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Which engine .75 or .91FS in Snr Telemaster & SSporster 60 + intro

Hey all...

My latest building projects are a Senior Telemaster (general purpose utility plane, cameras, trainer, etc..) and a Great Planes Super Sportster 60 (low wing trainer, sport flier).

I have in hand two engines for these planes. An OS .91 FS Surpass circa

1991 or so, and a brand new Tower Hobbies .75.

Any thoughts on which engine to put in which plane?

---------------------------- For my own introduction, I flew for a few years back in the early 90's or so. I flew a 99" Olympic II sailplane with a .09 powerpod, a GP PT-20, a GP Trainer 60 (built with less dihedral, OS .61 long stroke. Loved that plane), a Goldberg Super Chipmunk, and the most challenging, a Sig Smith MiniPlane Biplane. I took a break for a bunch of years, and have just started back into it. The Olympic II still flies great, and slow, and takes FOREVER to deadstick (heh heh). I tried the old PT-20, and it wouldn't roll on the grass field, so I put a couple of flights on it hand launched... The flights were good, but the launch is no darned fun! No crashes... No scary bits, apart from hand launching the PT-20 :) So I can still fly, at least a bit... The Trainer 60 I sold years ago (pity), the chipmunk didn't survive a move (but I have the .91FS from it), and there's no way I'm trying the biplane at the moment!

Regards, Ron

Reply to
Ron
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.91 in the Telemaster .75 in the Sportster

Reply to
Don Hatten

I agree. The Sportster really doesn't need the additional weight of the four stroke. The Telemaster can handle it without you noticing it. However, the Telemaster will be way overpowered. I flew mine with a Saito 65 and it was plenty strong.

Reply to
Robbie and Laura Reynolds

I appreciate the responses, thanks!

I don't understand the reasoning, however.

The .91FS w/muffler weighs 23.8 ounces. The .75 w/muffler weighs 23.6 ounces.

Is 2 tenths of an ounce really going to make that much difference? That's less than 1% difference in weight.

Or is there yet some other reason, yet unstated? How about slowing down for landings? Is that a consideration?

Thanks, R> >

Reply to
Ron

The four stroke has more torque so it's ideal for big draggy airframes like the Telemaster.

The two stroke likes to rev higher so it's ideal for your Sportster. Less drag, lots of RPMs = perfect

Don

Reply to
Don Hatten

Ah, another young-un that needs teaching!

Reply to
Paul McIntosh

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