Capt.Crash'n'Burn
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That would make Hugo Junkers a greater visionary than history has given him credit for. :wink2:
Stupid engine question.
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That would make Hugo Junkers a greater visionary than history has given him credit for. :wink2:
Capt.Crash'n'Burn
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http://www.traceengines.com/
It's been around for a long time. Orenda developed IIRC over 15 years ago. They built it to replace the lower HP PT-6 & TPE-331 turbines in the King Airs and Aero Commanders. It never really caught on. It has become a factory power option for the 400 series Air Tractors. A year or so ago I saw an Aero Commander with them up for sale, not sure what the certification status was on the aircraft.
Trapper John
Ejection Handle Pulled
The Trace engine is what used to be the Orenda, right?
If diesels are the future, I hope they do better than Theilert...
wanttaja
En-Route
"Just"? Not hardly.
I've looked extensively at accidents involving of automobile conversions in homebuilt aircraft. The contention that "auto engines aren't as strong internally" is wrong. Auto-engined homebuilts have a lower rate of incidence of internal failures such as rods, crankshafts, etc.
They generally fall down in the accessories department...ignition systems, Propeller Speed Reduction Units (PSRUs), radiator systems, and other hardware related to liquid cooling. About 4.5% of LyCont engine failures are due to the ignition system, vs 18% of the auto engine conversions. LyConts *do* have cooling problems...but once they're solved, they generally STAY solved (e.g., baffling doesn't deteriorate much over time) vs. a liquid-cooled engine developing leaks in the hoses, pumps, and radiator over time.
There's no way to tell how many auto-engined aircraft are in the US fleet, so there's no reliable method to determine what the accident rate is for them, vs. traditional engines...30% of homebuilt registrations don't identify the engine type. But I've looked at the accidents themselves. About 12% of homebuilt accidents involving "traditional" engines were due to a problem with the engine, vs. about 36% of the auto-engined homebuilts. This is NOT a "Three times higher accident rate" as some people interpret it...but it does indicate that auto engines generally do not have the reliability of traditional engines in an aviation application. I've attached a section from an EAA presentation where I show the results of my study.
The basic problem is the baseline. A homebuilder using a Continental can certainly botch the installation, set up the engine wrong, or install an accessory (such as an electronic ignition) that is never going to work right. But he or she is starting with a unit that has an established reliability in an aviation application. For examples on how to install it, cool it, provide fuel to it, and provide spark to the cylinders, he has to look no further than the typical Cessna.
There's no baseline in the auto-engine conversion world. For every careful converter like Ben, there' someone who drags a dead Chevy home from the junkyard, buffs the engine clean with an oily rag, and declares that all he has to do is weld together an engine mount and hang the radiator.
If you want a reliable auto-engine conversion, there are several companies who will sell you one...set up, ready to install, just like a Lycoming comes from the factory.
The key factor, of course, is that they COST as much as a new Lycoming.
The key equation for auto-engine conversions:
Cheap, Reliable, and Light. Pick any two.
Ron Wanttaja
Capt.Crash'n'Burn
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Thanks for the input Ron. I had no idea that there was such a high failure rate of ignition systems. Since I've seen so few problems with newer electronic units (post 1990) It didn't cross my mind. The MSD 6AL unit that Ron uses seems like a pretty good piece though. I've used 'em myself in racing applications. They're bullet proof IMO.
Yep, we used to run a pair of 280 hp Chevy 409 blocks in a 38' Sport Fisherman at 2700 rpm low cruise and 3000 high cruise. At 2200 hours all was well. Next owner never made 2500.....
-Skip
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Dan Thomas
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When I was a young buck in high school my Power Mechanics teacher told us that 90% of engine problems would be electrical. In the 40 years since, I have found that he was 100% right. Carbs and fuel systems don't make anywhere near the trouble that ignition does (other than carb icing, which is not a mechanical issue but a pilot training issue) but the fuel system is often what is first blamed when an engine acts up.
The ignition failure rate is the reason we have two magnetos, and the reason we use magnetos is that they don't rely on the aircraft's electrical system, which, as my teacher would say, will produce 90% of the trouble. Sure, there are uncertified self-contained magneto replacements and sooner or later, if they get certification, Lycoming and Continental will buy them. The magneto manufacturers have been screwing up recently---Slick has had quality control problems and TCM/Bendix, aside from the long AD history, has now dropped the dual mag---and the engine manufacturers will look hard at anything that improves the warranty situation. But to say that Lycoming and Continental are dinosaurs isn't fair; they aren't about to use some ignition system that will fail completely, like a car's will, when the alternator quits or some other critical component fails. They'll keep using mags until something that's actually better comes along. They've been watching Thielert, like most of us, and have seen the accidents and ADs arising out of the electrical supply failures to the FADEC system, which allowed perfectly fine engines to go to idle and stay there when the bus voltage dropped very briefly below 9 volts or so. Is that what we want on our airplanes? Don't think so. Got to do better than that, and got to make money somehow on a very small market while doing it. I don't envy anyone who tries.
Dan
That's not 100% accurate... we have 2 mags because we need 2 mags to run properly. When you do a mag check, you get an RPM drop right? It also gives us a redundant "limp home" mode, but that is not the primary function of dual mags.
Capt.Crash'n'Burn
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Rich AF ratios actually combined with the large bore/combustion chamber/low CR. Most people never run lean, they've been told not to so they use fuel for cooling rather than air.
The Junkers Jumo was an excellent engine, some of the very efficient big diesels in container ships are opposed piston engines. The Jumo was heavy though and big. If we could scale it down to put in our small aircraft, it would be great, but you have to make it a 6 cyl/12 piston to dampen the power pulses.
RMCN172RG
Pattern Altitude
Dual mags, and dual plugs give both a better and a more even fuel burn in the cylinder.
jhausch
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jhausch
I hope these guys get traction:
http://www.dair.co.uk/
http://www.jetwhine.com/2009/08/airventure-update-gemini-diesel-engine/
http://www.ppdgemini.com/
http://www.dair.co.uk/
http://www.jetwhine.com/2009/08/airventure-update-gemini-diesel-engine/
http://www.ppdgemini.com/
Capt.Crash'n'Burn
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I'm sure it can be done with a single plug (especially with a 4 valve head) if you invested in some combustion chamber R&D work but I like the idea of redundancy.
Capt.Crash'n'Burn
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Doggtyred
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And even more so.. the reliability and durability of the accessories you add onto the converted block. A water pump or alternator can put you in the ground just as quick as a blown engine.
And the workmanship and hardware needs to be racing grade/aircraft grade, not just ordinary automotive grade.
Safety wire, locking nuts and the sort are practices that came in to fashion as a result of the blood of others.
And this is coming from someone who believes in automotive power for aircraft, but has done due diligence.
Basically, they just scaled down the Junkers Jumo engine.
No, none of those are like a Jumo. A Jumo was an opposed pison engine in that it had 2 crankshafts on the ends of the cylinders and the pisons came together in the middle forming the combustion chamber. These are all horizontally opposed "boxer" engines as are typical small aircraft engines.
The Gemini IS an opposed piston 2-stroke concept.
Capt.Crash'n'Burn
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Yeah, what weilke said. Take a close look at it. It's a 2 cylinder, 4 pistion, twin crank, 2-stroke diesel.
That must be the last one. I didn't see it because for some reason Firefox on this computer has an issue with opening PDF pages.
Dr. O
Pattern Altitude
The Orenda engine guys are at it again (under a new name that escapes me at the moment)... This is aimed at replacing the quarter million dollar PT6 turbine, primarily in crop dusters... It certainly is not at a price level that you and I are likely to find appealing or affordable... The TBO is currently 1500 hours... One outfit has two of them flying that have run a total of 1600 hours together... Apparently maintenance has been minimal so far... But again, the purchase price with the PSRU box and accessory drive box will knock your socks off...
OTOH, the direct drive Lyc's on my 58 Apache have 6400 hours (1957 engine) and 5800 hours (1960 engine), respectively, with the usual field overhauls along the way...And the original crankcases, rods, cranks, and cams/lifters, and accessory drives, show no signs of failing and these parts should continue on running until long after I am dead and gone...
denny-o
OTOH, the direct drive Lyc's on my 58 Apache have 6400 hours (1957 engine) and 5800 hours (1960 engine), respectively, with the usual field overhauls along the way...And the original crankcases, rods, cranks, and cams/lifters, and accessory drives, show no signs of failing and these parts should continue on running until long after I am dead and gone...
denny-o
Dan Thomas
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Exactly right. I fly an A-65 that was built in 1946. I don't imagine too many guys who had anything to do with building it are still alive. Some may call these established aircraft engines Lycontisaurs but they go and go, while the auto conversion guys are on the ground tinkering endlessly. I've been there and done the auto engine thing and am old enough now that I wouldn't want to waste any more years doing it again. I find it interesting, but not worth the huge layout in money and time and frustration.
Dan
When Toyota throws a full multi million dollar program at it for several years and gives up because they couldn't make it as reliable as the Lycoming on the other wing of their nail polish red Aztec, nor as fuel efficient, that should say something right there.
Capt. Geoffrey Thorpe
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Yea, they should have let Ford do it.
Yea, they should have let Ford do it.
Hey...... be nice.... :wink2:
I drive a Toyota and fly a Ford...
Dan Thomas
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Yup. And Mazda and John Deere fooled for some time together on an aircraft rotary engine. IIRC, Honda also messed with a piston aircraft engine. Didn't work out. There have been other professional attempts at converting existing auto engines, too. All of them rely on PSRU technology and rather high engine RPM, both of which introduce problems absent in the direct-drive "Lycontisaurs." The Lycomings and Continentals that are/were geared have had PSRU issues, too.
Dan
Capt.Crash'n'Burn
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It would be my suspicion that Toyota gave up on it because they figured that they couldn't make money at it.
With the advances in engine technology that have occured just in the last 20 years, I find it hard to believe that Toyota couldn't make a better engine. Hell, give me a foundry, some CNC machines, a flow bench and an engine dyno, and I could make a better engine. I just couldn't turn around and make a profit at it.
Capt.Crash'n'Burn
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The new company is called Trace.
I think the exorbitant price is due to low sales volume. If they had teamed up with more investors to get their conversion certified on more aircraft types (like the Queen and King Air), then perhaps the increased sales volume would've allowed them to bring the price down to a reasonable level.
This brings up an interesting point. Has Lycoming done the same thing that International (the automotive branch that made the Scout) did??
International Scout went out of business because the Scout was so indestructible that people quit buying new Scouts. A freind of mine had one that had over 500,000 miles on it and he abused the crap out of it.
But in the case of Lycoming, since they dominate the market, people have no choice but to keep rebuilding the same engines over and over again.
Nope, it happened on the ramp right across from us in Long Beach, I used to talk with their engineers and pilots all the time. The reasons I cited were from them. They couldn't make the efficiency or reliability goals in comparison to the Lycoming 540.
The competitive disadvantage to the Orenda vs. the PT-6 is two fold. First and foremost, weight. While the turbine is thirstier and you need to load more fuel for the long legs and leave people at home, you have the option of leaving fuel at home and taking the people. With the heavier engine, you lose the option to leave the fuel at home and are always going to be payload restricted. The other is reliabilty and a high dispatch rate of the PT-6. Most turbine powered planes have a job. What that means is that the maintenance cost is nothing compared to the cost of the down time. It's not even a particularly popular installation on the Air Tractor which it is certified on. It's reliability that people pay for with a turbine, and it's worth it to them.
You seem to think that bthere is something particularly deficient about Lycoming and Continental engines when there really isn't when you consider the application of small aircraft. None of this stuff is really rocket surgery. The "needs" of small planes haven't changed, they need light weight power plants that operate efficiently in a reasonably small and continuous power band and make good power at relatively low RPM. Designing of the engines themselves hasn't changed much since these engines were designed, and when you take them apart, you see good stuff inside of them. Are they a compromise, especially with air cooling? Of course they are, but that compromise is in the name of payload and performance which are the critical components that make aviation work.
Capt.Crash'n'Burn
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I don't doubt that's the cover story they were told to tell. It stretches credulity that Toyota, with all its resources, couldn't match 50 year old technology.
It is hard to match the efficiency and reliability of those engines if operated within accepted parameters. Where they come up short is in the amount of maintenance required, lack of automation and at this point the requirement for high octane leaded fuel.
Believe whatever you want, I watched that program happen for a year. I have no qualms with automotive engines, but to think that the design advancements in them over the 50 years since the aircraft engines we use has made them better for small aircraft operations is a false premise. Would I use an auto engine in a small plane? If I couldn't get my hands on an Audi V-12 TDI, yeah, I would, but only if I was looking for more than 400 hp (and I'd still consider using an R-985). I can't build a 200hp automotive conversion that will be a better power plant than a Lycoming IO-360 in cost, weight or reliability. In an experimental application I had one that put out 235+ and completely reliable.
Dr. O
Pattern Altitude
Those who believe that the auto engine is the cheap answer to expensive aircraft engines need to go to this website:
http://www.epi-eng.com/aircraft_engine_products/aircraft_engine_products_contents.htm
And read through it CAREFULLY... The site has large amounts of information on buried pages... Click on every highlighted link on every page... Especially read the sections on piston speed... This is a company that sells auto derived engines for aircraft use, yet is right up front about the limitations and the special type of internal components (spelled 'expensive') that it takes to have reliability... Notice that the PSRU is nine grand all by itself...
denny-o (old GM engine/tranny/truck guy who spent 16 years inventing ways to make engines melt down on the dyno - in those days Olds was the toughest, Pontiac next, and Chevy a distant third)
http://www.epi-eng.com/aircraft_engine_products/aircraft_engine_products_contents.htm
And read through it CAREFULLY... The site has large amounts of information on buried pages... Click on every highlighted link on every page... Especially read the sections on piston speed... This is a company that sells auto derived engines for aircraft use, yet is right up front about the limitations and the special type of internal components (spelled 'expensive') that it takes to have reliability... Notice that the PSRU is nine grand all by itself...
denny-o (old GM engine/tranny/truck guy who spent 16 years inventing ways to make engines melt down on the dyno - in those days Olds was the toughest, Pontiac next, and Chevy a distant third)
Properly designed, massauged, sp? , tweaked, built and maintained 235+ HP out of a IO-360 is probably a reasonable output. By claiming it to be "completely reliable" is your ticket to millions.
I hereby nominate Henning to be the next CEO of Textron Lycoming. IN 50 years of development on the 0- series of aircraft engines all the Lyc engineers could not boost the power by 20% percent..You did.
Jus kiddin,, well kinda.
Ben.
Properly designed, massauged, sp? , tweaked, built and maintained 235+ HP out of a IO-360 is probably a reasonable output. By claiming it to be "completely reliable" is your ticket to millions.
I hereby nominate Henning to be the next CEO of Textron Lycoming. IN 50 years of development on the 0- series of aircraft engines all the Lyc engineers could not boost the power by 20% percent..You did.
Jus kiddin,, well kinda.
Ben.
Perhaps I should put forward my definition of completely reliable: Never left me stuck anywhere. In fact, in 2.5 years using it to commute to work, I never did any work to it but regular maint. For 235+hp I did nothing outside of a normal overhaul per Lycoming Overhaul Manual except send the cam to Ed Iskendarian for a bit of a regrind and modify the timing, some fuel system settings, minor porting and polishing work and build a proper Tri-Y pipe for it. I figure I could easily get 360hp out of it but I'd need a gear nose.
BTW, how do you figure that Lycoming never managed to boost power in 50 years of opposed engine development? They have 540cu in opposed engines all the way from 230 hp to 425hp. They recently created the and certified the O-390 and O-580 seris of engines as well.
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BTW, speaking of engine development, the "engine" part, the long block for the Windsor Ford engine as in your plane produced by Ford has been around in that same basic form for how long? Since 1962? Many of the big advancements and improvements over the years have been developed in the aftermarket sector. There just isn't much after market sector support for our aircraft engines except type certificate compliant stuff. The experimental market suppliers are typically accessory suppliers, electronic ignition and fuel control systems. You don't see water cooled cylinders being produced do you? How about beefed up or lighter weight casings? What kind of off the shelf cam selection can you go down to the Speed Shop and buy, or order online? You see Crower making cranks and rods for Lycomings & Continentals? How about pistons, what kind of selection there. Don't blame the manufacturers, blame the people who would normally supply that type of after market, Aviators.
Chill out my friend....
I have the HIGHEST respect for you, your knowledge and lifes experiences. Altho I am kinda suprised you didn't incorporate roller lifters and roller rockers during your modification process... That sir is relatively cheap HP and adds alot of longevity to any motor. My boost power comment was aimed at the 0-360 series.... Heck anyone can add cylinders to increase HP.. That was the radial motors claim to fame,, well that and those pesky oil leaks.
Peace brother...
Chill out my friend....
I have the HIGHEST respect for you, your knowledge and lifes experiences. Altho I am kinda suprised you didn't incorporate roller lifters and roller rockers during your modification process... That sir is relatively cheap HP and adds alot of longevity to any motor. My boost power comment was aimed at the 0-360 series.... Heck anyone can add cylinders to increase HP.. That was the radial motors claim to fame,, well that and those pesky oil leaks.
Peace brother...
Yeah, I am too, but I just didn't have the time to do it, and I couldn't afford to pay someone else to do it. I really would have loved to. If it would be now, I'd find a way to buy the cases and tappets from Lycoming, but I did that in the days before Lyc went to roller cams in those engines. It probably wouldn't have helped my total HP since I was where I wanted to be, but it would have most likely lowered my bsfc. Oh well, life is full of compromises. It was an engine I got on spec as payment for salvaging an Arrow and a couple other planes that got totaled in a storm off to the storage yard. I just wanted to see what I could do with one to just tweek it up a bit, I didn't even have a project to put it in at the time.