Hi all,
     hopefully this is in the right forum here but I am curious to know exactly what propeller washout (beyond normal blade twist) does for any stunt engine.

In short, why reduce the potential thrust available from the very area that should be operating at its maximum?

(I have Googled various sites but can find nothing model related that is of any use and further been part of discussions on this before and came to no real conclusion.)

Thanks.

    Two issues - it probably isn't really washed out. It *measures* that way but if it is cambered, it has an effective pitch that is higher, sometimes MUCH higher, than it measures. In the cases I calculated it, the effective pitch on a prop that measured helical was something like twice the measured pitch. That was a prop with a lot of camber so it's an extreme case, but not all that extreme.

   Issue (or comment, really)  two - go inspect Igor's comments in the other thread about "effiiciency", and why you might want it to be low in level flight. As the airplane slows from maneuvering the thrust distribution changes radically as well as the efficiency. The AoA of the inner sections changes a lot but the q is low, and the tips don't change very much but the q is very high. That alone tends to explain why the tip pitch seems to have dramatic effect on the performance during and out of a corner.

    Brett