Narrative:

Cleared by approach control from 10000' to 5000', later cleared to 3000'. Clearance was copied and repeated back 'we're 5000' headed for 3000''. VFR conditions above the cloud deck; visibility 10 plus mi. On course heading at 3000' was in direct line with tower intending through cloud deck. Maintained 3400' and turned left to give tower clearance. About this time approach controller came back and said I had descended past assigned altitude of 4000', and to climb and maintain 4000'. In solid IFR this may have ended differently. Despite the copy and readback an error was made. Everyone needs to listen better.

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Original NASA ASRS Text

Title: IFR SMA PLT BELIEVES HE HAS BEEN CLEARED TO 3000' BY TYS APCH CTLR, READS BACK SAME, DESCENDS AND ENCOUNTERS OBSTACLE.

Narrative: CLRED BY APCH CTL FROM 10000' TO 5000', LATER CLRED TO 3000'. CLRNC WAS COPIED AND REPEATED BACK 'WE'RE 5000' HEADED FOR 3000''. VFR CONDITIONS ABOVE THE CLOUD DECK; VIS 10 PLUS MI. ON COURSE HDG AT 3000' WAS IN DIRECT LINE WITH TWR INTENDING THROUGH CLOUD DECK. MAINTAINED 3400' AND TURNED L TO GIVE TWR CLRNC. ABOUT THIS TIME APCH CTLR CAME BACK AND SAID I HAD DSNDED PAST ASSIGNED ALT OF 4000', AND TO CLB AND MAINTAIN 4000'. IN SOLID IFR THIS MAY HAVE ENDED DIFFERENTLY. DESPITE THE COPY AND READBACK AN ERROR WAS MADE. EVERYONE NEEDS TO LISTEN BETTER.

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.