On: Why Paper Jams Persist

[aidenn0]

In reality usually neither side is flat.

[travisjungroth → aidenn0]

A flat bottom wing gives you nice stall and landing characteristics. Very small, 2-4 seat, trainer airplanes have them. (Cessna 150, J3 Cub)

[aidenn0 → travisjungroth]

I wouldn't call the Cessna 150 flat, as it has visible lower-camber, but you are right about the J3 Cub; it's super flat on the bottom.