First the Lidl Vulcan maiden, now the maiden all foamboard version - it was FAST!

[Stephen Jones]

Posted by David P Williams on 24/01/2021 19:09:32:

Posted by Bonzo Moon on 14/01/2021 21:19:23:

Sorry mate but there is actually no such thing as a pusher prop!

Sorry Bonzo - that may be true for you leccy flyers where you can choose which way you want the motor to turn, but for us i/c chaps where the engine only goes one way, pusher props definitely do exist.

And Electric motors too Look at Quad motors they have a locking nut that will come off if they are run in the wrong direction and that is why there are (CW) clockwise and (C.CW) counter clockwise props.

Steve.

[Bonzo Moon]

Posted by SIMON CRAGG on 24/01/2021 17:02:26:

Bonzo....

Did you find the c/g on the plan about right?

I have got a 3s1350 33c which should be ok.

Hi Simon, yup, CoG seems good as specified.

Re the pusher question I seem to have stirred a hornets nest with my comment that 'there's no such thing as a pusher prop'. However I Googled years ago re this subject and it's what I'd seen. It's an old hot topic! Plus it's logical to me?

I have no doubt that a lot of people on here have far greater knowledge on this than I do, AND I agree, some props are sold as 'pusher props'. I think they just mean opposite hand. But please check out some of the quotes I took from other groups.

'Google' ... Does a propeller push or pull?

This action, of course, occurs on all the blades around the full circle of rotation as the engine rotates the propeller. So the propeller is both pushing and being pulled through the water.

I appreciate the point that IC engines only run one way and it's easy to change the direction of brushless motors but putting a left hand prop on doesn't mean the prop is acting in a different way to a right hand prop. It's pulling and pushing.

And obviously you get left and right hand props for drones, it cancels torque, they wouldn't work any other way, but they aren't pusher props, they are just left and right handed,

If you had a model with an IC motor that was aft and in a pushing location, if the prop is fitted with the size info facing forward it is pulling. All props push air? It's called thrust.

Check out the links I posted above and below....

There's really no such thing as a pusher prop. There are CW and CCW props and for IC engines that can't turn in reverse you need the right sort for the mode or location. But for electrics which turn in either direction we can use either type of prop in either tractor or pusher mode.

Steve

And

On quad copters they use two motors turning CW and two running CCW to balance out the torque and allow for yawing by cross controlling the motors. This requires matching props that only differ by being pitched for the different rotations. This is also why you'll find a lot of examples of such CW and CCW pairs. Before this quad copter invasion we did not used to have such a variety of reverse rotation props available.

If you are flying a single motor model with the motor set up as a pusher then you can use either sort of prop. Just set the motor up to rotate the proper way.

Note that any prop used on an airplane model should be set up so the side with more curve to the blade's airfoil faces forward.

THIS IS THE KEY POINT!

AND on this link ... Flight Test Forum

As some have stated, the difference between a so called "pusher" or "puller" AKA "tractor" prop is just the direction of rotation. Since electric motors can spin either way you can put a so called "pusher" prop on the front of the plane, or a so called "puller" prop on the back of the plane. Standard rotation props, AKA Puller, AKA CCW (Counter Clockwise Rotation when viewed from the front) are still a bit more available, though that is changing rapidly, at least for the sizes that are commonly used for multicopters, which need both directions of rotation even though they are almost always set up to "pull".

Which is exactly what I said!

Anyhow, I'll say no more!

Please read the discussion on RC Groups here! Pusher props??? And the other one I linked above.

Enough of this anyway, it'd be nice to be out flying!

And good luck with the maiden Simon, take some video!