I am planning on building a PT-60 to sort of go back to basics. I am doing this since I pushed to progress quickly to 3D and some high speed planes which I am sure caused me to be somewhat lacking in some finer points. My question is would there be any good reason to put seperate flaps on this plane other than "because I can"? My thought to do this is based on the potential for future planes to have flaps, and this would be a great opportunity to learn how to use them. Any thoughts?

I am also undecided on the engine. I am leaning towards a Saito 72 or a 60ish 2 stroke. I normally overpower my planes but have read repeatedly that a trainer should not be overpowered. Any thoughts?

Thanks in advance for any input.

I wouldn't hesitate to go with the Saito 72. In fact, for a 60 size plane, I'd go as high as a Saito 100 (although that might be a waste of a good Saito 100 - but a 90ish 4-stroke would be fine)

As far as flaps go, while the PT 60 certainly doesn't NEED them, I've yet to find a plane that isn't more enjoyable with flaps, so I say go 4 it!

It's easy to do too, just use the aileron torque rods to control the flaps, and either run a flex rod out to the ailerons from a single servo mounted in the center of the wing, or mount a servo in each wing.

If you want to do FLAPS, there are two ways to do them. One, which would be the easiest, would be to use one servo in each wig half. The second is quite a bit more involved, but pretty neat to see. You make a carriage to mount the aileron servo in, then you hook the torque rods to this servo just as you would for a single servo aileron application. Next, you mount this servo carriage on rails and use a second servo to slide it forward and back. When the ailerons are nuetral, you have flaps when you slide the carriage back and you have spoilers when you slide it forward. In effect, you have FLAPERONS....

Of course, this wing is such an easy build, you could easily add flaps individually.

Thanks guys. I was actually thinking of 3 or 4 servos. I think this plane standard uses 1 aileron servo. But I am assuming the control rods would be inside the fuse with the wings on (based on what I remember of my PT40).

I was thinking if splitting the ailerons and using a servo for each aileron and each flap. If I can put the flaps on the outer portion of the wing, then I could have 1 aileron servo inside the wings and 2 flap servos, if not one per aileron and 1 per flap.

But I also thought that flaps go closer to the fuse, so I am most likely looking at the 4 servo setup.

Is my thinking correct here?

Also, would the ailerons, once split in about half to make the flaps, have enough area to be effective?

Nix the outer flap idea. You get the most leverage out at the tips. You would loose too much aileron authority with the flaps out there. You could use the inner 1/3 of the aileron as your flap. 4 servo's would work great. You could use a computer radio and mix the flaps back in and still have full aileron operation untill you activate the flaps. And finally you want the flaps inboard because they really do not care where they are in the airstream. I am not sure but it would also help in lowering the stall point inboard.

I agree with a nice Saito 90 in the nose. You could use it later on in one of your models. I would hesitate on the 100. But it probably would be the best choice for the future. You would possibly run out of prop clearance with it though. Good luck with it.

Mark Shuman

phread59 - I was thinking half of the original aileron for a flap, but you said 1/3. Will that be enough? I am not questioning your recommendation, just trying to best understand. Also, since I am decreasing the width of the ailerons, should I increase the depth to compensate?

Minnflier has made this suggestion many times. I know it will work. Just give the ailerons a little more throw. I have thought some too. You want to do some 3-D eventually. I think your idea of adding some depth to the ailerons may be good for you. most people would not notice it. You may. I won't really hurt. If you find it too much you can always dial back the throws. I would also suggest you take all or almost all of the dihedral from the wing. It will help some there too. Good luck with your project. BTW you will be surprized how much authority those 1/3 length flaps will have. Half would be serious overkill. And cut back the aileron performance too much.

Mark Shuman

Dean, you don't need 4 servos. 3 is plenty, and you can even do it with two.

But first things first. Phread is correct, 1/3 of the aileron is plenty. You could even get by with a little less than 1/3 (Like about 8" on each side).

The PT-60 is designed to use torque rods in the center of the wing to control the ailerons. These will be used to control the flaps - One servo pushing a split pushrod.

For the ailerons, you can either use one servo in each wing, or one servo in the center of the wing pushing flexible pushrods out to the ailerons.

MinnFlyer - great idea, I did not even think of that. I will probably use 3. Thanks a lot.

Told ya he was right.

Mark Shuman