I’m at least 2 years out from making a purchase, but it is certainly on the list!
I need to do more research on maintenance/parts commonality with the standard rotax engines, as that’s one of my primary concerns.
I’m specifically interested in the EP912i - they claim a 20lb weight reduction over the 912is, which is my most likely engine choice.
The EP916ECi is also interesting with 130hp & less weight than a ULS.
I’m all about conquering the enemy, weight. But when we were discussing HW W&B on the forum a year ago I thought the UL was on the light side if you wanted to carry any baggage.
That’s the problem we have in our Just Aircraft Highlander with 912iS. We can carry a 400lbs passenger since the the pilot sits very close to the CG. But adding ANY weight to the aft storage area, which is quite large, causes us to very carefully calculate W&B on the flight. The front baggage area is much better. Another benefit of the Highlander is that the Fuel tanks, in the wings, is aligned with the CG so there’s not much change as the fuel drains. I’m very keen on getting the W&B data and station points on the current Phoenix and the next prototype. Hoping Sonex Aviation shares…
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They posted the W&B data on the first proto last year. Maybe not current but a good starting point:
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Interesting to note that with 2 people and full baggage weight at 87 lbs you can only have 60 lbs of fuel. A Rotax 912 based engine is slightly lighter than the UL Power engine although you could perhaps make that up with the likely heavier prop required for that engine
Thanks, somehow missed that! I’m guessing the two Aux Wing tanks will be about the same Arm as the pilot/passenger based on the pictures I’ve seen.
An Edge Performance modified Jabiru 3300 gen 4 will also be an option soon.
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My engine choice was made entirely be chance. A gentleman reached out to me about a Jabiru 3300 GEN 4 for sale at a local airport and connections were made to view it. It was mounted on a Zenith and the builder of that aircraft had changed his mind about power plants and was wanting to unload the new never fired Jabiru. It came with the muffler, air ducts, and other accessories and he was wanting to make a quick sale for $15,000, a $12,000 discount off current pricing and no shipping fees!
Crazy deals are out there, I am extremely happy this one came my way.
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I’m building the highwing and debating between Rotax 915 and UL, any thoughts to help me decide
I was leaning towards the UL before this deal fell into my lap. I have owned a couple Rotax 912UL carbureted versions in the past on Kitfoxes and hated them, I understand the IS models are much better. I just couldn’t consider the 915 which is approaching $50k or more totally due to it’s price. I got a quote for a FF UL 350 of $37k which is more reasonable.
My own process is to consider reliability first followed by weight, price, then HP.
I remember seeing somewhere that Sonex said that the a Rotax would weight slightly more than a UL Power engine due to the cooling system. I’d find that believable but I don’t think it would be enough that I’d make a decision off of it. I’d also be curious where the CG of the install is between the steel gears in the gearbox on the Rotax vs the different size and structure of the heads and the position of the coolant radiator. The fuel injected 912is version is also a bit heavier than the ULS. Someday I’ll try to add up the weight of my installation.
If/when I were to build a Highwing I’d love to see the 912is performance numbers (or calculated ones) to see if that would satisfy me since for the price it offers really good redundancy, reliability and efficiency. For more performance it would be a more complicated decision since the Rotax is a good chunk more expensive but might have some awesome cruise speeds at altitude with a turbo.
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I would be intersted to hear your reasons for hating them. 
Chattering gear box issues, the 5 year hose replacement, carb balance problems, breaking exhaust and muffler joints, and screaming along at 5K rpm just to get close to 100hp are a few of the reasons.
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They’re obviously different aircraft, but the RV-9 with a 916 has some pretty crazy performance numbers, especially at high altitude:
Wow … nice to find that option happen. May not matter however the original purchase date is when any factory warranty started. That probably would not matter to me. Just something that a person might want to consider… fwiw. I went to Shelbyville this spring to a Jabiru class. Liked what I saw and learned.
$12k off would cover a good bit of warranty work!
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I talked with Casey at OSH and he said the 916 would require a constant speed prop so going with the 915 would save you about 10 grand on a build.
Well …
I guess it was bound to happen,
Just a matter of time!
The egg man is seeking to enter the contest.
None for me … no thanks …
Dale
3.0 Corvair/Taildragger