the pitch of the propeller is the distance that the propeller rotates once, which is the theoretical pitch. However, since the included angle between the propeller blade and the shaft changes with the radius, the pitch also changes, and the pitch is unequal at different positions in the radial direction of the blade. Generally, the pitch at 3/4 of the propeller radius is taken as the pitch of the whole propeller.

Generally speaking, the pitch of a propeller is just like the theoretical distance when a screw is screwed in one turn.