Narrative:

Called cvg approach 17 mi sse at 6500 ft for flight following. Flown this area often in the past, did not realize it went from class C airspace to class B airspace. I did have current charts, just always knew it as class C airspace.

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Original NASA ASRS Text

Title: PA31 FLC ARE ADVISED BY CVG THAT THEY HAVE PENETRATED CLASS B AIRSPACE WITHOUT A CLRNC WHEN FLC CALLS FOR FLT FOLLOWING.

Narrative: CALLED CVG APCH 17 MI SSE AT 6500 FT FOR FLT FOLLOWING. FLOWN THIS AREA OFTEN IN THE PAST, DID NOT REALIZE IT WENT FROM CLASS C AIRSPACE TO CLASS B AIRSPACE. I DID HAVE CURRENT CHARTS, JUST ALWAYS KNEW IT AS CLASS C AIRSPACE.

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.