Narrative:

Distraction during descent and descended 400 ft below leveloff altitude. Immediately returned to assigned altitude FL240.

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Original NASA ASRS Text

Title: FO OF A DC9-30 OVERSHOT ALT ON DSCNT DUE TO DISTR AND IMMEDIATELY CORRECTED BACK TO ASSIGNED ALT.

Narrative: DISTR DURING DSCNT AND DSNDED 400 FT BELOW LEVELOFF ALT. IMMEDIATELY RETURNED TO ASSIGNED ALT FL240.

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.