Narrative:

We were first cleared for ILS runway 21L at dtw. Captain, myself was PF with autoplt and autothrottles engaged. Descending through 3800 ft, we were cleared for a visual approach. First officer then turned altitude alerter to go around altitude of 4000 ft. Aircraft started to climb. I disconnected the autoplt and autothrottles. Frequency change may have been given at this time. On short final I asked first officer to confirm landing clearance. We were still on approach frequency. I then executed a go around.

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Original NASA ASRS Text

Title: FLC OF AN MLG ON WRONG FREQ SHORT FINAL RESULTING IN A GAR.

Narrative: WE WERE FIRST CLRED FOR ILS RWY 21L AT DTW. CAPT, MYSELF WAS PF WITH AUTOPLT AND AUTOTHROTTLES ENGAGED. DSNDING THROUGH 3800 FT, WE WERE CLRED FOR A VISUAL APCH. FO THEN TURNED ALT ALERTER TO GAR ALT OF 4000 FT. ACFT STARTED TO CLB. I DISCONNECTED THE AUTOPLT AND AUTOTHROTTLES. FREQ CHANGE MAY HAVE BEEN GIVEN AT THIS TIME. ON SHORT FINAL I ASKED FO TO CONFIRM LNDG CLRNC. WE WERE STILL ON APCH FREQ. I THEN EXECUTED A GAR.

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.