Wile E Coyote

I am nearly done with my CMP Mosquito ARF build. I started running in the 2 x .40 RMX 2 strokes on Sunday. I am trying to find out the correct prop size to use. The recommended props for the motors are 10x6. My problem is when I put the correct spinners on, 3 1/2" in diameter, there is just about no prop blade showing. Can someone help please?

aerowoof

most of the thrust of the props is generated by the tips any way so you should be fine with a 10-6,if you try a 11-5 you may not have enough speed to fly the plane.

Straight and Level

Equivalent thrust..... the dimeter of the prop squared multiply by the pitch... 10 x 10 x 6 = 600 11 x 11 x 5 = 605 looks like its just about a match

Pa-18cub150

Hi Straight and Level

Is your Equivalent thrust formula the same for three blade props, or do you multiply the diameter by the power of three?

Flying freak

please explain this formula what do you mean by the diamter squared and multipleyd by the pitch

wouldnt (pie r ^2) make more sence because now you ahve the area of the disk multiplyed by the prop


10 x 6
3.14x 10
=31.4^2
=985.96

multiply by pitch (6) =5915.76

11x 5
3.14x 11
=34.54^2
=1193 x 5
= 5965

Wouldnt this make more sence? i dnt understnd hwo you can calculat circles / disk without the use of pie (not i didnt use "full" pie but rath 3.14)


Although we do get to similair difference proportinally iguess both work....

Steven

skull1971

APC 12.25 X 3.75, its a big funfly prop that works real good on 40's

broke_n_bummin

If they're wood props. When you use nylon, it's not so much a matter of thrust, but the weight of the prop on the engine. The 10X6 should work fine ... Look at the GeeBee ... it flies just fine, and the prop just barely clears the cowl.