BoatBanter.com - View Single Post - Angle of prop shaft

On 05 Jun 2004 18:24:40 GMT, (JAXAshby) wrote:

steve, bone up on "P-torque" or "P-thrust" or more accurately "asymetrical
thrust". It is a common problem for aircraft with "conventional" landing gear
(meaning two wheels up front and one on the tail), and has been fully
understood since the early days of WWII.

That's only a factor when you're moving quick enough for the angle of
attack to be different for different parts of the prop if it's tilted
relative to the flow of the fluid. In the case we're talking about here
it's not a factor at all because we're talking about throwing it in
reverse and when the boat is not moving there is prop walk. If the prop
is not moving relative to the fluid, the angle of attack is the same all
around no matter what direction it's facing.

Steve