How does Rotax do it?

[Tantalum]

As you guys know I'm of the opinion that one of the biggest issues with GA are the pathetic 1940's powerplants we still use. We've covered the whole car engine thing ad nauseam, and have been told on here many times that for reasons X, Y, and Z, that the current crop of Lyco and Conti are the best we'll get

-volume is too low to justify the cost of redevelopment
-FAA certification is draconian, so no FADEC, no ECU, have to use magnetos, have to play 1920s chemist with the mixture control, and do a pagan chant before each engine start
-costs are astronomical
-airplane engines "run at 75% power and thus need to be big and heavy and low RPM"

Somehow Rotax has a found a way to roll out a really badass new engine, in addition to their other bad ass engines, the 915 series, that is absolutely bonkers
-95% power rated for continuous max output
-141 hp
-turbocharged, full sea-level like power until 15,000
-a solid 100 lbs less than a comparable Lyco 360
-1.35 liters!!
-very low fuel consumption
-1,200 hr TBO
-single lever throttle, with electronic controls for fuel, prop, etc.
-two fully independent electrical control systems
-FAA certified, among other certifications

Allegedly at least one of these was swapped out in place of a Lyco-360 180hp and the owner claimed a 10 knot TAS increase as a result of turbo and other refinements

**So if Rotax can do it.. and quite successfully mind you, for a submarket within the tiny GA world, then can we *please* dispel this myth that the legacy Conti's and Lyco's are the best we can put in our planes?

Our Raptor buddy should throw that Audi motor directly in the trash and just slap two of these Rotax 915 on his creation..

https://www.flyrotax.com/produkte/detail/rotax-915-is-isc.html

 

[RyanB]

From a reliability standpoint, it seems as though Rotax have mixed reports.

Their life span <by TBO> is nearly half of what the average Conti and Lyco engine is at 1,200hrs. I credit this to the fact that the internals are spinning upwards of 5,000RPM during cruise flight and nearly 6,000RPM during takeoff, with a gearbox and a turbocharger. That’s a lot of moving parts spinning at high rates of speeds for a long time, just to produce ~140hp.

FADEC might be nice, but let’s face it, for most of us, it’s just not necessary and it adds complications.

As retro as the Lyco and Conti designs might be, their simplicity is hard to beat, while still getting the same performance dollar for dollar.

 

[DaleB]

Rotax has been pretty conservative with TBO over the years. When my 912ULS was built, I think the TBO was 1200 hours. Since then I think there have been two bumps, one to 1500 hours, and the last one to 2000 hours. That one required changing a $20 part. Anyway, I would not be at all surprised to see TBO increased as more field experience is gained. Rotax isn't doing anything magical. They've been building progressively bigger and more powerful engines over a long time, building on experience and advances in materials and processes.

The 912 series seems to be pretty solid, as long as it's operated according to Rotax recommendations. Try to run it like a higher-revving Lycoming and you'll run into problems Ignore their idle speed spec, and you can wear out a gearbox early. Ignore their prop pitch/RPM recommendations, you can have problems. But if you RTFM and follow their practices, you're probably going to see TBO and beyond, from what I'm hearing and reading.

When I bought this plane, it was occasionally balky starting, a little slow in cruise, and the fuel consumption was high. Each problem was solved by simply putting something that had been modified from factory spec, back to factory spec.

 

[Salty]

As you guys know I'm of the opinion that one of the biggest issues with GA are the pathetic 1940's powerplants we still use. We've covered the whole car engine thing ad nauseam, and have been told on here many times that for reasons X, Y, and Z, that the current crop of Lyco and Conti are the best we'll get

-volume is too low to justify the cost of redevelopment
-FAA certification is draconian, so no FADEC, no ECU, have to use magnetos, have to play 1920s chemist with the mixture control, and do a pagan chant before each engine start
-costs are astronomical
-airplane engines "run at 75% power and thus need to be big and heavy and low RPM"

Somehow Rotax has a found a way to roll out a really badass new engine, in addition to their other bad ass engines, the 915 series, that is absolutely bonkers
-95% power rated for continuous max output
-141 hp
-turbocharged, full sea-level like power until 15,000
-a solid 100 lbs less than a comparable Lyco 360
-1.35 liters!!
-very low fuel consumption
-1,200 hr TBO
-single lever throttle, with electronic controls for fuel, prop, etc.
-two fully independent electrical control systems
-FAA certified, among other certifications

Allegedly at least one of these was swapped out in place of a Lyco-360 180hp and the owner claimed a 10 knot TAS increase as a result of turbo and other refinements

**So if Rotax can do it.. and quite successfully mind you, for a submarket within the tiny GA world, then can we *please* dispel this myth that the legacy Conti's and Lyco's are the best we can put in our planes?

Our Raptor buddy should throw that Audi motor directly in the trash and just slap two of these Rotax 915 on his creation..

https://www.flyrotax.com/produkte/detail/rotax-915-is-isc.html

A speed improvement with 40 less horses doesn’t pass the sniff test. Well maybe at 20,000 feet. Also don’t see how you can say “comparable” when the lycoming produces 28% more power and turbo normalization of a Lyco doesnt weigh much.

This is assuming the numbers in your post are accurate.

 

[kyleb]

Rotax makes great replacements or upgrades for the small Continentals. But they don't compete in the 150+ hp class. That's where it falls apart for me. You don't want a 141 hp C-172, Cherokee, Mooney, or RV-whatever.\

If they made a 160 hp engine, I'd definitely consider it for my RV-6 when the time comes. Same for the 250+ hp class for the RV-10.

A couple of things I really like about the rotaxes are that they run on autogas and they are relatively quiet.

 

[Tantalum]

This is assuming the numbers in your post are accurate

I pulled them directly off the rotax site, the link was below in my original post. I'm also not sure what altitude that person who claims he got 10 nops was basing it off of. From 12,000 ft I bet the Rotax with the turbo is cranking out more power than the Lycoming.. in a simpler to operate and lighter package

Seems incredible to me that from 1.35 liters you'll get 141 hp up to 15,000 and be able to run at 95% power all the while not tinkering with mixture and prop settings

TBO is low.. but it is a brand new engine and as we know TBO is just a recommendation. People have needed overhauls as low as 800 hours from not leaning their engine properly, chances are you won't have that issue with this

 

[aftCG]

Not sure I'd expect a change until you cure the Draconian FAA part.

Say, what does a Rotax 915 FWF in a box cost anyway?

 

[Tantalum]

From a reliability standpoint, it seems as though Rotax have mixed reports.

thanks, I think part of that also comes down to rotax being heavily used in applications where owners are flying experimentals, home-built, and other unique applications. I know the volume numbers are different, but I feel like we have almost weekly reports about some plane that goes down for loss of engine power, that recent Mooney comes to mind. I can't actually recall reading about the last rotax powered plane that went down

adds complications.

I don't see how..? your starting procedure is turnkey and you have one lever. ECU's very rarely fail, and with two independent ones on the engine if it does fail you're replacing one part as opposed to troubleshooting a coughing carburetor for a rough running engine, etc., how many people on our own forums complain about various engine anomalies that comes down to some weird mechanical issue in a rube goldberg carburetor setup

same performance dollar for dollar

Not totally, by 12,000 ft that 180 horse Archer is making maybe 55% power, at least based on the poh graphs, and that's assuming optimum performance of magnetos, and optimum leaning. The Rotax is still chooching at 135hp continuous. I guess in some parts of the country that's less important, but where I fly from you will often have to climb to at least 9,000 feet, especially if you are on an IFR plan

Their life span <by TBO> is nearly half of what the average Conti and Lyco engine is at 1,200hrs

DaleB got 2,000 hours out of his rotax and all it needed was a $20 part. He may be an exception, but these numbers seem conservative. And while some people can easily take their Continentals and Lycoming past TBO, there are also plenty of people that are looking at top overhauls etc by a 1,000 hours.. that's assuming their engine did not come from apart in the first five hundred hours


I think it's only a matter of time before we see an even larger 180 horse or 200 horse rotax.. I do believe those will be potential game-changers

 

[Tantalum]

Say, what does a Rotax 915 FWF in a box cost anyway

That's the burning question, along with actual fuel flow figures. Rotax from what I've seen has been hesitant to put those types of numbers out since they depend heavily on owner configurations and what new type of machine the engine is strapped to

Maybe @DaleB would know?

 

[Kenny Phillips]

A speed improvement with 40 less horses doesn’t pass the sniff test. Well maybe at 20,000 feet. Also don’t see how you can say “comparable” when the lycoming produces 28% more power and turbo normalization of a Lyco doesnt weigh much.

This is assuming the numbers in your post are accurate.

Bear in mind that the Lyco only makes its rated power at sea level, certain temps, etc. The Rotax will likely make its rated power anywhere up to a very high altitude. The "underpowered" diesel versions of the 172 outperformed the higher-powered petrol versions. Peak horsepower ain't everything; area under the curve, which can be huuuuge for a properly designed turbo, can change everything.

 

[Kenny Phillips]

Not sure I'd expect a change until you cure the Draconian FAA part.

Say, what does a Rotax 915 FWF in a box cost anyway?

There's no such thing, from Rotax. They don't do FWF. So, you start with $35K for the engine, and add a mount, cowling, etc. So $40K, plus a new prop.

 

[Salty]

Bear in mind that the Lyco only makes its rated power at sea level, certain temps, etc. The Rotax will likely make its rated power anywhere up to a very high altitude. The "underpowered" diesel versions of the 172 outperformed the higher-powered petrol versions. Peak horsepower ain't everything; area under the curve, which can be huuuuge for a properly designed turbo, can change everything.

It was pretty clear that I was bearing that in mind when I said “maybe at 20,000”

 

[kyleb]

Not totally, by 12,000 ft that 180 horse Archer is making maybe 55% power...

The turbo is great at altitude, but that Archer is gonna hit the trees at the end of the runway if it only has 141 horses and has more than two aboard.

As to reliability, a friend carries the airfield name of “bean farmer” because the gearbox on his 912 failed and caused an engine out in a ...bean field.

I like rotaxes, but they are not perfect. From a reliability standpoint, I suspect they are similar to lycontinentals.

 

[Salty]

The turbo is great at altitude, but that Archer is gonna hit the trees at the end of the runway if it only has 141 horses and has more than two aboard.

As to reliability, a friend carries the airfield name of “bean farmer” because the gearbox on his 912 failed and caused an engine out in a ...bean field.

I like rotaxes, but they are not perfect. From a reliability standpoint, I suspect they are similar to lycontinentals.

Exactly.

 

[Dana]

Are the Rotax 91x engines certificated under Part 23 or the ASTM standards for LSA?

Rotax had one big advantage, they were able to leverage their experience building 2-strokes for snowmobiles and the experimental market to learn how to build fast turning geared engines. They had a lot of history on the engines before they ever started the certification process.

Can you imaging Lycoming or Continental selling (as Rotax does) aircraft engines carrying the warning, "this engine may stop at any time"?

 

[Tantalum]

You guys are a tough crowd lol. I appreciate the tech that rotax is bringing us and pushing the envelope on aircraft piston engine advancement

Not advocating a 140 horse engine as a replacement to a 180 Lyco, was quoting what the dude in the video said

I welcome the day someone offers a single lever turn key modern engine

honestly the engines on the diamond da62 are one of the coolest selling points to me, even though the plane is a little goofy looking

 

[Tantalum]

this engine may stop at any time

Looks like part 23, tecnam uses them (912) in there 2006T. Out of 580 built (1,160 engines) there have been 15 accidents I could find, all of these were there loss of control in IMC Gear Up landings, or occurred during training. I couldn't find a single one that was related to engine failure. Not a huge sample size admitted, but these planes live hard lives and the engines have seem to tolerate them well

History has proven that our "reliable" Lycos and Contis have been proven to also stop at any time, and are highly intolerant of poor engine handling by the pilot (ie, running over lean, too rich, etc)

 

[Sac Arrow]

Check out the table in these BFSC numbers. You will find that the Lycosaurs aren't as inefficient as people think they are.

 

[RJM62]

Are the Rotax 91x engines certificated under Part 23 or the ASTM standards for LSA?

Depends on the variant. It's a very versatile engine with at least half a dozen variants that I know of (and probably more). Some are marketed strictly to the UL sector, others to LSA, and others to Part 23; and are certificated (or not) accordingly.

Rich

 

[Tantalum]

Check out the table in these BFSC numbers. You will find that the Lycosaurs aren't as inefficient as people think they are.

Cool table! Thanks! That Junker Jumo 204 knows what's up!

 

[aftCG]

There's no such thing, from Rotax. They don't do FWF. So, you start with $35K for the engine, and add a mount, cowling, etc. So $40K, plus a new prop.

So, basically still Lycosaurus money

 

[Warmi]

Rotax is not exactly new at this game - they have sold something around 180 000 engines since the 70s and they are not exactly cheap either but yeah, it is good to have someone actually trying to push the envelope a bit ... starting at 60 then 80,100,115,140 hp ... slowly but surely inching up and hopefully will keep going

 

[RyanShort1]

I'm just waiting for the day when one can legally swap a Rotax into a Piper taildragger...

 

[GRG55]

Looks like part 23, tecnam uses them (912) in there 2006T. Out of 580 built (1,160 engines) there have been 15 accidents I could find, all of these were there loss of control in IMC Gear Up landings, or occurred during training. I couldn't find a single one that was related to engine failure. Not a huge sample size admitted, but these planes live hard lives and the engines have seem to tolerate them well...

One of the flight training units on our field had three P2006 twins in their fleet. Five of the engines didn't make it even 1/2 way to TBO (these are naturally aspirated Rotax engines - 100 hp 912 I believe). All were sent to a Rotax facility and after tear down Rotax wrote them off. Rotax said you should avoid running the engines on 100LL, and if you must there is a much reduced oil change interval. Rotax would not entertain a warranty claim. We don't have mogas on our field. That was the official line from Rotax, and the whole thing ended up the subject of a lawsuit with the company maintaining those airplanes. The training academy sold the airplanes to someone in South America and replaced them with Seneca IIs.

History has proven that our "reliable" Lycos and Contis have been proven to also stop at any time, and are highly intolerant of poor engine handling by the pilot (ie, running over lean, too rich, etc)

I will dispute this statement. How many Lycoming and Continental engines have been the subject of abuse from ab initio students over the many, many decades they have been powering planes? They are anything but "highly intolerant" of abuse.

As you guys know I'm of the opinion that one of the biggest issues with GA are the pathetic 1940's powerplants we still use. We've covered the whole car engine thing ad nauseam, and have been told on here many times that for reasons X, Y, and Z, that the current crop of Lyco and Conti are the best we'll get

-volume is too low to justify the cost of redevelopment
-FAA certification is draconian, so no FADEC, no ECU, have to use magnetos, have to play 1920s chemist with the mixture control, and do a pagan chant before each engine start
-costs are astronomical
-airplane engines "run at 75% power and thus need to be big and heavy and low RPM"

Somehow Rotax has a found a way to roll out a really badass new engine, in addition to their other bad ass engines...

...**So if Rotax can do it.. and quite successfully mind you, for a submarket within the tiny GA world, then can we *please* dispel this myth that the legacy Conti's and Lyco's are the best we can put in our planes?

...

Good on Rotax. I don't dispute we need some new thinking and new product in this space. But don't expect a whole lotta followers. Rotax makes a huge number of recreational product engines every year - anything but a pure airplane engine maker - and there is no doubt the aircraft engines benefit from the cross pollination of metallurgy, turbocharger research, manufacturing methods and so forth.

But I just bought a little taildragger a short time ago, and no way would I switch from the 180 hp Lycoming to an identical plane with a Rotax, if such existed.
But I am looking closely at Bombardier's just announced 2020 sleds, with an eye on one with the 850 E-TEC 165hp Rotax 2-stroke.

 

[Warmi]

So you are saying that it’s on Rotax that whoever was maintaining these engines was not following the very basic guidelines that every Rotax owner that I know seems to be aware of - if you run leaded fuel more than 30% , your oil change intervals are halved and so is your gearbox maintenance interval ?

 

[mondtster]

Looks like part 23, tecnam uses them (912) in there 2006T. Out of 580 built (1,160 engines) there have been 15 accidents I could find, all of these were there loss of control in IMC Gear Up landings, or occurred during training. I couldn't find a single one that was related to engine failure. Not a huge sample size admitted, but these planes live hard lives and the engines have seem to tolerate them well

The Rotax was also used and certified on the early Diamond DA-20. Diamond went away from them for a Continental engine after a few years though.

History has proven that our "reliable" Lycos and Contis have been proven to also stop at any time, and are highly intolerant of poor engine handling by the pilot (ie, running over lean, too rich, etc)

Aircraft engines are anything but fragile. They're simple and almost always run, even when abused or when they're not running right. As was noted above, they were purpose designed and are actually quite efficient at what they do. There is room for improvement/modernization however.

Unfortunately, one of the problems with modernization and/or totally new engines is the lack of airframes that they are approved to be installed on. People often complain about the "ancient technology" on these aircraft engines but forget that they're flying airplanes built 40+ years ago. Take a look at the automotive technology from the 1960s and 1970s and it starts making more sense as to why things are the way they are. The only people who really have room to complain are the people buying new or nearly new airplanes - it really seems to me like a 2000+ model year airplane should have similar systems and operation to that of a similar model year car. We're not there yet however, and those improvements really wouldn't improve the already good efficiency of the engines.

 

[Warmi]

Predator UAVs we’re equipped with Rotax 914 engines as well ( 115 hp )

 

[Tantalum]

it really seems to me like a 2000+ model year airplane should have similar systems and operation to that of a similar model year car.

that's a great point, and the fact that the actual aircraft themselves outside of what Garmin has offered haven't advanced at all since the 1950s (one could argue they have gone backwards as today's offerings of the planes that were around in the 1950s, IE Bonanza, have less useful load) is why people simply aren't buying new airplanes when the used market has excellent offerings for a fraction of the cost. Cirrus, as no surprise then that they are selling new airplanes, partially because they haven't been around since 1950, and because they're actually offering something that's sort of feels like you're modern car equivalent. I bet by 2030 Cirrus will be selling few piston aircraft

 

[mondtster]

that's a great point, and the fact that the actual aircraft themselves outside of what Garmin has offered haven't advanced at all since the 1950s (one could argue they have gone backwards as today's offerings of the planes that were around in the 1950s, IE Bonanza, have less useful load) is why people simply aren't buying new airplanes when the used market has excellent offerings for a fraction of the cost. Cirrus, as no surprise then that they are selling new airplanes, partially because they haven't been around since 1950, and because they're actually offering something that's sort of feels like you're modern car equivalent. I bet by 2030 Cirrus will be selling few piston aircraft

I think the real reason why people aren't buying new or newer aircraft is because new ones are priced too far out of the average guy's reach and there are too many cheap old airplanes that are "good enough". If we didn't have all these "good enough" airplanes there might be fewer people flying but those who are would certainly be looking at newer equipment. I maintain a small fleet of airplanes for a friend which consists primarily of airplanes less than 20 years old with low time but there are a few 50ish year old planes in there too and despite the complexity the new planes require far less work and generally aren't used up like the old stuff is (and his old airplanes are nice - not the typical junk you see on the ramp).

Regarding advancements in recent years, I agree in some ways and disagree in others. There have been subtle advancements with the newer engine designs and manufacturing processes. Just like in the auto and motorcycle industry things as simple as the materials used and the castings are have improved immensely but we're still not there yet. The Europeans seem to be beating us at the aviation game when it comes to new airplane designs getting certified. In my opinion, the Diamond is the cream of the crop when it comes to design and manufacturing fit and finish.

 

[Stan Cooper]

I thought the airworthiness standard for aircraft engines was 14 CFR Part 33, not Part 23.

https://www.govinfo.gov/app/details/CFR-1999-title14-vol1/CFR-1999-title14-vol1-part33 AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES

https://www.govinfo.gov/app/details/CFR-2011-title14-vol1/CFR-2011-title14-vol1-part23 AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES

CERTIFICATION BASIS 14-CFR, part 33, Airworthiness Standards: Aircraft Engines, effective February 1, 1965, as amended by 33-1 through 33-15, inclusive, including Federal Aviation Administration Special Condition, NPRM Doc. 24922, Notice 92-14.

The Austrian aviation authority, Austro Control GmbH (ACG), originally type certificated this engine. The FAA validated this product under U.S. Type Certificate Number E00051EN. Effective September 28, 2003, the European Aviation Safety Agency (EASA) began oversight of this product on behalf of ACG.

IMPORT REQUIREMENTS To be considered eligible for installation on United Sates registered aircraft, each new engine to be exported to the United States with ACG or EASA airworthiness approval shall have a Joint Airworthiness Authority (JAA) or EASA Form 1, Authorized Release Certificate. The JAA or EASA Form 1 should state that the engine conforms to the type design approved under the U.S. Type Certificate E00051EN, is in a condition for safe operation and has under gone a final operational check.

http://rgl.faa.gov/Regulatory_and_G...8b66b86258050006bb696/$FILE/E00051EN_Rev6.pdf

 

[GRG55]

So you are saying that it’s on Rotax that whoever was maintaining these engines was not following the very basic guidelines that every Rotax owner that I know seems to be aware of - if you run leaded fuel more than 30% , your oil change intervals are halved and so is your gearbox maintenance interval ?

As usual in these sorts of circumstances the actual situation was a bit more nuanced than this.

 

[Salty]

I think the real reason why people aren't buying new or newer aircraft is because new ones are priced too far out of the average guy's reach and there are too many cheap old airplanes that are "good enough". If we didn't have all these "good enough" airplanes there might be fewer people flying but those who are would certainly be looking at newer equipment. I maintain a small fleet of airplanes for a friend which consists primarily of airplanes less than 20 years old with low time but there are a few 50ish year old planes in there too and despite the complexity the new planes require far less work and generally aren't used up like the old stuff is (and his old airplanes are nice - not the typical junk you see on the ramp).

I never knew anyone in aviation, all I saw was the prices for new aircraft, so I thought it was out of reach. When someone told me they bought a mooney for $20,000 that could seat 4 and had a range over 500 miles I looked closer and within 6 months I had my license and within a year owned a plane (that was 50 years old, but only had 2500 hours on it)

 

[Warmi]

I never knew anyone in aviation, all I saw was the prices for new aircraft, so I thought it was out of reach. When someone told me they bought a mooney for $20,000 that could seat 4 and had a range over 500 miles I looked closer and within 6 months I had my license and within a year owned a plane (that was 50 years old, but only had 2500 hours on it)

Thats not a feature .. you are basically doing the same thing that car owners do in Cuba - they drive 50-60 year old cars because they cannot afford anything newer so the whole place looks like some kind of odd relic from the 50s.
Exactly the same as your average GA airport.

In Cuba it is due to idiotic economic policies , in the US it is probably a similar reason ( FAA) but the end effect is the same - time pretty much stands still and there is no progress.
Again, it is not a sign of a healthy and robust sector ... probably the only sector in this country that closely mimic communistic economy pathologies ...

 

[Sac Arrow]

Thats not a feature .. you are basically doing the same thing that car owners do in Cuba - they drive 50-60 year old cars because they cannot afford anything newer so the whole place looks like some kind of odd relic from the 50s.
Exactly the same as your average GA airport.

In Cuba it is due to idiotic economic policies , in the US it is probably a similar reason ( FAA) but the end effect is the same - time pretty much stands still and there is no progress.
Again, it is not a sign of a healthy and robust sector ... probably the only sector in this country that closely mimic communistic economy pathologies ...

Off topic, but Google Earth tells a different story about Cuba. You see modern roads and buildings, mostly new cars, and lots of restored 50's vintage cars. I don't know about their economic policies, but tourism is big there. Just not from the US. I think that description was probably true up to the point where the Soviet Union dropped their economic support for Cuba.

 

[G-Man]

The Cuban cars may mostly look like vintage 1950s cars, but most of them have updated drivetrains - typically mid 80s or 90s turbodiesel truck systems.
Warmi's analogy holds to a certain extent, but the cars are only kept running through more Experimental-like, unregulated, adaption and enhancement.

 

[GRG55]

Thats not a feature .. you are basically doing the same thing that car owners do in Cuba - they drive 50-60 year old cars because they cannot afford anything newer so the whole place looks like some kind of odd relic from the 50s.
Exactly the same as your average GA airport.

In Cuba it is due to idiotic economic policies , in the US it is probably a similar reason ( FAA) but the end effect is the same - time pretty much stands still and there is no progress.
Again, it is not a sign of a healthy and robust sector ... probably the only sector in this country that closely mimic communistic economy pathologies ...

I wonder if the repeated comparisons I see on this forum between autos and aircraft are all that valid.

First, the FAA isn't standing in the way. The rules are well known and documented. And every time some nitwit GA pilot flies his perfectly good airplane into the dirt we re-learn the lesson there is no public support for the FAA to relax those rules - quite the opposite, in fact. No manufacturer need guess at what is required. And if Cirrus is indeed, as some suggest, "the most advanced single engine piston airplane ever made", where's the evidence the FAA is an impediment to improvement?

The FAA has been remarkably lenient over time, compared to what the auto industry has been subjected to. The ADS-B mandate, which raised so many howls of protest, is small beans compared to what has been mandated over the decades for the auto industry. Which of the two has really been the greater subject of a "communist economic pathology"?

The reason so many vintage GA airplanes are still flying is probably due to to the fact aluminum airframes have proven quite durable (compared to their ferrometallic auto equivalents) and their modern replacements don't offer much additional utility for the cost.

Compare a Cirrus SR-22 with the plane it largely replaced, the Bonanza. Four adults clamber over the wing, get settled in a 2 & 2 configuration, latch the door(s), fire up a 300 hp air-cooled engine and head off to cruise at about 180 kts at 12,000 +/- ft. It might be made of plastic, and it might be marginally faster, but it's not really all that big an advance in utility from a 35 year old A36 Bo.

The point is a clean sheet, 4-adult single piston engine airframe design today isn't going to look much different or offer much more usefulness as an airplane than its comparable decades old predecessors. And the gap gets even narrower with the multiple options to Garminize the old geezer.

(And most of us feel no need to pay up for side-yokes, Beringer brakes and LED convenience lighting).

 

[Juliet Hotel]

I keep wondering when Rotax will do a 6-cylinder version of the 9xx series.

 

[455 Bravo Uniform]

I’ve heard of only 2 engine-outs (complete shutdowns) on planes based at my field since I’ve hangared here (2 years). One was a new diesel 172 and the other was a Rotax powered experimental. Both landed out safely in farm fields.

The few other engine problems that I know about have all been Conti/Lyco problems (running but making crap power, or before TBO tear downs). No dead-sticks.

There is only one diesel that I know about on the field, and a couple experimentals (not sure of power plants), with the rest Conti/Lyco.

Data points, no conclusions.

 

[weilke]

Engineering, testing and skillfully working the regulatory aspects. That's how they do 'it'




A 250hp Rotax would be a game changer.

 

[mondtster]

A 250hp Rotax would be a game changer.

Only if provisions were made to install them on airframes that were originally certified with something else on them. In other words, an STC.

Lycoming had the modernized IE2 engine that went nowhere because no airframers were interested and there were no STCs for them.