Narrative:

First officer was flying. Descending on STAR into stl. Cleared to FL310, I was distracted by flight attendant for a few seconds. When I looked back at instruments, I saw we had descended 700 ft below assigned altitude of FL310. Immediately returned to FL310. Beware of distrs during flight.

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Original NASA ASRS Text

Title: FLC OF AN MLG OVERSHOT DSCNT ALT.

Narrative: FO WAS FLYING. DSNDING ON STAR INTO STL. CLRED TO FL310, I WAS DISTRACTED BY FLT ATTENDANT FOR A FEW SECONDS. WHEN I LOOKED BACK AT INSTS, I SAW WE HAD DSNDED 700 FT BELOW ASSIGNED ALT OF FL310. IMMEDIATELY RETURNED TO FL310. BEWARE OF DISTRS DURING FLT.

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.