Narrative:

Air carrier X was descended to 13000' MSL. The aircraft descended to 12000' MSL in a 13000' minimum vectoring altitude. No evasive action needed because of VFR conditions. Both pilot and controller need to be more aware of correct altitude assignment and pay closer attention for instruction and readback.

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Original NASA ASRS Text

Title: ACR X DESCENDED BELOW MVA. SYSTEM ERROR PLT DEVIATION.

Narrative: ACR X WAS DESCENDED TO 13000' MSL. THE ACFT DESCENDED TO 12000' MSL IN A 13000' MINIMUM VECTORING ALT. NO EVASIVE ACTION NEEDED BECAUSE OF VFR CONDITIONS. BOTH PLT AND CTLR NEED TO BE MORE AWARE OF CORRECT ALT ASSIGNMENT AND PAY CLOSER ATTN FOR INSTRUCTION AND READBACK.

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.