Will a O.S. .25 FX have enough power for a 25 size trainer?

Sure. The FX series are really good engines.

You have not mentioned the size of the plane you are considering. A great trainer is the Sig LT-25 and a .25LA engine is all that it needs. It would be a waste to put a ball-bearing engine in the plane.

I have a Lt-25 with anOS 32 sx and that combo works just fine,Your 25 sx would also do well and could be moved to your next plane.If you already have it,fly it!

The .25 FX has enough power to fly a Tower Trainer 40... (not very aerobatic... but it will fly just fine.) That engine has more power than some of the cheaper .40 ci engines.

A little more power usually helps. The extra oomph from a 25FX will help when the day is hot with no wind and with grass fields. Or when the wind picks up. Even better with a 32SX![8D]

Others include the Goldberg freedom 20 and Eaglet 50

Great planes PT-20 is a goodie. A SIG Kadet Seniorita as well. The SIG LT-25 is hard to beat. That engine will do al of these with ease (OMG I did the rhymie ting LMAO). Good luck with whichever plane you choose.

Mark Shuman

PS: these are all kits and must be built.

I'm actually thinking of putting my 25FX on my old Superstar 40 trainer. Think it would work. I understand it would not be very acrobatic, but I just want it to be able to fly and do taouch and goes without too much trouble and maybe be able to handle a little wind on landings.

Caution... if you get an instructor that doesn't know how to "fly the wing" instead of "point the engine" the low end of the recommended range engine will give HIM problems.

Someone that understands power management can do fine. Someone who has become dependant on excessively abundant power wold be in trouble.

Its a different style of flying than what you see at most fields.

I agree with FHH on this one, a lot of guys, even (maybe espeically) experienced pilots are sloppy and have gotten used to having way more power than they know what to do with.

But it is certainly possible to pull your typcial .40 size trainer with that engine.

As a suggestion, put a low pitch prop on the engine, something like a 10x3 or 10x4 will help pull the big trainer will the smaller engine.

Actually guys I am an official club trainer at my field. I understand all the issues dealing with underpowered planes. I have decided to try out a .52 4-stroke on my trainer. I think I will be much happier with that setup. I much prefer 4-strokes anyway unless I am looking for speed, then the 2-stroke is my choice.

I am training a guy right now with a Goldberg Eagle II with a OS .40FP. My OS .25FX shouldn't be too far from the power of this motor and I don't like the way it flys. Too underpowered with the 40FP. The plane will fly but is way underpowered IMO. I figured the 25FX can't be too far from this performance so I am looking elsewhere for power.

Thanks,

I would rather have extra power rather than juat enough even on a trainer. When someone makes the effort to make it out and try to get some training, wedon't want to say no just because it might be windy. If its in the afternoon the winds can suddenly double in speed and then the extra inch of prop or higher rpm available really helps to get the plane back down in 1 piece. The extra power can also be used to teach that you can fly with more than just 2 throttle positions!