Narrative:

About 40 mi nne of acy (my destination airport) I was cleared to descend from 6000 ft MSL to 4000 ft MSL. I was also told to expect landing on runway 13 with a left base entry. I mistook this to mean that I should descend for landing and continued my descent to 3400 ft. At this time the controller requested my altitude and cleared me to descend to 3000 ft. There was no other traffic in the area at this time to conflict with.

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Original NASA ASRS Text

Title: PLT OF SMA ON DSCNT MISINTERPRETS HIS CLRNC AND DSNDS BELOW ASSIGNED ALT.

Narrative: ABOUT 40 MI NNE OF ACY (MY DEST ARPT) I WAS CLRED TO DSND FROM 6000 FT MSL TO 4000 FT MSL. I WAS ALSO TOLD TO EXPECT LNDG ON RWY 13 WITH A L BASE ENTRY. I MISTOOK THIS TO MEAN THAT I SHOULD DSND FOR LNDG AND CONTINUED MY DSCNT TO 3400 FT. AT THIS TIME THE CTLR REQUESTED MY ALT AND CLRED ME TO DSND TO 3000 FT. THERE WAS NO OTHER TFC IN THE AREA AT THIS TIME TO CONFLICT WITH.

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.