ul power 350is

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ul power 350is

Postby jasonbourne007 » Sun Feb 01, 2015 12:34 pm

I was curious why this engine isn't used more in the Highlander...
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Re: ul power 350is

Postby RV6 » Sun Feb 01, 2015 6:01 pm

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Re: ul power 350is

Postby BucF16 » Sun Feb 01, 2015 8:14 pm

Wow I hate to make this my first post, but this is thread is on the front page:


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Re: ul power 350is

Postby Swoopjack » Mon Feb 02, 2015 12:27 am

Buc,the post you're referring to is for the 180 horsepower. The 350 is is 130 horsepower. It is still kind of heavy though 170 something pounds. Swoop out
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Re: ul power 350is

Postby av8rps » Mon Feb 02, 2015 7:21 pm

jasonbourne007 wrote:I was curious why this engine isn't used more in the Highlander...


Don't feel bad for asking about the 180 hp UL engine (assuming that is the engine you meant) as I too am really curious about how that engine works out in a Highlander. Even if it gains 100 lbs of empty weight, if it really produces a true 180 hp and one can convert that to an equivalent thrust of what a Lycoming 180 will do, that Highlander should be a rocketship.

I'm certain the Highlander airframe can handle it, as some of the SuperStols are over 800 empty, and they perform just great with 100 to 130 hp.

Plus, a 180 hp Carbon Cub weighs in the low 900 lb empty weight range, and look how they perform.

I think the only reason that the 180 hp wasn' t done before is because the 912 / 914 series Rotax works so well. But these are experimentals after all. So it's ok to try different things...

And if you were asking about the 130 hp UL, it has been done on a Highlander before. And from what I remember, once the original teething problems were sorted out, the 350 worked well. If you search this forum for UL350IS I think you will find pages and pages of discussion on that engine.

Oh, and Buc, keep posting. We'd love to hear more from the silent majority. The more the merrier. :D
Last edited by av8rps on Mon Feb 02, 2015 7:42 pm, edited 1 time in total.
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Re: ul power 350is

Postby kenryan » Mon Feb 02, 2015 7:36 pm

One possible reason that the UL350iS is not used on more Highlanders and SuperSTOLs may be that STOL airplanes prefer longer props, and the installation manual for the UL350iS states:

"Choose a propeller with a maximum diameter up to 1650 mm." That's 65 inches.

UL will tell you that you can use whatever size prop you want. Okay, if that's the case, why haven't they corrected their Installation Manual in over 4 years? If you were trying to sell engines, would you want your installation manual to incorrectly show a drastic limit on prop length if there was really no such limitation? To me, something is fishy.
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Re: ul power 350is

Postby danerazz » Mon Feb 02, 2015 8:03 pm

If you think that is heavy, I am putting a 230lb rotec radial on mine...

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Re: ul power 350is

Postby av8rps » Mon Feb 02, 2015 10:27 pm

It would be interesting to know if Steve were to build another Highlander if he would use another UL 350? From all I could tell, it looked like his airplane performed very well. I can't remember for sure, but I thought he was running a 68 inch prop. Overall I agree that a longer prop is better. But I think if you can get into the 68 inch prop size, you can still make a lot of thrust. Case in point is the good climb rate Jack L is getting with his 68 inch 3 blade sensenich. And a really good cruise too (Check out his comments in the flying skis thread where he discloses his performance numbers).

A Rotec radial on a Highlander....COOL!!

Kitfox played around with one of those on their Model 7 Super Sport Kitfox. And they discovered that it performed just slightly under what a Rotax 912s will do, probably due to tbe extra weight. But...it sure had a cool factor that was off the charts. And sound to match! So I would think even at 230 lbs engine weight, you're going to have a good performing Highlander. But plan to spend a lot of time at airports... John McBean at Kitfox told me everywhere he went with his radial Fox he attracted admirers of the plane that had a million questions. I would love to have a Rotec on a floatplane as I just think that radial cries out for float flying. But I have my Rotaxes already, otherwise I'd strongly consider the radial.

Oh, also if you ever get too old to fly you can just remove that Rotec engine and hang it on the wall just to look at. 8) It is one beautiful engine!
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Re: ul power 350is

Postby Augustus » Tue Feb 03, 2015 5:53 pm

Ever heard the saying, "everything in moderation?" The most reliable engines use water to "moderate" the temperature extremes inside the cylinders. Water works seems to work better than air from my experience. I've seen the "R word" engine go for over 2,000 hours without mechanical intervention.
So I went kicking and screaming with a (gulp) Rotax. In the name of the Father and the Son and the Holy Spirit, Amen.
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