARE 99% SURE THAT OUR DSCNT CLRNC WAS TO 2000 FT. WE READ BACK 2000 FT SO THERE WAS A HEARBACK PROB AT THE LEAST. I SHOULD HAVE QUESTIONED THE ALT ASSIGNMENT SOONER AS THE PROC TURN ALT WAS 2600 FT, BUT WE WERE BEING VECTORED IN BASICALLY VISUAL CONDITIONS WITH A RATHER CLOSE TURN ON AND WERE RATHER BUSY. I WILL NOT ONLY INCLUDE THE LOM XING ALT IN MY BRIEFINGS AS I DO NOW, BUT THINK OF IT AS RELATIVE TO VECTORING AS WELL AS A GS XCHK WHEN INBOUND ON THE LOC. THINGS WERE STARTING TO NOT FEEL RIGHT AND WE WERE WATCHING THE OBSTRUCTIONS WHEN THE CTLR QUESTIONED US. WE SHOULD HAVE CAUGHT IT EARLIER.

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.