Just been rading some rigging material, and came across this and wondered how this effects the situation
On average, a propeller loses about 2% efficiency when the inflow of the air to the propeller
disk is not perpendicular to the disk, for angles less than ten degrees, and the loss in efficiency
increases rapidly for greater angles. The overall loss in propulsive efficiency is small
compared to the pitching or yawing moments that are produced, which require trim (drag) to
cancel out.