Narrative:

I was PF, cleared to descend to 3500 ft. Captain and I made all company calls and followed procedures. For some reason I had 3000 ft in my mind. I descended to approximately 3200 ft. Altitude alert sounded and I immediately corrected to 3500 ft. No response from ATC.

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Original NASA ASRS Text

Title: FO OF DC9 OVERSHOT ASSIGNED ALT DURING RADAR VECTOR DSCNT AND RETURNED TO ASSIGNED IMMEDIATELY WITH NO COMMENT FROM APCH CTL.

Narrative: I WAS PF, CLRED TO DSND TO 3500 FT. CAPT AND I MADE ALL COMPANY CALLS AND FOLLOWED PROCS. FOR SOME REASON I HAD 3000 FT IN MY MIND. I DSNDED TO APPROX 3200 FT. ALT ALERT SOUNDED AND I IMMEDIATELY CORRECTED TO 3500 FT. NO RESPONSE FROM ATC.

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.