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Is Rotax Planning a New Engine?

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Does general aviation need new piston engines? Well, sure, it always does, but thatís not the same as saying it can sustain new engine designs. Nor does it stop companies from telling the R&D department to push around some ideas. In business in general, we call this progress, while in general aviation, itís known as hallucination. (Sorry, I couldnít resist.)

One rumor thatís sort of circulating is that Rotax is about to release a new engine to compete with Lycomingís mid-horsepower line. If you break this down a little, it makes sense that the rumor is true. After all, Rotax is a big player in the engine business and no company can stand still and expect to survive, much less thrive. So Iím sure Rotax is always considering new ideas. Now whether theyíre on the cusp of announcing something soon is another matter. But the pieces align for Rotax in interesting ways.

The 100-HP 912 iS they announced 20 months ago has been well received and itís finding its way onto a lot of LSAs; the experimental market will come along eventually. Weíre not talking large volumes here, but Rotax never figured on that. It will build into a sound business. Consider that the 912 iS gives Rotax a strong basic platform in certifiable electronic engine control and fuel injection applied to a light, reliable engine with a good reputation. For cert purposes, theyíve done the hard part in the electronics package. The engine rotating stock is simply a matter of scaling what they already understand.

What horsepower? How about the basic 912 iSówith its new crankcaseóinched up 125 to 130 HP to compete with Continentalís IO-240 in a lighter, more sophisticated package? One source I know in the LSA business says thatís what heís heard. The 240 doesnít have much market penetration because itís too heavy for LSAs and airplanes like the DA20 arenít selling well. But you can see how an up-powered 912 platform would be a nice addition to a next-generation LSA. Buyers will pay for higher horsepower and performance.

The sweet part of the market is 150 to 180 HP where the Skyhawks and Archers live. And Iím not thinking of those airplanes specifically, but airplanes like them that appeal to that market slice. The Tecnam P2010 is one. Itís a 172-like platform, but more modern, with better useful load and performance. The airplane is equipped with a Lycoming IO-360 thatís relatively efficient, but still old school. If a Rotax four- or six-cylinder engine in the same power range delivered numbers similar to the 912 iS, it would be 15 to 20 percent more efficient for the same or perhaps less weight. Thereís no reason Rotax couldnít get there; all it takes is the will and sufficient investment capital. The cold dash of reality might be that the market just isnít robust enough to support such an investment, so it might be perfectly rational to give it a pass. Itís technically doable in some form, if economically risky.

But Rotax surely isnít risk averse. While the 912 iS is a careful, incremental improvement on the 912, recall that in 2003, Rotax, under different management, stunned everyone by announcing a pair of V-6 engines in the 220- to 300-HP range. On paper, these engines were what buyers claimed they wanted: cutting edge technology, powerful, smooth and, well, just different. The company, then owned by Bombardier, which championed the project, found OEM takers in Cirrus and in Piper. Alan Klapmeier once told me Cirrus was ready to go forward with the V-6.

But for various reasons, not the least of which may have been management change and technical issues with the engine, the project was dropped in 2006. It was probably just as well. Compared to traditional aircraft engines, the V-6s were complex and heavy and not that fuel efficient. They also werenít intended for 100LL, but mogas or a mogas-like fuel. In 2005, with legacy aircraft as a base, I doubt if Rotax would have found sufficient volume to justify the investment and if they had complaints from customers and OEMs about finding service shops for the smaller engines, the larger ones could have been a nightmare, especially for an overhaul network.

But things change. Even though we hear occasional complaints that mechanics canít fix Rotax engines, we hear fewer of them because, well, mechanics have learned to fix Rotax engines. While light sport hasnít turned the sky dark with aircraft, Rotax 912s arenít exactly seldom-seen exotica anymore. If you think of them as motorcycle engines, theyíre not difficult to maintain. Moreover, the lock Lycoming and Continental have on the market with traditional aircraft engines is compelling, but it canít last forever. Sooner or later, the worm will turn toward a new niche. New airframes, designed and built under the revised Part 23 initiative, will come along.

Diesels have been getting all the ink lately, but itís a mistake to assume that this will stunt gasoline engine development entirely. It hasnít done that in automotive and it wonít in aviation, either. Rotaxís expertise is in sophisticated, economical recreational gasoline engines. I wouldnít expect them to venture into heavy fuel design, although the larger horsepower definitely takes them out of their recreational-engine comfort zone. But not much, given that airplanes that require that horsepower are just recreational vehicles by another name. A company that makes snowmobile and motorcycle engines doesnít have the same aviation chops as Continental or Lycoming. But thereís no reason it canít develop this expertise.

One area in which Rotax has a leg up on other manufacturers is environmental sensitivity. When we were at the Rotax factory in 2011, conversations were peppered with discussion about noise, fuel efficiency and emissions. Itís clear that Rotax senses its recreational engines will be targets as world concerns about greenhouse gas emissions intensify. Rather than denying that reality, Rotax wants to be ready with products that are at least perceived as being greener. Not for nothing does the 912 iS have an ďecoĒ mode.

Itís anybodyís guess whatís going on inside the warrens at Rotaxís Gunskirchen skunkworks, but it seems to me the company is well positioned to announce something surprising. Itís not a question of if, but when.

Join the conversation. †Read others' comments and add your own.

Comments (15)

I've seen too many Rotax products fail (yes, all were on Aircraft), so unless they GIVE me one, I'll stick to my trusty Lycoming and accept that it's not as fuel efficient, and might harm the ozone layer a little more. However, I think my LIFE is worth it.

Give me one...nah, I might take it, but I'm not strapping it on ANYTHING where I'm the PIC. I'll sell it on eBay.

Posted by: R. Doe | December 1, 2013 6:38 PM    Report this comment

"Diesels....it hasn't done that in automotive and it won't in aviation, either" I take you never leave the USA?? Diesels are everywhere in Europe and Asia.

Posted by: Ken McKenzie | December 2, 2013 8:52 AM    Report this comment

I travel quite a bit to europe and, while diesels are certainly much more common in Germany, they are not dominant. I probably only get a diesel as a rental 20% of the time.

Posted by: TAMI MORRISON | December 2, 2013 9:18 AM    Report this comment

In 1998 I put quite a bit of rental time in a Diamond Katana, powered by a Rotax engine. And I loved them both: the plane was like a little sports car, complete with stick controls, and the engine was as smooth as the proverbial baby's bottom. Plus, it was nice to see some NEW technology in a field dominated by 1970's model Piper Warriors with their slow turning, heavy vibrating thump-thump-thump lawn tractor motors.

That said, just because *I* liked it, doesn't mean others will, too. Plus, as a renter, I didn't have to worry about such matters as maintainence and overhaul. Plus, the market for new engines in new airplanes isn't exactly huge. So, while I wish Rotax well in their endeavours, whether they will succeed or not is hardly an easy thing to guess.

Posted by: Eric Gudorf | December 2, 2013 10:48 AM    Report this comment

I think Lycoming and Continental better pay attention; and I think they are.

Posted by: Stephen Phoenix | December 2, 2013 12:30 PM    Report this comment

I've seen too many Lycoming and Continental products fail (yes, all were on Aircraft), so unless they GIVE me one, I'll stick to my trusty Nike sneakers and accept that it's not as time efficient to walk everywhere. However, I think my LIFE is worth it.

Give me one...nah, I might take it, but I'm not strapping it on ANYTHING where I'm the PIC. I'll sell it on eBay.

Posted by: John Clear | December 2, 2013 12:56 PM    Report this comment

John Clear, I love your response to R. Doe. I fly behind a continental about 120 hours each year and the cylinders are always something that worry me. I topped them 830+ hours ago and have had three of the four off for various problems over the past six years. My mechanic told me in October during my annual the fourth one is coming off next year. I have not spoken to anyone who flys behind a 912 100 hp Rotax that regrets it. I'm not happy about the mandatory hose replacement every five years but, maybe that's not a bad thing and should be a consideration for all engines. My next engine will be a 912 or 912 IS. Call me paranoid but I have very little faith in a replacement for 100LL or "Mogas" being brought into my airport. So, it will be off to the corner station to get my car gas with 10% ethanol as I fly in the future with a new airframe and engine.

Posted by: jay Manor | December 2, 2013 6:41 PM    Report this comment

I didn't think the high-revving Rotax engines nor their gearboxes were going to cut it but I was wrong. I'd prefer one of them to the sweet looking Jabirus from my neck of the woods, which, despite being simpler, don't appear to be as reliable.

Given what Tecnam has been able to do with two 914s on the P2006T, it got me wondering what could be done with them on a more sporty kit or certified aircraft. Maybe something between an MCR-01 and an RV? A zippy 230hp, 4 seat twin with big, effective flaps and the same fuel burn as a C172 could be getting close to the ultimate personal aircraft. Hang on, I think I just saw Elvis! What was Bertorelli saying about hallucinations?

Posted by: John Hogan | December 2, 2013 9:11 PM    Report this comment

Over the past couple of years the new engine launches in motor cars (outside U.S. have all been small (around 1000cc) three cylinder, mainly but not exclusively, gasoline engines with turbos, exhaust filters and fancy electronics. Power is between 65 hp and 120 hp, depending on the electronic settings and use of stronger or weaker crankshafts, mainly. Ford (in Europe) is on record as saying once they started down this line they realized that they were saving so much weight, they decided to scrap the original play of having an aluminium block and just go with good old cast iron, because otherwise the front of the car would be too light. In most uses in cars this engine weighs in at 100 kg. Make something similar in alu, with around 1,500 cc with electronics optimised for flight and you might be on a winner in the 180 HP market-- except most aircraft are in the US where hostility to innovation in engine design, especially foreign innovation in engine design means it is hardly worth it. My bet is they are looking at electric motors, where the most common designs were designed in the 1920s, but where new washing machines have shown the potential for great efficiency savings by moving away from coils, brushes and magnets. After all, from go-ahead to an idea to a factory producing motors, is at least 10 years, and by then some of the money thrown at batteries might have stuck. I mean, who would have thought people would be willing to pay $100 for extra bright rear bicycle lights which you recharge through a computer USB port?

Posted by: John Patson | December 3, 2013 5:18 AM    Report this comment

The V-6 (really just the 300; no one wanted the 220hp normally-aspirated version) was pulled for reasons of certification. Specifically, its advanced ignition/fuel mapping software and electronic module construction themselves were impossible to adequately explain to the FAA. That may be moot by now, though.

The other engineering faux pas (although I later found out it was mandated by marketing, which explains it) was the exact 3:1 gearbox. One tooth either way (I believe it was 12t:36t) would have allowed same tooth-pair contact every 40-45 seconds; with exact 3:1, contact (at 6000rpm) occured every half-second. or so. This dictated heavier gears and portended strange harmonics.

Nevertheless, initial tests (Piper, Cirrus, and the Murphy Moose -- whatever happened to that plane?) of the V-300 were promising, and wear tests were good, as well. I hope they can make something of all this preliminary work.

As for the dominance of legacy designs, there are good reasons why they still dominate, though some obvious improvements (e.g., intake design on the 360s) aren't economically feasible, due to the expense of certification and small sales volumes.

Posted by: Tim Kern | December 3, 2013 12:30 PM    Report this comment

AvWeb has a habit of censoring inconvenient truth but here goes.

NO ONE singing the praises of Rotax seems to EVER spotlight the simply hilarious/hideous maintenance and operational complexities of the 912, etc Maybe they are all mechanics or handy with lots of time... or not, but with lotsa money... but water cooled Rotax 4 strokes and even fussy 2 strokes are a FAR cry from Lyc/Cont simplicity.

Following the Rotax ops and maint manuals will have you doing half hour engine preflights burping, measuring, checking multiple reservoirs in precise sequences, eyeballing seals and hands0n security checks of fasteners IF you can do them at all since poorly designed/engineered aircraft like Sport Cruiser (at least original series) didn't provide access to comply without removing entire cowling.

The Teutonic precision maintenance incorporates layers of synchronizing, shimming, replacements NEVER a part of "check oil, turn key, go fly, do annual" Lyc/Cont ownership... and the frequent service bulletins and parts prices ?!?! FUGGEDABOUTIT

The elegant Jab 6 cyl is my choice in the lightweight mid power range and NO properly installed it does NOT overheat and without unapproved crank extensions it does not clank to a stop.

Posted by: Allande Corvette | December 3, 2013 12:54 PM    Report this comment

I wonder if Rotax is eyeing the success UL Power is having with their line of engines. http://www.ulpower.com/

Posted by: Stephen Kearney | December 3, 2013 4:48 PM    Report this comment

Allande, Paul specifically mentioned maintenance issues. They started as a finicky, unknown quantity for mechanics but that has changed. The Jabirus should eat them but they still have question marks over the heads/valves and how long they'll go before overhaul. I did my rec licence behind one and loved it but the instructor, who is very conservative and who operates less than an hour of the factory, said you shouldn't expect to get close to TBO. If that changes, Jabiru could rule the world.

Posted by: John Hogan | December 4, 2013 6:29 AM    Report this comment

Allande, Paul specifically mentioned maintenance issues. They started as a finicky, unknown quantity for mechanics but that has changed. The Jabirus should eat them but they still have question marks over the heads/valves and how long they'll go before overhaul. I did my rec licence behind one and loved it but my instructor, who is very conservative and who operates less than an hour of the factory, said you shouldn't expect to get close to TBO. If that changes, Jabiru could rule the world.

Posted by: John Hogan | December 4, 2013 6:31 AM    Report this comment

What someone needs to do is make a Wenkel Rotary engine for aircraft. They are kindof a compromise between a reciprocating engine and a turbine and would be more reliable than a conventional recip. http://www.towerhobbies.com/products/os_engines/osmg1401/osmg1401_550.jpg

Posted by: Randolph Rostie | January 6, 2014 11:30 PM    Report this comment

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