Narrative:

Made VFR flight from ZZZ1 to ZZZ2. Upon landing at ZZZ2, the control tower asked me to call the area supervisor for the ZZZ airport class C airspace. Upon calling the supervisor, I was surprised that he told me while en route to ZZZ2 airport my aircraft had traversed the east edge of ZZZ class C airspace. Most of my flying in the area has been under IFR. I was sure that I was east of the class C airspace for ZZZ. I reviewed the VFR charts for the route and realized that I had indeed clipped the edge of the airspace and should have been further east of my position. The class C airspace has been expanded very recently and this required me to fly further east than I thought would be necessary. In the future, I will be sure to obtain 'flight following' when VFR or file and fly under IFR to prevent any inadvertent incursion.

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Original NASA ASRS Text

Title: C172 PLT, DURING VFR FLT, TRANSITS CLASS C AIRSPACE WITHOUT CLRNC.

Narrative: MADE VFR FLT FROM ZZZ1 TO ZZZ2. UPON LNDG AT ZZZ2, THE CTL TWR ASKED ME TO CALL THE AREA SUPVR FOR THE ZZZ ARPT CLASS C AIRSPACE. UPON CALLING THE SUPVR, I WAS SURPRISED THAT HE TOLD ME WHILE ENRTE TO ZZZ2 ARPT MY ACFT HAD TRAVERSED THE E EDGE OF ZZZ CLASS C AIRSPACE. MOST OF MY FLYING IN THE AREA HAS BEEN UNDER IFR. I WAS SURE THAT I WAS E OF THE CLASS C AIRSPACE FOR ZZZ. I REVIEWED THE VFR CHARTS FOR THE RTE AND REALIZED THAT I HAD INDEED CLIPPED THE EDGE OF THE AIRSPACE AND SHOULD HAVE BEEN FURTHER E OF MY POS. THE CLASS C AIRSPACE HAS BEEN EXPANDED VERY RECENTLY AND THIS REQUIRED ME TO FLY FURTHER E THAN I THOUGHT WOULD BE NECESSARY. IN THE FUTURE, I WILL BE SURE TO OBTAIN 'FLT FOLLOWING' WHEN VFR OR FILE AND FLY UNDER IFR TO PREVENT ANY INADVERTENT INCURSION.

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.