Narrative:

Climbing out of hsv, was cleared by ZTL to climb to 14000 ft. Our readback confirmed 14000 ft. At 14500 ft, ATC questioned our altitude and at the same time the TCASII called 'traffic -- traffic.' we responded that we were climbing to 15000 ft, as set in the altitude alert window. ATC advised that we were cleared to 14000 ft so we immediately descended to 14000 ft. The workload imposed on a 2 man crew during departure/arrival on a short segment contributed to the misinterp of the altitude alert window. Additionally, turning and pulling the altitude alert knob has the potential of mis-setting the altitude (especially when you are busy). In this instance, the altitude was set at 15000 ft. Supplemental information from acn 209976: ZTL cleared us to climb to what I thought was 15000 ft. I was flying the aircraft, with the captain handling the radios. I saw 15000 ft in my FMA. After establishing a climb at 380 KTS on the arrival, I armed the autoplt. The captain told me to monitor the center while he addressed the passenger. He took back the radios as we were passing 14500 ft for 15000.

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Original NASA ASRS Text

Title: FLC OF ACR MLG FLIES THROUGH CLRED ALT OF 14000 FT BECAUSE FO THOUGHT THEY WERE CLRED TO 15000 WHEN IN FACT, THE ALT ALERTER HAD SIMPLY BEEN MIS-SET. TCASII ALERTED CREW TO POTENTIAL CONFLICT AT 14500 FT.

Narrative: CLBING OUT OF HSV, WAS CLRED BY ZTL TO CLB TO 14000 FT. OUR READBACK CONFIRMED 14000 FT. AT 14500 FT, ATC QUESTIONED OUR ALT AND AT THE SAME TIME THE TCASII CALLED 'TFC -- TFC.' WE RESPONDED THAT WE WERE CLBING TO 15000 FT, AS SET IN THE ALT ALERT WINDOW. ATC ADVISED THAT WE WERE CLRED TO 14000 FT SO WE IMMEDIATELY DSNDED TO 14000 FT. THE WORKLOAD IMPOSED ON A 2 MAN CREW DURING DEP/ARR ON A SHORT SEGMENT CONTRIBUTED TO THE MISINTERP OF THE ALT ALERT WINDOW. ADDITIONALLY, TURNING AND PULLING THE ALT ALERT KNOB HAS THE POTENTIAL OF MIS-SETTING THE ALT (ESPECIALLY WHEN YOU ARE BUSY). IN THIS INSTANCE, THE ALT WAS SET AT 15000 FT. SUPPLEMENTAL INFO FROM ACN 209976: ZTL CLRED US TO CLB TO WHAT I THOUGHT WAS 15000 FT. I WAS FLYING THE ACFT, WITH THE CAPT HANDLING THE RADIOS. I SAW 15000 FT IN MY FMA. AFTER ESTABLISHING A CLB AT 380 KTS ON THE ARR, I ARMED THE AUTOPLT. THE CAPT TOLD ME TO MONITOR THE CTR WHILE HE ADDRESSED THE PAX. HE TOOK BACK THE RADIOS AS WE WERE PASSING 14500 FT FOR 15000.

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.