Tractor Vs. Pusher
 

Someone suggested that I purshase APC props because they have more bite. So, I went on tower to look at them. It says that these props are tractors, not pushers. What exactly does this mean? Obviously tractors pull something, which in this case would be a plane. Are these props simply not made for planes with the engines mounted in the back?

RE: Tractor Vs. Pusher
 

Yes. You need different props for pusher planes.

RE: Tractor Vs. Pusher
 

> Are these props simply not made for planes with the engines mounted in the back? <

The issue is not whether the engine is mounted in the front, in the middle or at the back. It depends on the direction that the motor shaft rotates. Few piston engines can be made to reverse their direction of operation but electric motors do so easily.

RE: Tractor Vs. Pusher
 

Tractors pull, pushers push.

When an engine is on a model in the usual fashion, pointing forward, the prop rotates counter clockwise. And the tractor props we know and love, and are often the only props you can find in mose LHSs, create pull. If you look at the airplane from in front, where the prop is going to pull the airplane, you see that the prop is going to rotate counter clockwise.

Now point that engine aft and stick it somewhere on that airplane to work as a pusher. But stand in front of the airplane where the prop is going to now push the airplane. And which way will you see that engine turn, and that prop spin? Clockwise.

So it's obvious that you've got to do something to the now aft facing engine/prop. Because if you run it without change, that engine/prop are going to pull the airplane the wrong way.

So what if you just turn that prop over on that aft facing engine and bolt it down "backwards"? Nothing much, because the prop blade still bites the wrong way. Now however, it'll bite poorly because the airfoil is backwards.

So you need a prop that's made to work right with engines that are pointing the wrong way, so that you don't have to do anything to those engines and can use them simply by putting a pusher prop on them.

RE: Tractor Vs. Pusher
 

APC does make "pusher" (or, opposite rotation) props, look for "P" after the size. They don't make them in all sizes though.

And tower does NOT carry the full APC line. I can actually get props from APC at my LHS that Tower doesn't list.

RE: Tractor Vs. Pusher
 

BTW, truth is, there really isn't any manufacturer whose props "have more bite" then all the other mfg's props. No mfg has any real advantage throughout it's line. There ain't no magic brand of props.

Nowadays, there are a number that will cut you a lot easier than another brand, but that's more the result of the manufacturing process. But a brand that can guarantee better "bite" from every prop...... Naaahhhhhhhhh It don't happen that way.

RE: Tractor Vs. Pusher
 

While that's true, it's also true that it's worth trying different brand props in the same sizes to see what works best with your engine/airframe combination.

In may parts of the US, APC and MAS are the two most common props. And in most of the common sizes for sport planes, the APC props tend to have a bit more pitch than MAS props. For example, a MAS 10x7 will sometimes perform simular to an APC 10x6.

Also, in many sizes, the APC prop design is a bit more efficient and the blades are stiffer, which sometimes you can notice in the air, and sometimes you can't. Depends on your exact situation.

RE: Tractor Vs. Pusher
 

What plane?

RE: Tractor Vs. Pusher
 

You can't just flip a tractor prop and try to make a pusher out of it.

The leading edge will become the trailing edge...make sence ?

For nitro..it's not going work.
For electric...yes, just reverse the motor's poles.

A prop is a wing bascailly.
Obviousely different wings have different air foil design for different types of applications.
So you can't just say this is better than that...becuase there's diffrerent series of props,
and airframe designs

RE: Tractor Vs. Pusher
 

- AND - Turn the prop around.