While I was a PPL I was flying a 65hp Aeronca 7AC on a 100 mile xc and was skirting a CB about 15 miles off my R wing, in clear & calm at 1500 AGL. While watching all the activity I noticed the ground looked farther away than I thought right, and noticed the altimeter 2000' and climbing. Sloppy flying!
I retarded power. Still climbing.
Pulled on carb heat. Still climbing.
Did a fast 180 and got the hell out of there!