Narrative:

This event was the classic setup for a potential mishap. We were en route from tallahassee, fl, to atlanta, GA, (ie, short flight) on the last leg of a 4-DAY rotation with a XX45 wake-up in pittsburgh (ie, we were tired). It was the third flight of the day on an airplane with an inoperative autoplt. Both the a and B autoplt were mco'ed inoperative. Everything had been generally uneventful until on the lagrange 7 arrival STAR into atl. The flight was less than 40 mins with a climb to a cruising altitude of FL280. After leveloff we were cleared down FL240. As we approached lgc VOR the captain busied himself with talking to passenger, getting the ATIS, coordinating with the flight attendants about turbulence around atl and sending our company in-range report on the ACARS. He therefore was off of center frequency which left me solo with no autoplt. We were then given a heading of 040 degrees to intercept the lagrange 7 arrival northeast of lagrange, cross tiroe at 13000 ft with an altimeter of 30.31. This is what I wrote down. I spun in the heading and altitude into the flight director and thought it at first odd to cross tiroe at 13000 ft since the STAR calls for 14000 ft at tiroe (expect). As we passed through FL180 we began the descent checklist. By this time I needed to brief up the visual approach to runway 27L backed up by the ILS runway 27L. I gave control of the aircraft to the captain as I briefed up the approach. When I was finished he returned to me aircraft control. As we approached approximately 13300-13200 ft ATC asked us what altitude we were flying. For some reason, I don't remember what, the captain was off the ATC radio so I answered the call. I told ATC we were coming level at 13000 ft assigned. He asked us to climb to 14000 ft. Just as I pushed up the throttles ATC came back and said 13000 ft was ok and to remain there.

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Original NASA ASRS Text

Title: A B737-200 FLC DSNDS THROUGH CLRED ALT IN ZTL, GA, AIRSPACE BECAUSE THE FLC DIDN'T COPY THE PROPER CLRED ALT.

Narrative: THIS EVENT WAS THE CLASSIC SETUP FOR A POTENTIAL MISHAP. WE WERE ENRTE FROM TALLAHASSEE, FL, TO ATLANTA, GA, (IE, SHORT FLT) ON THE LAST LEG OF A 4-DAY ROTATION WITH A XX45 WAKE-UP IN PITTSBURGH (IE, WE WERE TIRED). IT WAS THE THIRD FLT OF THE DAY ON AN AIRPLANE WITH AN INOP AUTOPLT. BOTH THE A AND B AUTOPLT WERE MCO'ED INOP. EVERYTHING HAD BEEN GENERALLY UNEVENTFUL UNTIL ON THE LAGRANGE 7 ARR STAR INTO ATL. THE FLT WAS LESS THAN 40 MINS WITH A CLB TO A CRUISING ALT OF FL280. AFTER LEVELOFF WE WERE CLRED DOWN FL240. AS WE APCHED LGC VOR THE CAPT BUSIED HIMSELF WITH TALKING TO PAX, GETTING THE ATIS, COORDINATING WITH THE FLT ATTENDANTS ABOUT TURB AROUND ATL AND SENDING OUR COMPANY IN-RANGE RPT ON THE ACARS. HE THEREFORE WAS OFF OF CTR FREQ WHICH LEFT ME SOLO WITH NO AUTOPLT. WE WERE THEN GIVEN A HDG OF 040 DEGS TO INTERCEPT THE LAGRANGE 7 ARR NE OF LAGRANGE, CROSS TIROE AT 13000 FT WITH AN ALTIMETER OF 30.31. THIS IS WHAT I WROTE DOWN. I SPUN IN THE HEADING AND ALT INTO THE FLT DIRECTOR AND THOUGHT IT AT FIRST ODD TO CROSS TIROE AT 13000 FT SINCE THE STAR CALLS FOR 14000 FT AT TIROE (EXPECT). AS WE PASSED THROUGH FL180 WE BEGAN THE DSCNT CHKLIST. BY THIS TIME I NEEDED TO BRIEF UP THE VISUAL APCH TO RWY 27L BACKED UP BY THE ILS RWY 27L. I GAVE CTL OF THE ACFT TO THE CAPT AS I BRIEFED UP THE APCH. WHEN I WAS FINISHED HE RETURNED TO ME ACFT CTL. AS WE APCHED APPROX 13300-13200 FT ATC ASKED US WHAT ALT WE WERE FLYING. FOR SOME REASON, I DON'T REMEMBER WHAT, THE CAPT WAS OFF THE ATC RADIO SO I ANSWERED THE CALL. I TOLD ATC WE WERE COMING LEVEL AT 13000 FT ASSIGNED. HE ASKED US TO CLB TO 14000 FT. JUST AS I PUSHED UP THE THROTTLES ATC CAME BACK AND SAID 13000 FT WAS OK AND TO REMAIN THERE.

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.