Rotax 916

MPB

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Coming to your nearest Cessna 172 or Piper Warrior - a Rotax 916?
 
Here's the press release: https://www.prnewswire.com/news-rel...isc-aircraft-propulsion-system-301783516.html

This is a game changer for any Lycoming 160hp applications

It want be a game changer until kit manufacturers embrace and support it. People don't want to re-invent the wheel when it comes to kits these days. Sonex is very reluctant to support rotax options. Vans keeps trending towards larger engines and the extra weight of the legacy engines is needed in the design. Seems the only people really embracing new Rotax engines for their experimental are Kitfox and Rans. If Vans did step up and offer a Rotax 916 rv7/8 then we could call it a game changer.
 
It want be a game changer until kit manufacturers embrace and support it. People don't want to re-invent the wheel when it comes to kits these days. Sonex is very reluctant to support rotax options. Vans keeps trending towards larger engines and the extra weight of the legacy engines is needed in the design. Seems the only people really embracing new Rotax engines for their experimental are Kitfox and Rans. If Vans did step up and offer a Rotax 916 rv7/8 then we could call it a game changer.
160 horsepower would be pretty weak for a -7 or -8, as 180 is the basic design and a fair number have 200. Now if they come out with a 180 horsepower engine, I’ll be one of the first in line to swap it in.
 
It want be a game changer until kit manufacturers embrace and support it. People don't want to re-invent the wheel when it comes to kits these days. Sonex is very reluctant to support rotax options. Vans keeps trending towards larger engines and the extra weight of the legacy engines is needed in the design. Seems the only people really embracing new Rotax engines for their experimental are Kitfox and Rans. If Vans did step up and offer a Rotax 916 rv7/8 then we could call it a game changer.
160 horsepower would be pretty weak for a -7 or -8, as 180 is the basic design and a fair number have 200. Now if they come out woth
 
Coming to your nearest Cessna 172 or Piper Warrior - a Rotax 916?
Or… sling high wing. I found out about this last year at Oshkosh from one of my friends that had his plane on display. It’s a really nice engine
 
160 horsepower would be pretty weak for a -7 or -8, as 180 is the basic design and a fair number have 200. Now if they come out with a 180 horsepower engine, I’ll be one of the first in line to swap it in.
It's almost 100 lbs lighter than a 180 hp and turbocharged so it will keep it's 160 hp nearly all the time. In the real world I bet they would perform nearly the same.
 
I’ve been watching the rumors of Rotax 916 because I want to build a Sling High-Wing.

The kit is designed for 915is, which gives great turbocharged cruise performance but (IMO) I’d want a few more HP to help on takeoff. The 916is should be a close-to-drop-in replacement for the 915IS ??? (Early rumors were that this is the same engine as 915 just with more boost)

Edit:
On sling pilots forums, they said it should be straightforward swap, but for TSI builders they will be shipping new FWF (Firewall forward) kits for 916 and conversion kits for those who has 915 FWF and want to install 916. So for High Wing it should be straightforward.
 
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It's almost 100 lbs lighter than a 180 hp and turbocharged so it will keep it's 160 hp nearly all the time. In the real world I bet they would perform nearly the same.
My understanding is that 160HP (Max rpm) is only for 1 minute..... maybe I'm misreading it.
 
My understanding is that 160HP (Max rpm) is only for 1 minute..... maybe I'm misreading it.

what I’m hearing from the Sling TSi discussions is time-limited on the higher HP for 3 minutes:
https://slingpilots.com/forum/viewtopic.php?f=23&t=345

so, I interpret this as 915is engine but with a time-limited extra boost pressure to help the takeoff.



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Coming to your nearest Cessna 172 or Piper Warrior - a Rotax 916?
Not unless you can get an STC for that swap.
 
Here's the press release: https://www.prnewswire.com/news-rel...isc-aircraft-propulsion-system-301783516.html

This is a game changer for any Lycoming 160hp applications

I flew Rotax powered planes (among other things) for 7 of the last 12 years.
I have nothing bad to say about the engines.
People grumble about "burping" the engine before starting it, but I've never climbed in any GA aircraft without pulling the engine through 5 or 6 times, so it was never a "chore" to do it.

what I’m hearing from the Sling TSi discussions is time-limited on the higher HP for 3 minutes:
https://slingpilots.com/forum/viewtopic.php?f=23&t=345

so, I interpret this as 915is engine but with a time-limited extra boost pressure to help the takeoff.

This is a Light Sport limitation. At full power, the plane will fly too fast for the bogus FAA artificially constrained top speed.
It probably doesn't apply if you put it in something that's not classified as Light Sport.
 
There is zero chance that I'd be interested in trading my current O-320 for a turbocharged, liquid cooled, geared engine that makes the same power with a non-field serviceable pressed-up roller bearing crankshaft and engine control software that ties me indefinitely to the manufacturer.

Also, every time I hear a Germanic company rep describe the product as 'perfect' I know it's time to run.
 
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This is a Light Sport limitation. At full power, the plane will fly too fast for the bogus FAA artificially constrained top speed.
It probably doesn't apply if you put it in something that's not classified as Light Sport.

negative… the Sling TSi (which uses 915is/916is and the referenced thread, and based on the Sling 4) is a 4 seater and definitely _not_ flying under Light Sport limitations. You are confused with the Sling LSA / Sling 2 aircraft, which uses the 912 engine.


Even with the stock 915is engine , the Sling TSi’s had a run-time limitation on how long you can run at max takeoff power with their FADEC/electric prop control… on 915is its 5 minutes max limitation at Fine Pitch settings, after that you needed to dial the prop control back (lower RPM’s ?).

I don’t own a Sling, but read a lot since I want to build one… it appears to be related to engine cooling or other stress factors. Doesn’t appear to be just sling, I see other airframes using these engines have similar takeoff power time limitations, appears to be a limitation from the Engine manufacturer itself??
 
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Not unless you can get an STC for that swap.
FYI: An enterprising individual can put one of the mentioned aircraft under experimental exhibition and drop a 916 in vs the STC route. If they're talented enough to keep it a modular install, can even convert back after the fun wears off.
 
There is zero chance that I'd be interested in trading my current O-320 for a turbocharged, liquid cooled, geared engine that makes the same power with a non-field serviceable pressed-up roller bearing crankshaft and engine control software that ties me indefinitely to the manufacturer.

Also, every time I hear a Germanic company rep describe the product as 'perfect' I know it's time to run.
Yeah, it would be awful to be able to run mogas, have consistent engine temps, and FADEC controls which make it a breeze to start in any conditions. I'd rather be working primer pumps and mixture controls while burning greater quantities of more expensive 100LL with plug fouling tendencies and increased frequency of oil changes.
 
There is zero chance that I'd be interested in trading my current O-320 for a turbocharged, liquid cooled, geared engine that makes the same power with a non-field serviceable pressed-up roller bearing crankshaft and engine control software that ties me indefinitely to the manufacturer.

Also, every time I hear a Germanic company rep describe the product as 'perfect' I know it's time to run.
That was my opinion many years ago too when the 912 first came on scene. Since then I've seen enough of them to know it's a superior engine to the legacy 100-150 hp engines. It's very rare to see a modern rotax have issues or show any wear at tbo. If aerobatics are a desire they obviously will not work for that. Given the choice of a new Rotax or a <160 hp lycoming/continental for straight and level flying I'm choosing the Rotax every time.
 
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Yeah, it would be awful to be able to run mogas, have consistent engine temps, and FADEC controls which make it a breeze to start in any conditions. I'd rather be working primer pumps and mixture controls while burning greater quantities of more expensive 100LL with plug fouling tendencies and increased frequency of oil changes.

What isn’t doing an inappropriate hand motion on the primer while making eh, faces, part of the rite of passage for pilots?
 
The maximum power time limits are not very limiting if you have an engine that can come off the runway to a1000 FPM climb.. The is dialing back at pattern altitude, which at most airports is a safe altitude for initial flight. The cruise climb from there is where we can usually be patient. One limit is easy to remember.

Shades of the old round engines, with MTO, METO, MC values which changed with temperature of the air, and even oil temperature at take off time. Real pilots back in the day had a complicated power management problem, and they usually had a flight engineer to control those limits.

For those who are not familiar:
Max Take Off
Max Except Take Off
Max Continuous
 
That was my opinion many years ago too when the 912 first came on scene. Since then I've seen enough of them to know it's a superior engine to the legacy 100-150 hp engines. It's very rare to see a modern rotax have issues or show any wear at tbo. If aerobatics are a desire they obviously will not work for that. Given the choice of a new Rotax or a <160 hp lycoming/continental for straight and level flying I'm choosing the Rotax every time.

I love the word “superior” in this context, it fits right in with Rotax saying it is “perfectly developed”…. all reads like typical Euro nonsense to me, as a European myself. The manufacturer will doubtless continue telling you that as you’re paying to fix whatever development issue has reared its head on that particular week after 35 years of Rotax development.

I’ve flown 912s and dealt with their BMW motorcycle carbs and their Ducati voltage regulators. I’ve also dealt with them in highly improved turbocharged form in my job. The newer factory injected ones are having renewed gearbox issues right now for some reason, as well as wiring issues for the EFI.

I bought a plane with an O-320 for a reason, and it wasn’t ignorance. If the thing only makes 150 HP I for sure don’t want to maintain a turbo or radiator/hoses. I’ve pressed together and trued-up needle roller bearing crankshafts with my own hands and don’t want a plane with one of those either when overhaul time comes. I’ve tuned electronic fuel injection myself, using software developed by a small group of individuals including me when the OEM wasn’t around or cooperative. My plane is mildly aerobatic, that’s actually not something I’d thought of but it’s a good point too.

When I’m spending my own money on something I maintain myself and plan to continue maintaining myself indefinitely I prefer a stone-axe simple engine that is just as efficient, has a hundred places supplying parts and machine work when overhaul time comes and which can be overhauled without throwing away major assemblies, e.g. crankshaft, turbo and the like. You can of course spend your money however you like.

My entire plane cost 70% as much as a 916 Rotax engine BTW, complete with 900 TT O-320 that is still running well 13 years later.
 
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A good engine - sure. Something revolutionary? No. Cost is $50,000 (higher than legacy alternatives), TBO 2000 hours (same as legacy), has max power time limitations, needs a turbo to get to 160 hp, etc.

Give me more HP, less weight, 50% more TBO, no turbo, no time limitations on power. And sell it for less. Asking for a lot? Yes - game changers need to bring a lot. Just somewhat better won't really do it.
 
The maximum power time limits are not very limiting if you have an engine that can come off the runway to a1000 FPM climb.. The is dialing back at pattern altitude, which at most airports is a safe altitude for initial flight. The cruise climb from there is where we can usually be patient. One limit is easy to remember.

Shades of the old round engines, with MTO, METO, MC values which changed with temperature of the air, and even oil temperature at take off time. Real pilots back in the day had a complicated power management problem, and they usually had a flight engineer to control those limits.

For those who are not familiar:
Max Take Off
Max Except Take Off
Max Continuous

can someone expand on the duty cycle? 5 mins per hour? 5 mins per flight? 5 mins max then 30 mins 92% or less?

also, the guy talking about his 320 must not realize that the Rotax will still be pushing close to max HP at 8000 feet when the 160 HP 320 is starting to feel the altitude. I’d guess the Rotax straight out wins above 10k.
 
I don’t fly over 10K feet and couldn’t care less about it myself. I’d guess the market for certified 150 HP engines feels the same way, given that certified planes at that power level are generally trainers like the C172 and Warrior. That is especially the case for 150 HP certified aircraft that are earning their keep in a way that might justify a buying very expensive engine. High altitude with 150 HP (or whatever is correct) might make sense for a privately owned lightweight Sling four seater, but that’s not a huge market.

So what about the experimental sport plane market? Would an experimental RV designed around a 150 HP Rotax be successful? Maybe, but not revolutionary because (1) people like sea level power for initial rate of climb and they like aerobatics, and (2) most of the engines people use in RVs are bought or built up for far less than $50K or whatever and those planes aren’t typically used at 10K feet either for most of their service life. KISS is the RV credo and I don’t see this as that.

I think this is just another attempt to build what looks good on paper to some, but doesn’t actually address the requirements of most buyers. Much like the Thielert, which sells to niches like the US military and GA buyers in locations where aviation gas is $12 a gallon and almost unavailable… and nobody else. The Rotax is different in that it’s based on a successful UL engine, and might sell to the small $200K+ advanced ultralight market in Europe, although those planes don’t go up in altitude much either due to airspace constraints. Otherwise to me it looks a bit desperate, trying to extract competitive power via complexity from a legacy UL product that’s just too undersized for the job.

I’d guess Rotax in actuality expects to sell some of these and to expand their product range a bit but has no expectation of it being revolutionary.
 
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A good engine - sure. Something revolutionary? No. Cost is $50,000 (higher than legacy alternatives), TBO 2000 hours (same as legacy), has max power time limitations, needs a turbo to get to 160 hp, etc.

Give me more HP, less weight, 50% more TBO, no turbo, no time limitations on power. And sell it for less. Asking for a lot? Yes - game changers need to bring a lot. Just somewhat better won't really do it.

To be fair, you should compare a new engine to a new engine for pricing. A new O-320 is around $65k, last I checked. The O-320 is also considerably heavier.

As much as I am a fan of the simplicity of Lycomings and Continentals, I'd consider putting one of these in my Cub if it were a viable option for the weight savings alone. It would make an already light and good performing machine a really light and even better performing one. I could use a bit of a CG shift too.
 
I hear your POV. But the competition / the choice set for an engine buyer with an existing certified plane is going to be a reman or overhauled engine vs the new Rotax. Or for the experimental crowd the Titan, etc.
 
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I don’t fly over 10K feet and couldn’t care less about it myself. I’d guess the market for certified 150 HP engines feels the same way, given that certified planes at that power level are generally trainers like the C172 and Warrior. That is especially the case for 150 HP certified aircraft that are earning their keep in a way that might justify a buying very expensive engine. High altitude with 150 HP (or whatever is correct) might make sense for a privately owned lightweight Sling four seater, but that’s not a huge market.

So what about the experimental sport plane market? Would an experimental RV designed around a 150 HP Rotax be successful? Maybe, but not revolutionary because (1) people like sea level power for initial rate of climb and they like aerobatics, and (2) most of the engines people use in RVs are bought or built up for far less than $50K or whatever and those planes aren’t typically used at 10K feet either for most of their service life. KISS is the RV credo and I don’t see this as that.

I think this is just another attempt to build what looks good on paper to some, but doesn’t actually address the requirements of most buyers. Much like the Thielert, which sells to niches like the US military and GA buyers in locations where aviation gas is $12 a gallon and almost unavailable… and nobody else. The Rotax is different in that it’s based on a successful UL engine, and might sell to the small $200K+ advanced ultralight market in Europe, although those planes don’t go up in altitude much either due to airspace constraints. Otherwise to me it looks a bit desperate, trying to extract competitive power via complexity from a legacy UL product that’s just too undersized for the job.

I’d guess Rotax in actuality expects to sell some of these and to expand their product range a bit but has no expectation of it being revolutionary.

Revolutionary? Ok. I see that I guess. But certainly uncommon and forward thinking. GA needs new ideas, better fuel efficiency, lighter engines, more automation of legacy busywork like mixture and prop. At least this is a move into FADEC and do’s well in the LSA and derivative airframes. 200 knot birds like JMB make the argument understandable from the POV of a future plane owner. I see the appeal of old tried and true but I want something new and shiny. ;)
 
Game changer? No, but glad there are more options now. I also want a Sling high wing and was hoping Rotax would follow through on the rumors from a few years ago of a higher power engine. Would have liked to have seen 180hp as well, but it's still a nice step up.
 
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To be fair, you should compare a new engine to a new engine for pricing. A new O-320 is around $65k, last I checked. The O-320 is also considerably heavier.

As much as I am a fan of the simplicity of Lycomings and Continentals, I'd consider putting one of these in my Cub if it were a viable option for the weight savings alone. It would make an already light and good performing machine a really light and even better performing one. I could use a bit of a CG shift too.
Vans just released SnF lycoming pricing. It's $36,500 for the YO-320 with standard mags which is more of a competitor to the 916 than the O-320.
 
Vans just released SnF lycoming pricing. It's $36,500 for the YO-320 with standard mags which is more of a competitor to the 916 than the O-320.

As far as I know, Vans engine pricing is only available to Vans customers/builders. I don't know if the price is different to someone else. But you're right, my comment was comparing the 916 to a TCd new Lycoming. Those are in the $65-70k range.
 
It is only available to Vans customers with a kit serial number. No clue what the discount is from them.
 
Always good to have options so having Rotax around with their ever more reliable and powerful engines is a good thing … and yes ..anytime we can eliminate mechanical contraptions and replace them with equivalent electronics , it is a win for reliability - I don’t know anyone who longs for good old days where you could patch your carburetor powered car with something on the side of the road and keep going - you can’t do that with a FADEC powered car but you don’t need to as these hardly ever break down - at least compared to their predecessors..
 
anytime we can eliminate mechanical contraptions and replace them with equivalent electronics , it is a win for reliability

Having been around a lot of low volume power and control electronics, that is not my conclusion.

How will you feel about owning certified aircraft power train electronics designed today, made obsolete by their manufacturer 15 years from now, in 30 years?

I don’t know anyone who longs for good old days where you could patch your carburetor powered car with something on the side of the road and keep going

I’d suggest checking Bring-a-Trailer auction sales prices for that kind of cars. The reason is long term value, lack of obsolescence, sustainability directing long term investment. Same as planes.
 
It's almost 100 lbs lighter than a 180 hp and turbocharged so it will keep it's 160 hp nearly all the time. In the real world I bet they would perform nearly the same.

Wrong. It has 160 hp during takeoff, but the continuous horsepower is only 137, a grand whopping total of two extra hp than the 915.
 
Would be nice to replace the narrow-deck IO-320s on the twin comanche.
 
Does anyone know how Rotax rates duty cycle?
EGTs are the limiting factor. I'll give it 100% throttle until 600-800' agl then wind it back to whatever % keeps EGT below 1700.
 
When my O-320 gives up the ghost, the 916 will be a strong contender in my RV-9A. I’m really excited about it. I’ve been watching Vans testing an RV-9 with a 915 for quite some time, and the numbers look really good.
 
Having been around a lot of low volume power and control electronics, that is not my conclusion.

How will you feel about owning certified aircraft power train electronics designed today, made obsolete by their manufacturer 15 years from now, in 30 years?



I’d suggest checking Bring-a-Trailer auction sales prices for that kind of cars. The reason is long term value, lack of obsolescence, sustainability directing long term investment. Same as planes.

You are talking what are basically resell antique markets which by definition are governed by different rules - frankly, if you think about it, GA industry seems like Bring-a-Trailer type of market …. also eerily similar to your typical automobile market in Cuba or what used to be reality in various eastern block countries where the only thing you could get were 50-60 year old car models - not exactly what I would consider a healthy and robust market ….
 
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Would be nice to replace the narrow-deck IO-320s on the twin comanche.
So rated for equivalent of 76% (for a 180hp) power all the time, at any altitude. And weighs 100lb less. I'll take it!

Keep in mind that during takeoff an O360 can't produce full power because it isn't at full RPM. More like 170hp. Above around 2000ft the Rotax is making the same takeoff power.
 
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