Viking Aircraft Engines, thoughts? (Honda piston AE?)

Discussion in 'Hangar Talk' started by exncsurfer, May 26, 2017.

  1. exncsurfer

    exncsurfer Pattern Altitude

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    I am not a builder or a flyer of experimentals. On the surface, this seems like a good idea, using a mass produced engine in small aircraft. Viking Aircraft Engines is taking Honda engines and converting them for aircraft use. Why isn't this done on a larger scale, and for certified engines? Is it even possible for a 3rd party to get a certified conversion product? I'm sure Honda could do it but they would have no motivation as the market is tiny from their perspective. It seems that this could significantly lower the price of piston singles, no?

    Discuss...

    Edit: I forgot to post the link: http://www.vikingaircraftengines.com/
     
  2. citizen5000

    citizen5000 Ejection Handle Pulled

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    If the idea was solid then Viking would be outselling Lycoming and Continental. Or at least be outselling Rotax. But they are not.
     
  3. Sac Arrow

    Sac Arrow Touchdown! Greaser!

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    The merits of using automotive engines for aircraft engines have been discussed extensively in other threads. If you drove your Accord flat out full throttle for five hours at a time, you will see issues develop with your engine that you wouldn't see in a more normal duty cycle.

    A brand new gasoline engine designed ground up for aviation would probably resemble what we have now in form factor, although perhaps with solid state ignition and EFI. From a BMEP perspective, standard Lycoming and Continental AC engines, particularly in the larger sizes, are actually fairly efficient when compared to modern automotive engines.
     
  4. Lachlan

    Lachlan En-Route

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    Converting airplane engines for automobile use is far cooler, man.
     
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  5. GRG55

    GRG55 Final Approach

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    :yeahthat:

    If it really was a good idea, it would already have happened on a larger scale.

    Even most of the "exotic" experimental manufacturers, such as Lancair with its piston version of the Evolution, use purpose built aircraft engines, not converted automobile blocks.
     
  6. RJM62

    RJM62 Touchdown! Greaser!

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    The challenge to getting a powerplant approved for use on a certificated aircraft is a bureaucratic one, not an engineering one.

    Rich
     
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  7. dell30rb

    dell30rb Final Approach PoA Supporter

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    I'm not sure how valid the argument about running the automotive engine full throttle for 5hrs at a time is. Yes maybe for the little accord engine. Automotive engines are routinely marinized for use in boats which see a similar profile to aircraft. They cruise about 75% power too. Engines can last 20 years and 3-4,000 hours or more if they aren't killed by improper maintenance (usually are).

    Also any engine designed for a truck is going to be just fine running at 75% power all day long. My F150 ecoboost actually makes all of its 420ft-lbs of torque at 2000 rpm. On a flat highway I am probably pulling down 70% power easy when towing my boat on cruise control in 6th gear at 2000 RPM.
     
  8. coloradobluesky

    coloradobluesky En-Route Gone West

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    There are several pretty good reasons why car engines dont make good airplane engines. Airplane engines are built light as can be because light weight in an aircraft is more important than in a car. Airplane propellers can't break the sound barrier, which happens around 2900 rpm. So aircraft engines are built with 2900 as their redline and max power rpm. Air cooling is simpler and lighter and works better in aircraft (because they go faster and have more air flow). Aircraft engines have several features that maximize reliability in the event of sub system failures. Dual ignition, carb on the bottom (fire), no liquid cooling system failures to worry about, engine runs in event of electrical system failure etc.

    Experimental builders have worked around these problems and made Subaru engines and other car engines work in an airplane. But the solutions weren't really very good. The plane flew, but it was overweight and not as reliable etc. Just not as good as with a made for airplanes engine.....

    The reason car engines cost less than aircraft engines, is they make 100's of thousands of them. If Lycoming could sell 100,000 0-360s a year, they would cost a LOT less, like less than half. Its called ECONOMY OF SCALE!
     
  9. GRG55

    GRG55 Final Approach

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    All of which translates into mucho $$$.
     
  10. exncsurfer

    exncsurfer Pattern Altitude

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    Yea, the scale is the main problem here. When you're selling 10 and 20 counts of airplanes per year per manufacturer, where is the motivation to develop anything new. Probably wouldn't even be worth it to Honda to give 2 guys a shed in the parking lot of one of their factories.

    The Viking Honda weighs 220 lbs and makes 130HP and 600 lbs of thrust, according to them. I'm not sure how that compares to your common certified light weight purpose built Aircraft engines though.
     
  11. coloradobluesky

    coloradobluesky En-Route Gone West

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    If it makes that 130 hp above 2900 rpm its going to need to be a geared engine which is a bad forward weight, and if it is liquid cooled, its going to need a heavy radiator etc. And the associated risk if those items fail.

    I looked the website and the Viking engine appears to be water cooled, geared and turbo. Not exactly cheap or simple. Honda makes good reliable stuff though.

    Another item is, getting mechanics to work on such a uncommon engine. That and getting parts. Getting it rebuilt. Resale value. Good luck....

    You can probably find one at Oshkosh. It belongs in an experimental.
     
    Last edited: May 26, 2017
  12. citizen5000

    citizen5000 Ejection Handle Pulled

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    The weight, HP and thrust numbers have no meaning if the engine has a limited life trying to deal with the real issue for aviation engines. Operating at extremes of temperature and air pressure differentials in short periods of time. The proof is in the sales again. None of these engines are showing up in the air in any quantity or for long.
     
  13. Ted DuPuis

    Ted DuPuis Administrator Management Council Member

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    That is incorrect:

    http://www.evolutionaircraft.com/

    The Evolution is available with a PT-6 or a Lycoming TEO-540 (electronically controlled). I flew the Lycoming variant a number of years ago.
     
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  14. James331

    James331 Touchdown! Greaser!

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    I do recall a guy who used to post here with a most impressive zenith.

    Of course it didn't have a little civic engine in it
     
  15. Ted DuPuis

    Ted DuPuis Administrator Management Council Member

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    #bandozer
    The story is more complex than that. Lancair as a company got to the point where the Evolution was the only plane they were building or selling kits for (and since part of the purchase was the builder assist program. They weren't as interested in supporting the previous generations for many reasons, hence the spin-off to Texas. It even says right on the lancair.com website that the new company was created (Lancair International, LLC).

    http://lancair.com/about/

    "Evolution Aircraft" is really what was Lancair, although granted it is a separate legal entity. This was part of the restructuring Kevin Eldredge did when he joined Lancair, and also focused on getting the piston variant better recognition since, prior to that, Lancair wasn't pushing it. For a while, Lancair didn't even advertise the piston Evolution other than to say in one sentence (buried within other parts of the webpage) that it was available. However, it was always there and does offer some advantages vs. the turbine depending on your mission.

    I'm guessing you didn't go to www.evolutionaircraft.com since there's a picture of the piston version right on the homepage (being the turbine version), and it discusses the piston variant. I can assure you there is a piston variant since, as I said, I flew it.

    Saying "there is no Lancair Evolution" is at best an uneducated half truth.
     
  16. Goofy

    Goofy Line Up and Wait

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    Insight into Viking:

    Readers of this site inform me that Jan Eggenfellner's new enterprise, Viking Aircraft Engines, is the exact same thing as with the Subaru engines, all over again with Honda Fit engines. They say it's same old Jan, same old business model, same old customer and vendor relationship problems, same old censoring, same old petty vindictiveness, same old use of customers as R&D Dept, same old robbing Customer Peter to pay Customer Paul, same old late shipping, same old shipping of incomplete engines, including NO ECU, same old dodging questions about how much the engine weighs or how much power it produces or where the engines come from or how TBO is determined, same old PSRU issues, same old personal attacks on anyone who doesn't drink the Viking Kool-Aid. They say Jan even reads and deletes Private Messages on his current site.

    All the censoring on Eggenfellner's own Viking Yahoo Group led to a user, who couldn't get his questions answered on Jan's group, creating a new uncensored Viking Aircraft Owners group. That group was immediately threatened, including late night phone calls to the owner's home, out of existence by Eggenfellner.

    A new group, with undisclosed owner, was then created. Check it out HERE to learn the truth about how nothing has changed for Eggenfellner and how he does business. Some of the Eggenfellner antics are downright funny - for example, Jan has been caught multiple times using aliases in the uncensored group, to try to inject some positive Viking spin into the conversation. Anyone who joined the new uncensored group was immediately banned from Jan's Viking group. I really think he's losing it mentally now; numerous others have also made that observation.
     
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  17. Tantalum

    Tantalum En-Route

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    Those new Raptor aircraft that came up in another thread are using an Audi diesel
     
  18. ircphoenix

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    O-320s are approx 280. 360s are about 300. So heavier. Don't know about the Viking engine, but if it's water cooled vs air cooled, there's significant weight there that could be messing up the program. Then there's the issue of gearing. If they have to rig up a gear box to turn 4000 RPM into 2600 RPM, that's additional weight.
     
  19. ircphoenix

    ircphoenix En-Route

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    Highlights... Liquid cooled, turbocharged, lots of talk about peak HP in the 5,450 RPM range. Which means all of the things in my previous post are problematic in terms of weight.

    Also... I missed the second page of posts on my phone, so I apologize if I repeated something someone else said.
     
  20. citizen5000

    citizen5000 Ejection Handle Pulled

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    The Raptor is a vapor plane. No one has seen or sat in one since it does not exist.
     
  21. Art VanDelay

    Art VanDelay Pattern Altitude

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    Dang Teddy - I'm jealous ! That piston version with some FIKI would be my go to dream ship if I ever tripped over a million bucks. Reason being - I could afford to put gas in it and with the repairmans certificate in my pocket I could afford the maintenance. The BRS part is a plus as well.
     
  22. Ted DuPuis

    Ted DuPuis Administrator Management Council Member

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    I really enjoyed it. A very capable and fun to fly plane, without the Lear 23 stall characteristics the IV has. Plus a really long range.

    If you ever trip over a million bucks and buy one, send me a PM. I'll give you some thoughts on what I'd change engine wise.
     
  23. Tantalum

    Tantalum En-Route

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    For sure, and they've been "15 months away" from a flying example for eons.. but just using them as an example that the "use car engine in plane" is not just a POA pseudo-engineer fantasy
     
  24. Tantalum

    Tantalum En-Route

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    The thought of car engines in planes is tantalizing because they're relatively cheap, "modern", and some of them have impressive hp/torque figures for their size and they have perceived reliability. The biggest limitations I see are the reliability and complex failure modes and the grueling environment of operating at near max power for long periods of time in temp and pressure extremes.

    Gearing has been done, not just by Rotax but by Continental and used in Cessna twins. Even liquid cooling exists and goes back to WW2 days.. the Extra 400 had a liquid cooled engine, it was a sales failure in part because people didn't trust its powerplant, but I'm not sure the fleet (small as it is) had engine reliability issues in practice

    Granted, if I was going to be building certified planes I would stick to tried and true air cooled Co/Lyco. You'd be better off just going with a turbine before investing all the time and money to build "a better" piston engine
     
  25. Art VanDelay

    Art VanDelay Pattern Altitude

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    Heck I'd even take out the seats and do some critter runs for you.
     
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  26. SoonerAviator

    SoonerAviator En-Route PoA Supporter

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    Diesel engines are much better-suited for replacing the Lyco/Conti power plants. Can run on cheaper Jet fuel, tons of torque at low rpm, turbocharged to eliminate loss of power at altitude, and simple as can be. The problem has always been the high weight of automotive/agricultural Diesel engines. If I was looking at designing a replacement engine, it would be something akin to a diesel compression ignition engine.


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  27. citizen5000

    citizen5000 Ejection Handle Pulled

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    You were good bringing it up as an example. I just wanted to remind others that so far the Raptor guys are running a scam. Even the ICON is more aeroplane than the vapor Raptor.
     
  28. weilke

    weilke Touchdown! Greaser! PoA Supporter

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    I don't think a purpose built aircraft engine designed today would look anything like a Lycoming or Conti. More like a Rotax or modern motorcycle engine.
     
  29. Capt. Geoffrey Thorpe

    Capt. Geoffrey Thorpe Touchdown! Greaser! PoA Supporter

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    I'm surprised to hear that considering that my aircraft engine runs at 5600 rpm all day long. Or, at least until I run out of fuel.
     
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  30. GRG55

    GRG55 Final Approach

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    If reciprocating diesels are such a near perfect solution why have they not made greater inroads?

    The European automakers have produced a number of lighter weight, high output Diesel engines, so the one detracting feature you mention, weight, can be satisfactorily addressed.

    The change to a different type of fuel from avgas isn't an impediment since jet fuel is readily available at airports everywhere.

    I can remember seeing experimental diesels at Oshkosh more than 25 years ago. Yet even in that segment, which tends to pioneer and embrace leading edge ideas, reciprocating Diesel engines are all but absent from flying airplanes.

    Cessna's fling with them was short lived. Leaving Diamond as the one notable user example, but it also only produces a very limited number of it's airplanes with Diesel engines.

    All this suggests to me they aren't as perfect or as simple a solution as we might wish. I wonder why?
     
    Last edited: May 27, 2017
  31. Tantalum

    Tantalum En-Route

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    This has perplexed me too. My dad sang the praises of diesels all throughout my growing up years.. he's an engineer (mechanical, thermodynamic) and there's a reason they're used in boats and trucks. The pro's I see of diesels are:

    *no electrical needed at all
    *can tolerate abusive environment and running at or near full power for long and sustained periods of time
    *diesel fuel is much "safer" to work with (much higher flash point, etc.)
    *no threat of carb ice
    *the higher temps and pressures make for a more thermodynamically efficient combustion cycle
    *great low end torque
    *can handle a ton of abuse

    The cons, for our sport, are
    *weight
    *weight
    *weight
    *the diesels I have worked with at least never rann as "smooth" as gasoline engines. Even the brand new Yanmars in the launch boats and the fancy Volvo Penta diesels on multi-million dollar sail yachts were rough. So there would be some vibration issues to overcome with the prop, etc. But Diamond found a way to get over that so clearly it's not impossible and luxury car makers use them too... so it can be done

    I think the real answer to that question is much more complicated, and possibly philosophical. And I've always had a hard time buying the argument "if it was such a good idea someone would have done it by now" <- if that logic were true we would never have new inventions. So *why* has it not caught on? I honestly think it all comes down to familiarity and performance ROI

    There is a huge familiarity with Lyco and Co with pilots, owners, and mechanics. Our hobby is so expensive as it is that very few people have the financial fortitude to risk being the guinea pigs on a new piece of tech. And, even if money is no object pilots realize their sport has some risks associated with it. Would you rather trust a brand new piece of technology powering your plane, or something that has been around for decades (most people will pick that which has worked for decades). Glass has caught on now, but a lot of people still prefer 6 pack and I remember reading threads back in the early 2000s where people had issues trusting it ("what about total electrical failure, lightning strike, etc. etc."). And frankly I think 90% of the reason glass is common in the GA world is because it looks cool (let's be honest).

    I also think that the lack of a real performance advantage means you don't really need to change the wheel. If you really need a performance gain you'll step up to a turbine... otherwise with the options out there right now there is really not some area where a diesel will bring you better speeds or higher useful loads. I think that's the same reason retracts are going out of favor in GA. Sure you may get a couple knots more airspeed (and there's a cool factor to it) but for most people that speed advantage "isn't worth it" until you're up in the 250 knot plus realm. Just look at Diamond's stats for their diesels... you really don't get much for having a diesel engine other than "cool I can burn Jet A" and then you have the looming fear or "what if something breaks, will my mechanic be able to fix it?"

    My $0.02 (or whatever's it's worth)
     
  32. Direct C51

    Direct C51 Pre-takeoff checklist

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    I just want to correct these misleading statements. The RPM is only half of the equation. The propeller (tips) breaking the sound barrier is a function of RPM and prop length. Mark Langford routinely flew his KR2 at 4000 RPM. Formula 1 planes are also around 4000 RPM. I'll be flying my 54" prop at up to at least 3400 RPM without even going transonic.

    The second half of that statement is also wrong. Max power is not at 2900 RPM in a LyCon period. Maybe in a specific airplane with a specific prop, 2900 RPM will be max power available. Put that same engine in a different airplane with a different prop and max power output might be at a different RPM.
     
  33. SoonerAviator

    SoonerAviator En-Route PoA Supporter

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    I'm sure the challenge of cutting weight in a diesel is quite the difficult task. They run at much higher internal pressures, which necessitates stronger (usually heavier) components than the gasser counterparts.

    Second, is the fact that there's almost no payback in trying to get a new diesel powerplant certified as a replacement for existing airframes. The demand just isn't there for anyone who has 100LL available.

    So, that leaves you with trying to build/design a compression ignition engine for use in an aircraft that hasn't been certified yet. Pretty small market reduced to an even smaller market.

    Final answer: despite the obvious challenges in shedding enough weight, the lack of demand for new piston singles pretty much explains why so few are even interested in making an attempt.


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  34. Sundancer

    Sundancer En-Route

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    I'm no engineer or gear head, but it seems auto engines are built to tight tolerances, and to run in a narrow, well controlled temperture range, managed with liquid cooling. So, a good deal of power and fuel efficiency, turning higher-than-propellor rpm. . .

    Airplane engines aren't so much air cooled as they are oil-and-fuel cooled, and so have slacker tolerances, and lower compression, because temps are harder to manage. And, for the lower end engines, lower rpm, that match well with propellor rpm sweet spots.

    Sticking a auto engine in an airplane means adding the liquid cooling plumbing, and probably some kind of reduction drive or gearing for the prop, maybe dealing with ignition issues, and/or adding dual ignition, etc.
     
  35. azblackbird

    azblackbird Cleared for Takeoff

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    Tons of V-8 powered aircraft around that make the rounds at the various airshows and fly-ins. Like this one... you have to admit, this sounds almost as good as the real one. ;)

     
  36. asicer

    asicer En-Route

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    Um, disagree. Vehemently.;)
     
  37. azblackbird

    azblackbird Cleared for Takeoff

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    No doubt there is no better sound than an Allison or Merlin cruising past you at 400mph. :cool:
     
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  38. kyleb

    kyleb En-Route PoA Supporter

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    An engine is an engine. You have to select an engine with an appropriate duty cycle for the intended role. Adding liquid cooling has many benefits - better efficiency being one of those. The downside is the complexity and inherent risk of the cooling system.

    As far as Viking goes, an acquaintance of mine put the first Viking into an RV-12. Being the roll-out customer, he spent a lot of time working with Jan Eggenfellner to put together the installation package for the RV-12. There was a lot of iterative work on the installation, but ultimately, I think he is satisfied with the product. He's been flying the airplane for years. The one thing he has never done is give out any weight or performance information. My sense is that his airplane is somewhat heavier and somewhat underperforms stock Rotax RV-12's.

    Eggenfellner's business practices are what they are. A small shop can't provide the long term service or service infrastructure that Lycoming, Continental, or Rotax can. That's a fact. If you go into an alternate engine expecting great documentation and an always available customer support, you'll be disappointed. If you expect a bolt-on, proven installation like you'd get with a Lycoming (for instance), you'll be disappointed - you're on the development side of experimental aviation.
     
  39. Ted DuPuis

    Ted DuPuis Administrator Management Council Member

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    You're severely discounting the importance of the air in the equation here. You can easily see 50-100F differences in CHTs between good baffles and bad baffles on the exact same airframe. BTDT many times.

    Mixture setting and oil cooling matter as well, but air is by far the most important factor in the equation.
     
  40. coloradobluesky

    coloradobluesky En-Route Gone West

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    Ultimately ALL engines are air cooled. What else is there? They may have water or oil intermediary, but in the end, they rely on the air to cool them.

    And dont forget, water cooled engines have to have water jackets. So their engine blocks are heavier.
     
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