Rotax 915?

[Clark in AZ]

So, other than John McBean at Kitfox, is anyone running a Rotax 915 yet? Love to hear your thoughts on the install and of course the performance.


Clark

[Esser]

I don’t think the engine is officially released yet or it’s JUST been released. No flying examples besides the factories. Trent is getting one but I think the factory is doing his install.

[jimx1169]

Trent Palmer has his flying now. Lots of his vids on youtoob

https://www.youtube.com/watch?v=mefCAXRjCfA

[Yamma-Fox]

Sounds like 915 installs go north of $60k when you count all the extra pieces and canbus integration.

That and the weight comes in pretty high so I wonder if this motor might find a limited market.

[Rik]

That’s making an IO-550 look cheap.

[Esser]

Til you put fuel in a 550

[Clark in AZ]

Sounds like 915 installs go north of $60k when you count all the extra pieces and canbus integration...



Love to hear John McBean's take on this?


Clark

[Rik]

Til you put fuel in a 550

True, until one looks at how many hours a 550 can reach and how fast the planes are. 60k for 140 hp is expensive no matter who you are.

[Yamma-Fox]

Love to hear John McBean's take on this?


Clark

Yes I would too. My 60k number comes merely from forum (other) surfing/research. So take that fwiw ;)

Hopefully I am mistaken and it would come out cheaper and lighter than others who have done it report it to be.

[Flyboy66]

I think it is like freeze dried food on a camping trip. It is expensive but gets the job done. For the short field back country flyer, it is relatively light weight, and makes takeoff power to much higher altitudes than most people fly.

Does everyone need it? No, most people probably don’t. Would most people appreciate Santa hanging one on their Kitfox, probably yes.

For what it’s worth, my garage is pretty cluttered up, so I would have no objections if Santa just left it on the carpet by the fireplace. But if he doesn’t leave one, my number will be less than 915.

What prop is the 915 designed to use? How much is it?

[aviator79]

That’s making an IO-550 look cheap.

That $60K is for the whole installation, including a prop and instrumentation. The engine on its own is $30k cheaper than the list price of a new IO-550. ($10k less than street price) Also, nobody in their right mind would try to install an IO-550 on a Kitfox.

[Rik]

Obviously your missing the point here. I was making a comparison between what the cost of a Rotax is vs a more established, more powerful and more accepted engine.

I never implied someone would stuff an IO-550 into a kitfox. It was what we refer to as an analogy to draw a comparison towards value.

[aviator79]

I didn't miss your point, and wasn't trying to get personal. Just pointing out the flaw in the comparison. $60K is for a complete factory new firewall forward on the 915.

[rv9ralph]

I was making a comparison between what the cost of a Rotax is vs a more established, more powerful and more accepted engine.

Rotax is an established engine option. Also, the Rotax engine was engineered in the early 80's using modern metallurgy compared to Lycoming/Continentals. It has a proven history, good to excellent power output at a lower weight. Which results in an added benefit of not carrying extra weight which reduces performance. Fuel efficiency means not having to carry extra fuel which is extra weight.

Ralph

[Esser]

My 914 was originally on a Predator drone. Battle proven ;)

[efwd]

Well it looks like your Rotax was reinstalled into another Predator. I love that Plane.

[Slyfox]

is this the only engine that can go into the Sti? if not, what options for an engine are there?

[Esser]

You can put anything in the STi. Trent used to have a 912UL in his. He did bump up the power to 105 at some point.

The STI was designed for 100mph 100’ landing and take off, on 100hp


Thanks Eddie! I love the way she looks AND performs

[Slyfox]

oh, I see. you can land in 100feet with a 40k kit and 60k engine (including all needed extra's) oh my. hay wait, I landed in 100feet the other day, no problem. what's the big deal. I only have a model 4. and my speed is 118mph

[DesertFox4]

Steve, since the STi version utilizes a 7SS fuselage I’m thinking just about every engine they offer on the standard kit might be able to be used on the STi. What I know is the factory has flown the STi with first a 912uls, then a Titan 180 hp. engine and now the 915. The 912 iS fuel injected and 914 should work well too.
Maybe a Rotec radial. I really haven’t asked them so I may be way off. ;)

[Slyfox]

I was just trying to get the jest of this thread. I'm sure any engine would work. I just don't see the 915 being a viable answer

[Flyboy66]

There are always people who want more. If one has the money and wants the option, it is available. Dodge sells a Tradesman version of the Ram that is basic. The Laramie is 15 grand more and some people think it is worth it to have leather seats, heated steering wheel, and a navigation system (and more). The 915 is expensive, but offers extra performance that fits this airframe.

People add VG’s, big tires, strut fairings, Big Bore kits, turbos, and other stuff to enhance performance in different areas. Some are cheap, some are expensive. This is just an extension of that process. An expensive one. But there are people who will spend the money. Does anyone really need a Garmin G3X? Lots of people buy them.

Trent was happy with what he had until he flew the 915. He decided it was worth the money for what he does. And there are others who intend to install the engine on their planes. I would love to have one, but I don’t need one and can’t justify the expense for the type of flying I will do.

[mooreaa]

The original docs for the 915 said it had to have a CS prop but I’ve seen two installs (including Trents) that are running a fixed pitch.

The ability to use a fixed pitch seems like it could save 8-15k. Might not get the full advantage of the engine.

Re avionics it sounds like you need to have their Fadec as the g3x doesn’t provide the same insight. Any reason for this? And is the fadec included in the 30k price?

Note that one reason for not putting a CS prop on it is that you can’t classify the plane as a LSA/eLSA

[aviator79]

It's a $38,667 engine. That does not include the control unit. You'd be leaving a lot on the table by not putting a constant speed prop on it. It's like buying a Corvette with only one gear. I don't think this hits the mark for a builder who is trying to stick to a budget and keep it LSA. The 912iS serves that market.

[av8rps]

I think everyone is looking at the 915 option wrong...

Let's face it, Trent went out and competed in the STOL drags in his new 915 powered Kitfox AND BEAT EVERYTHING THERE EXCEPT a turbine PT6 powered multi-million dollar "extremely modified for STOL" Wilga (that incidentally is still wowing the aviation world). Oh, and he did that without having the constant speed prop on his plane that really will make that 915 perform, AND he had virtually no experience in his Kitfox with that engine on it!

So 30k, 50k, 60k, or whatever? Even if that engine install was 100k, that is damn impressive. And regardless of the price, it also proves just how capable the Kitfox really is.

I salute Trent and Kitfox Aircraft for working so hard to bring us that great option and to show us just how capable our planes can be. Even more amazing, it is still only about half the price of a Carbon Cub.

It's all a matter of perspective.

And don't think there haven't been a few of us thinking about how a Model 4 might crank up with a 915 on it ;)

[Av8r3400]

Not to argue with your point on the 915, Paul, BUT, Trent did not have the second best time at High Sierra. That honor belongs to Steve Henry who met Mike/Draco in the first round and was eliminated.

Someone put up the times for the entire bracket of races (which I can't find now...) and Steve would have beat any and all of Trents runs handily. Steve's new turbo-Yamaha (near 300 hp) powered plane is being built with the sole purpose of beating Draco...


This is not intended to take away from Trent's accomplishments with the new FreedomFox build and everyone who took part in it.

[av8rps]

Thanks for that info Larry. I didn't know that.

I think you know that I really like both Steve and Trent, but in Trent's defense his Kitfox is pretty much a stock Kitfox STI with a 915is and a few extra bells and whistles / creature comforts making it a bit heavier than it really needs to be. Comparably Steve Henry's Highlander is a pretty wild, far from stock Highlander with Oratex covering, bare bones, everything possible done to lighten it up, and uses modded out extended wings, flaps, etc, and then uses a 160 hp yamaha snowmobile engine that has been modified for aircraft use, not a production aircraft engine like the Rotax is. Oh, and he uses nitrous too!

I was wondering how it was that Trent could beat Steve's Super Nitrous Highlander, and now I know. But honestly, if Trent could even run on the tail of Draco and Steve Henry's Nitrous Highlander with his relatively stock Kitfox 915 STI, it says a lot.

Geez, a 300 hp Highlander? Wow'sa...:eek:

[Esser]

Not to argue with your point on the 915, Paul, BUT, Trent did not have the second best time at High Sierra. That honor belongs to Steve Henry who met Mike/Draco in the first round and was eliminated.

Someone put up the times for the entire bracket of races (which I can't find now...) and Steve would have beat any and all of Trents runs handily. Steve's new turbo-Yamaha (near 300 hp) powered plane is being built with the sole purpose of beating Draco...


This is not intended to take away from Trent's accomplishments with the new FreedomFox build and everyone who took part in it.

Not to poo poo on Steve's accomplishments but the wind played a huge factor as it picked up. Toby raced right after Steve and had a I think a 1:23.24 time vs Steve's 1:22.76 . After the wind picked up the times were almost all a few seconds longer including Draco(1:17 first round vs his winning 1:21) . Toby's 3rd place win was with a time of 1:27.39 vs his 1:23.24. Trent's second place winning time was 1.27:27

Steve's time was impressive and I think his machine would have beat Trent with way more HP and lighter weight. I'm just saying that Trent's time would have been close than people think and EVERYONE who builds a plane has the ability to build a Kitfox that performs like Trent's with no experimentation. The same can't necessarily be said for a Nitrous Apex powered modified Highlander.

[av8rps]

Very good explanation Esser. It makes a lot of good points.

[jmodguy]

Really doesn’t matter because a “stock” Kitfox is never going to beat a machine like Draco. It’s like a drag race with a pro modified vs a Chevy Impala. Only way to make it interesting is to break it up into classes.

[bbs428]

Fwiw -

Agreed Just like the drag races. Stock, super stock and comp.

The problem, as I see it is the complexity of all this on the organizers of the event. It's already becoming a very popular, large venue.
A "friendly" street race has no classes... and if it stays the same or morphs into a more complex race, the emphasis should always
be friendly fun for all involved.

Rumor has it that Draco will have a lot more competition this year... :D

[Esser]

Draco isn’t competing this year. Mark’s new plane will be there. From what I understand he’s trying to make the cheapest STOL machine

[bbs428]

That's good news.

I like that he's building a budget STOL. Should be even more fun!