prop puzzle

[ghoti]

I have two props for my Gymallo. Both size 9 by 4.7. The orange one by GWS and black by (Im not sure) APC.

Flight Performance is dramaticly different. Thrust, climb rate, glide performance, are all much better with the black one. You have any idea why?
Happy landings, Bill

[Brandano]

Because everything looks better in black, the performance too. How does having a different prop affect the gliding performance? Does the orange one have a significantly larger blade chord?

[JetPlaneFlyer]

It’s not unusual for performance to be quite different between props of the same size and stated pitch. They may use different airfoil profiles, different blade shapes and different twist along their length. Also the stated pitch is not always an accurate reflection of the true pitch.

Like Brandano I would struggle to see how glide would be much affected though unless the orange one has huge 'paddle like' blades or it is weight is significantly different?

just use the black one!

Steve

[Brandano]

one major difference I expect to see between a black prop and a brightly coloured one is that the black prop may have fiberglass or carbon fibers included in its resin and be more rigid as a consequence. This would mean that it would keep its shape better at high RPM, and might result in better (or at least different) performance even if the props were to have the exact same shape. In any case, there's way too many variables, finding the perfect prop is still a sort of black magic.