Narrative:

Going under the 2500 ft ring (outer) of cmh and realized I had not turned on transponder. I do not often use it since I fly VFR only and normally avoid class C rings, and had forgotten to turn it on.

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Original NASA ASRS Text

Title: PVT PLT OF AN RV4 SMA SEL ACFT FAILED TO TURN ON HIS XPONDER WHILE TRAVERSING UNDER CLASS C AIRSPACE.

Narrative: GOING UNDER THE 2500 FT RING (OUTER) OF CMH AND REALIZED I HAD NOT TURNED ON XPONDER. I DO NOT OFTEN USE IT SINCE I FLY VFR ONLY AND NORMALLY AVOID CLASS C RINGS, AND HAD FORGOTTEN TO TURN IT ON.

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.