I just started flying a H9 Twist with an ASP 40 engine in it. My last plane was a trainer with the same engine in it, and i always ran either a 10-6 or an 11-6 prop on it. after reading some of the forums here, it seems a lot of people use 11.25-3.75 props for .46 size engines...

now to my question.
could someone explain how the larger prop effects the thrust characteristics, and is there a particular prop you would recommend for my ASP 40 (if it helps, one of the regulars at my field flew my trainer with that engine and swore to me it had as much power as a .46, i cant tell though, since it is the only engine i have ever owned)

thanks
-BJ

The reason for 3d hat people like big diameter and low pitch is because it provides better accelaration which you need for 3D, and I think also better low down thrust

correct me if Im wrong anyone but thats what I heard

Shahid

[:-]

more thrust, less speed, you'll find you will climb on less throttle, but won't be able to go very fast. It's like driving in first gear, more accerleration, less speed.

thanks for the info guys, i just found another topic in this forum that addressed the same thing (dont know how i missed it last night). it sounds like 12.25 - 3.75 is the way to go for good low end acceleration.
thanks again
-BJ

wrinklhyp,

A 12.25 x 3.75 may be too much prop for the ASP 40. I like the APC 11.5 x 4 for the .46, and an APC 11 x 4 for the .40's.