Yeah, me too, Bruce. I always try to be careful, and I'm still not sure exactly what I did, because I was reaching in from behind, rather than in front or above and the pressure tap is a couple inches away from the prop. I can only think maybe I bumped the plane with my foot or something, causing it to roll backwards into my finger. I should have made sure the plane was secure and stationary with one hand before reaching down with the other. Like you said, at least it was minor.

-Scott