Narrative:

VFR flight from I67 to mwo at 3500 ft. I thought that the bottom of the control zone area was 4000 ft in the area in which I was flying. I was told later by ATC at cvg that a jet on approach at 4000 ft had to change course. I took a closer look and studied the sectional chart more closely and found my mistake.

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Original NASA ASRS Text

Title: APPEARS THIS EXTREMELY LOW TIME PVT PLT MAY HAVE VIOLATED THE NEW CLASS B AIRSPACE AT CVG. APPARENTLY, HE WAS OBLIVIOUS TO HIS UNAUTH PENETRATION OF THE AIRSPACE AND WAS SOMEHOW NOTIFIED, AFTER HIS FLT, BY CVG THAT AN AIRLINER HAD TO TAKE EVASIVE ACTION.

Narrative: VFR FLT FROM I67 TO MWO AT 3500 FT. I THOUGHT THAT THE BOTTOM OF THE CTL ZONE AREA WAS 4000 FT IN THE AREA IN WHICH I WAS FLYING. I WAS TOLD LATER BY ATC AT CVG THAT A JET ON APCH AT 4000 FT HAD TO CHANGE COURSE. I TOOK A CLOSER LOOK AND STUDIED THE SECTIONAL CHART MORE CLOSELY AND FOUND MY MISTAKE.

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.