Narrative:

Cleared FL310, I (first officer, PNF) was changing from msp to oma charts, made passenger PA, started to check ATIS, and was making en route call to oma operations. I called '2 to go' (2000 ft) and '1 to go' (1000 ft) and resumed my duties. Flight was only 45 mins. I had lots to do! I was also doing (setting ACARS up for level off engine data). I never heard altitude alerter because volume was too low. First time I knew that we overshot was when center called us passing 31400 ft. Captain then did a smooth level off at 31600 ft and returned to FL310. Controller acknowledged our level off, nothing else was said.

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Original NASA ASRS Text

Title: FLC EXCEEDS ASSIGNED ALT 600 FT.

Narrative: CLRED FL310, I (FO, PNF) WAS CHANGING FROM MSP TO OMA CHARTS, MADE PAX PA, STARTED TO CHK ATIS, AND WAS MAKING ENRTE CALL TO OMA OPS. I CALLED '2 TO GO' (2000 FT) AND '1 TO GO' (1000 FT) AND RESUMED MY DUTIES. FLT WAS ONLY 45 MINS. I HAD LOTS TO DO! I WAS ALSO DOING (SETTING ACARS UP FOR LEVEL OFF ENG DATA). I NEVER HEARD ALT ALERTER BECAUSE VOLUME WAS TOO LOW. FIRST TIME I KNEW THAT WE OVERSHOT WAS WHEN CTR CALLED US PASSING 31400 FT. CAPT THEN DID A SMOOTH LEVEL OFF AT 31600 FT AND RETURNED TO FL310. CTLR ACKNOWLEDGED OUR LEVEL OFF, NOTHING ELSE WAS SAID.

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.