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Kitplane's article, Ly-Con's case closed.
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poneill(at)irealms.com
Guest

Posted: Sun Jan 06, 2008 7:47 pm Post subject: Kitplane's article, Ly-Con's case closed.

I haven’t decided on a primer yet.  I’m still in the process of tearing it down so that I can alodine it.  

   

Best Regards,  

Patrick #40714 / N690CT  

Do not archive  

   

       

From: owner-rv10-list-server(at)matronics.com [mailto:owner-rv10-list-server(at)matronics.com] On Behalf Of Jesse Saint

 Sent: Sunday, January 06, 2008 12:02 PM

 To: rv10-list(at)matronics.com

 Subject: Re: Kitplane's article, Ly-Con's case closed.  

  

  

   

This has turned out to be another great alternative engine war.  Anybody care to offer opinions on the best primer to use on the outside of the engine, alternative or otherwise?    

   

    

do not archive  

    

         

Jesse Saint  

    

Saint Aviation, Inc.  

    

jesse(at)saintaviation.com (jesse(at)saintaviation.com)  

    

Cell: 352-427-0285  

    

Fax: 815-377-3694  

  

  

  

       

On Jan 6, 2008, at 2:42 PM, LES KEARNEY wrote:  

  



 

     

Peter  

    

   

    

As I mntioned in my post to Kelly, I am not an engine expert / guru / authority by any stretch. Below is an exract from Ross Farnham's website: http://www.sdsefi.com/air7.html  

    

   

    

Many lay people often point out that automotive engines are not designed for continuous high output applications and will blow up when installed in an aircraft. This view is a result of complete ignorance in my opinion and is not supported by any credible facts. Modern automotive engines make use of the latest advances in computer design and modeling to optimize the design of everything from port flow, port resonance tuning, combustion chamber characteristics, vibrational node analysis and mechanical stresses. Machining and metallurgy technology is far superior to the old days when the air cooled, flat engines were developed. Technology has indeed progressed on automotive engines in the last 40 years.  

  

Automotive engines are routinely tested during development at full power and maximum rpm for periods of up to 1200 hours on a dynomometer. These engines must be able to withstand whatever stresses a customer might inflict on them such as flat out cruising on the autobahn or endurance racing, without failure. Manufacturer's limits are conservative to guarantee longevity and reliability. The engineering and capital investment that goes into a new engine release dwarfs any similar development by any piston aircraft engine manufacturer. The testing and validation methods FAR exceed those required on piston aircraft engines. In Europe, cars are routinely cruised at speeds (RPMs and load) 50-100% higher than what we see in North America with no ill effects in life span. This is real world, long term hard use.  

Just one example of the demonstrated real world reliability on the popular Subaru EJ22 engine was the 1989 record set by 3 Legacy's at an Arizona test track. These cars were run flat out for 17 days straight without failure at an average speed of over 138 mph. Similar records have been set by Saab and Chevrolet. How many people reading this article think that most aircraft engines would survive at 100% takeoff power for 400 hours? Subaru now offers the production 2.5L turbo STI rated at 300 hp, With the popularity of showroom stock endurance racing in the last decade, we get to see just how good the design and engineering is on modern cars. Thousands of Hondas, Toyotas, Oldsmobiles, Chevrolets, Mitsubishis, VWs etc. are mercilessly flogged to the rev limiter at full throttle for hundreds of hours between rebuilds. A very small fraction of these ever suffer a serious failure. Aircraft use does not put this kind of cyclic stress on an engine, being a constant load, relatively low rpm situation. Most modern car engines outlast the chassis without ever being removed. This performance can be equated into lifespans of between 4000 and 8000 hours. Even operating at 75% of maximum power and rpm limits, it is reasonable to expect a TBO of at least 1000 hours in aircraft use.    

Cheers  

    

   

    

Les

 

 ---

simon(at)sertech.com.au
Guest

Posted: Mon Jan 07, 2008 1:22 am Post subject: Kitplane's article, Ly-Con's case closed.

I have been reading  the engine debate with some interest. There are pros and cons to all  types.

  

 Just to stir the pot  a little more!!!!     have a look at this South African  development.

  

 http://www.adeptairmotive.com/site/default.asp

  

 It hasn't even flown  yet, but it is running. It has been designed from the ground up as a GA  engine.

  

 Turbocharged, 320hp at 5500 rpm, 70% 210hp at 2300 rpm, Integrated PSRU, Liquid cooled, Compatible with Avgas OR Mogas, FADEC, 130kg  (287lb).

 Targeted TBO is in  excess of 2000 hours. The engine has a fairly oversquare bore/stroke ratio (98mm  x 70mm) in order to keep piston speed low, as well as fairly short con rods Now  before anybody has a go at the revs, the average piston speed is actually lower  than conventional GA engines because of the oversquare  setup.

  

 It is a 120 degree  V6 of 3.2 litre capacity. Real smooth.

  

 Just for those with  a little experimentation in their blood. Attached is a  picture.

  

 Simon  Wilson

Adept_Engine.jpg

Description:

Filesize:

54.79 KB

Viewed:

316 Time(s)

GRANSCOTT(at)aol.com
Guest

Posted: Mon Jan 07, 2008 6:22 am Post subject: Kitplane's article, Ly-Con's case closed.

In a message dated 1/7/2008 3:24:40 AM Central Standard Time,  simon(at)sertech.com.au writes:

  	  Quote: 	
		  Just to stir the pot a little    more!!!!     have a look at this South African    development. 	
 Their  strategy is to price this experimental engine...unproven ...at Lycoming and  Continental's current prices, because they say it will weight less than current  engines.  Apparently they do not intend to have it certified.

  

 So  let me understand...they want what the current certified guys want for engines,  they want the experimental builders pay extra for a weight difference  and the experimenal operators, take all the risk; plus they are based in a  country where you can't take any legal action if this engine poops out and kills  you...sounds like a deal to me...



Start the year off right.  Easy ways to stay in shape in the new year. 

  [quote][b]

GRANSCOTT(at)aol.com
Guest

Posted: Mon Jan 07, 2008 6:33 am Post subject: Kitplane's article, Ly-Con's case closed.

In a message dated 1/6/2008 1:48:30 PM Central Standard Time,  Kearney(at)shaw.ca writes:

  	  Quote: 	
		     

Even operating at 75% of maximum power and rpm limits, it is reasonable    to expect a TBO of at least 1000 hours in aircraft use.   Cheers

    

   Les



	


 

 Les,

  

 What do you think this belief in 1000 hours is based on?   



Start the year off right.  Easy ways to stay in shape in the new year. 

  [quote][b]

johngoodman

Joined: 18 Sep 2006
Posts: 530
Location: GA

Posted: Mon Jan 07, 2008 7:52 am Post subject: Re: Kitplane's article, Ly-Con's case closed.

Aaahh,  Engines! If you want to get real exotic, try these:



The StarRotor Corp. Brayton cycle engine

http://www.starrotor.com/Engine.htm



The Beare Six Cycle engine

http://www.sixstroke.com/index.html



The infamous Axial Vector Engine Corp.

http://www.axialvectorengine.com/index.html



The Air Force HTRE-3 nuclear aircraft engine

http://members.tripod.com/airfields_freeman/ID/Airfields_ID_N.htm



My favorite is electric drag racing.

http://www.nedra.com/

These guys are actually breaking track records. They use electric fork lift motors with lots of batteries.......I think I'm going to need a larger battery tray than the one Van sent me.......

_________________
#40572 Phase One complete in 2011

apilot2(at)gmail.com
Guest

Posted: Mon Jan 07, 2008 7:50 pm Post subject: Kitplane's article, Ly-Con's case closed.

Heck you are missing the DynaCam, which IS a certified engine, that is

always going into production "next" year. Or you could totally ignore

Vans and mount up an Orenda engine that also is certified at somewhere

around 5-600hp.



On Jan 7, 2008 8:52 AM, johngoodman <johngoodman(at)earthlink.net> wrote:

 	  Quote: 	
		   



 Aaahh,  Engines! If you want to get real exotic, try these:



 The StarRotor Corp. Brayton cycle engine

 http://www.starrotor.com/Engine.htm



 The Beare Six Cycle engine

 http://www.sixstroke.com/index.html



 The infamous Axial Vector Engine Corp.

 http://www.axialvectorengine.com/index.html



 The Air Force HTRE-3 nuclear aircraft engine

 http://members.tripod.com/airfields_freeman/ID/Airfields_ID_N.htm



 My favorite is electric drag racing.

 http://www.nedra.com/

 These guys are actually breaking track records. They use electric fork lift motors with lots of batteries.......I think I'm going to need a larger battery tray than the one Van sent me....... [Wink]



 --------

 #40572 QB Wings, QB Fuse arrived

 N711JG reserved





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=156541#156541

n212pj(at)gmail.com
Guest

Posted: Tue Jan 08, 2008 10:27 am Post subject: Kitplane's article, Ly-Con's case closed.

Oh, gawd help me, but I cannot stop myself.  Here  goes.  

  

 I wrote awhile back that I'm going to stick to Ly-Con  because I didn't know enough to know what questions to ask.  Now, I know  that was a somewhat stupid statement, especially because I could find out,  given my research background, but the point was, and this verbiage below  confirms it, I have no clue when enough testing is enough, or enough failures  are too many.  I am not an aeronautical or mechanical or anything  engineer.  The one thing I cannot abide are statements that say almost  nothing, but sound like they have expertise.  "A very small fraction of  these ever suffer a serious failure."  Ok then, what's the  fraction and how does that compare to the current crop of Ly-Con's.  What's  a serious failure?  What were the outcomes?  Did the car quit  running?  Did the people slam into a concrete wall at 100 mph, because  that's what an aviator would essentially do, and whomever else was  onboard, and that's why the family scenario keeps coming up.   

  

 Putting an "experimental" engine into a four place aircraft  is fine.  As I said before I'm all for moving the bar forward.  I  don't know what engineering good or bad has gone into the certified  Ly-Cons.  I do know that the expensive certification process has kept them  from easily making these engines more "advanced."  The final testing that  goes into the auto conversions, however, is left to those who are flying  them.  It was the same way when the Ly-Cons were first being put out.   If the auto conversion folks put their designs through thousands of hours of  testing in conditions that simulate what a real plane goes through, then  fine.  Show the data. Show the process.  If they are doing so and I'm  naive in what I'm saying, fine, correct me.  But so far, the only  statements I've seen are the obfuscating statements (crap, really) that I  typically put into a report when I don't know the answer.   

  

 Why is one PSRU better than another?  Why did Jan  declare that everyone must change to the new one?  Stronger?   How?  Is the prop/PSRU combination the issue?  Was there a harmonic  issuer?  Was the metallurgy on the gears better?  Were the gears  cracking?  When you check your PSRU oil, will it tell you that there's a  hairline crack in a gear?  How will the engine hold up if you get a coolant  leak?  Will it stop working or get you to a safe landing?  How will  you know you have a coolant leak while in flight?  I am sure that all those  who are becoming Subaru test pilots for free will have asked these and thousands  of other questions and gotten very good answers.  I haven't ever seen  anyone come back with a list of these questions and the answers and posted them,  but since I'm not following the postings on these lists, maybe they have.   Hope so.  Now, this is not to say that every and all Ly-Con's  shouldn't be taken to task with the thousands of questions that an auto  conversion should be, with each question answered by test results.  We  should all be wanting to know what's the deal.  Why do Ly-Con's develop  hairline cracks in their jugs after 500 hours?  Etc.  We have a very  large number of very good engine build specialists out there with good knowledge  and experience and the willingness to share information (and Ly-Con will share  some test results).  

  

 I want Les to succeed.  I want Jan, even though I have  reservations about the person, to succeed.  I want the folks from South  Africa to build the best darn engine that has come along in a long long  time.  Just don't rely on non-critical statements.  If you deal with a  person who won't back up their claims with facts and thorough testing, walk  away, which is what I did with Jan.  And don't subject anyone else to your  test bed.  And, one more thing, make sure that when it fails, and it will,  they all will, that the manufacturer is the type that will come, take the engine  back, go over it with a fine toothed gizmo, do root cause analysis until the  cows come home, and help the NTSB determine if the fault was the engine and why,  and not just walk away and say it wasn't their fault.  You've taken it upon  yourself to be their test bed, they might as well admit to that and be part of  it contractually.  I know they won't, but to me, that is the reality of it  and that's why I'll go the route that seems to be working.  Ly-Con's with  annuals.  Annuals because I know the environment and how they are run are  going to cause problems, eventually, sometimes sooner than later, and that's why  we do annuals, not  because the technology is so old or bad that we  shouldn't have to need them.  We do them because when our engine quits, we  cannot pull off to the side of the road, we get to do what race car drivers do,  we get to plow into the barrier at speeds that do not usually  guarantee happy outcomes in a vehicle built out of aluminum, sans safety  cage.  

  

 Les, I met you once in Oregon and have followed your  comments on this list and I've always been impressed with your care and  thoroughness and intelligence.  Please help us all out as you go through  this journey and document as much as possible, especially in terms of the  questions that you have asked and the answers given.  That baby is going to  run smooth as silk when you first fire it up, I'm sure.  But I'd be doing  an annual's worth on it every 50 hours for the forseeable future, until you and  the fleet of similar installations are sure you have a winner.  Good  luck!  

  

 John Jessen

   40328.  



   From: owner-rv10-list-server(at)matronics.com  [mailto:owner-rv10-list-server(at)matronics.com] On Behalf Of LES  KEARNEY

Sent: Sunday, January 06, 2008 11:42 AM

To:  rv10-list(at)matronics.com

Subject: Re: Kitplane's article,  Ly-Con's case closed.

 

 Peter

  

 As I mntioned in my post to Kelly, I am not an engine expert / guru /  authority by any stretch. Below is an exract from Ross Farnham's website: http://www.sdsefi.com/air7.html

  

 Many lay people often point out that automotive engines are not  designed for continuous high output applications and will blow up when installed  in an aircraft. This view is a result of complete ignorance in my opinion and is  not supported by any credible facts. Modern automotive engines make use of the  latest advances in computer design and modeling to optimize the design of  everything from port flow, port resonance tuning, combustion chamber  characteristics, vibrational node analysis and mechanical stresses. Machining  and metallurgy technology is far superior to the old days when the air cooled,  flat engines were developed. Technology has indeed progressed on automotive  engines in the last 40 years.

 

Automotive engines are routinely tested during development at full power  and maximum rpm for periods of up to 1200 hours on a dynomometer. These engines  must be able to withstand whatever stresses a customer might inflict on them  such as flat out cruising on the autobahn or endurance racing, without failure.  Manufacturer's limits are conservative to guarantee longevity and reliability.  The engineering and capital investment that goes into a new engine release  dwarfs any similar development by any piston aircraft engine manufacturer. The  testing and validation methods FAR exceed those required on piston aircraft  engines. In Europe, cars are routinely cruised at speeds (RPMs and load) 50-100%  higher than what we see in North America with no ill effects in life span. This  is real world, long term hard use. 

Just one example of the demonstrated real world reliability on the  popular Subaru EJ22 engine was the 1989 record set by 3 Legacy's at an Arizona  test track. These cars were run flat out for 17 days straight without failure at  an average speed of over 138 mph. Similar records have been set by Saab and  Chevrolet. How many people reading this article think that most aircraft engines  would survive at 100% takeoff power for 400 hours? Subaru now offers the  production 2.5L turbo STI rated at 300 hp, With the popularity of showroom stock  endurance racing in the last decade, we get to see just how good the design and  engineering is on modern cars. Thousands of Hondas, Toyotas, Oldsmobiles,  Chevrolets, Mitsubishis, VWs etc. are mercilessly flogged to the rev limiter at  full throttle for hundreds of hours between rebuilds. A very small fraction of  these ever suffer a serious failure. Aircraft use does not put this kind of  cyclic stress on an engine, being a constant load, relatively low rpm situation.  Most modern car engines outlast the chassis without ever being removed. This  performance can be equated into lifespans of between 4000 and 8000 hours. Even  operating at 75% of maximum power and rpm limits, it is reasonable to expect a  TBO of at least 1000 hours in aircraft use. Cheers

  

 Les



---

n212pj(at)gmail.com
Guest

Posted: Tue Jan 08, 2008 3:55 pm Post subject: Kitplane's article, Ly-Con's case closed.

Someone pointed out to me that people might have mistaken  my use of Ly-Con.  I meant the Lycoming / Continental engine makers and not  the rebuilders.  Sorry if I didn't use this correctly.   

  

 John



   From: John Jessen [mailto:N212PJ(at)gmail.com]  

Sent: Tuesday, January 08, 2008 10:00 AM

To:  'rv10-list(at)matronics.com'

Subject: RE: Kitplane's article,  Ly-Con's case closed.

 

 Oh, gawd help me, but I cannot stop myself.  Here  goes.  

  

 I wrote awhile back that I'm going to stick to Ly-Con  because I didn't know enough to know what questions to ask.  Now, I know  that was a somewhat stupid statement, especially because I could find out,  given my research background, but the point was, and this verbiage below  confirms it, I have no clue when enough testing is enough, or enough failures  are too many.  I am not an aeronautical or mechanical or anything  engineer.  The one thing I cannot abide are statements that say almost  nothing, but sound like they have expertise.  "A very small fraction of  these ever suffer a serious failure."  Ok then, what's the  fraction and how does that compare to the current crop of Ly-Con's.  What's  a serious failure?  What were the outcomes?  Did the car quit  running?  Did the people slam into a concrete wall at 100 mph, because  that's what an aviator would essentially do, and whomever else was  onboard, and that's why the family scenario keeps coming up.   

  

 Putting an "experimental" engine into a four place aircraft  is fine.  As I said before I'm all for moving the bar forward.  I  don't know what engineering good or bad has gone into the certified  Ly-Cons.  I do know that the expensive certification process has kept them  from easily making these engines more "advanced."  The final testing that  goes into the auto conversions, however, is left to those who are flying  them.  It was the same way when the Ly-Cons were first being put out.   If the auto conversion folks put their designs through thousands of hours of  testing in conditions that simulate what a real plane goes through, then  fine.  Show the data. Show the process.  If they are doing so and I'm  naive in what I'm saying, fine, correct me.  But so far, the only  statements I've seen are the obfuscating statements (crap, really) that I  typically put into a report when I don't know the answer.   

  

 Why is one PSRU better than another?  Why did Jan  declare that everyone must change to the new one?  Stronger?   How?  Is the prop/PSRU combination the issue?  Was there a harmonic  issuer?  Was the metallurgy on the gears better?  Were the gears  cracking?  When you check your PSRU oil, will it tell you that there's a  hairline crack in a gear?  How will the engine hold up if you get a coolant  leak?  Will it stop working or get you to a safe landing?  How will  you know you have a coolant leak while in flight?  I am sure that all those  who are becoming Subaru test pilots for free will have asked these and thousands  of other questions and gotten very good answers.  I haven't ever seen  anyone come back with a list of these questions and the answers and posted them,  but since I'm not following the postings on these lists, maybe they have.   Hope so.  Now, this is not to say that every and all Ly-Con's  shouldn't be taken to task with the thousands of questions that an auto  conversion should be, with each question answered by test results.  We  should all be wanting to know what's the deal.  Why do Ly-Con's develop  hairline cracks in their jugs after 500 hours?  Etc.  We have a very  large number of very good engine build specialists out there with good knowledge  and experience and the willingness to share information (and Ly-Con will share  some test results).  

  

 I want Les to succeed.  I want Jan, even though I have  reservations about the person, to succeed.  I want the folks from South  Africa to build the best darn engine that has come along in a long long  time.  Just don't rely on non-critical statements.  If you deal with a  person who won't back up their claims with facts and thorough testing, walk  away, which is what I did with Jan.  And don't subject anyone else to your  test bed.  And, one more thing, make sure that when it fails, and it will,  they all will, that the manufacturer is the type that will come, take the engine  back, go over it with a fine toothed gizmo, do root cause analysis until the  cows come home, and help the NTSB determine if the fault was the engine and why,  and not just walk away and say it wasn't their fault.  You've taken it upon  yourself to be their test bed, they might as well admit to that and be part of  it contractually.  I know they won't, but to me, that is the reality of it  and that's why I'll go the route that seems to be working.  Ly-Con's with  annuals.  Annuals because I know the environment and how they are run are  going to cause problems, eventually, sometimes sooner than later, and that's why  we do annuals, not  because the technology is so old or bad that we  shouldn't have to need them.  We do them because when our engine quits, we  cannot pull off to the side of the road, we get to do what race car drivers do,  we get to plow into the barrier at speeds that do not usually  guarantee happy outcomes in a vehicle built out of aluminum, sans safety  cage.  

  

 Les, I met you once in Oregon and have followed your  comments on this list and I've always been impressed with your care and  thoroughness and intelligence.  Please help us all out as you go through  this journey and document as much as possible, especially in terms of the  questions that you have asked and the answers given.  That baby is going to  run smooth as silk when you first fire it up, I'm sure.  But I'd be doing  an annual's worth on it every 50 hours for the forseeable future, until you and  the fleet of similar installations are sure you have a winner.  Good  luck!  

  

 John Jessen

   40328.  



   From: owner-rv10-list-server(at)matronics.com  [mailto:owner-rv10-list-server(at)matronics.com] On Behalf Of LES  KEARNEY

Sent: Sunday, January 06, 2008 11:42 AM

To:  rv10-list(at)matronics.com

Subject: Re: Kitplane's article,  Ly-Con's case closed.

 

 Peter

  

 As I mntioned in my post to Kelly, I am not an engine expert / guru /  authority by any stretch. Below is an exract from Ross Farnham's website: http://www.sdsefi.com/air7.html

  

 Many lay people often point out that automotive engines are not  designed for continuous high output applications and will blow up when installed  in an aircraft. This view is a result of complete ignorance in my opinion and is  not supported by any credible facts. Modern automotive engines make use of the  latest advances in computer design and modeling to optimize the design of  everything from port flow, port resonance tuning, combustion chamber  characteristics, vibrational node analysis and mechanical stresses. Machining  and metallurgy technology is far superior to the old days when the air cooled,  flat engines were developed. Technology has indeed progressed on automotive  engines in the last 40 years.

 

Automotive engines are routinely tested during development at full power  and maximum rpm for periods of up to 1200 hours on a dynomometer. These engines  must be able to withstand whatever stresses a customer might inflict on them  such as flat out cruising on the autobahn or endurance racing, without failure.  Manufacturer's limits are conservative to guarantee longevity and reliability.  The engineering and capital investment that goes into a new engine release  dwarfs any similar development by any piston aircraft engine manufacturer. The  testing and validation methods FAR exceed those required on piston aircraft  engines. In Europe, cars are routinely cruised at speeds (RPMs and load) 50-100%  higher than what we see in North America with no ill effects in life span. This  is real world, long term hard use. 

Just one example of the demonstrated real world reliability on the  popular Subaru EJ22 engine was the 1989 record set by 3 Legacy's at an Arizona  test track. These cars were run flat out for 17 days straight without failure at  an average speed of over 138 mph. Similar records have been set by Saab and  Chevrolet. How many people reading this article think that most aircraft engines  would survive at 100% takeoff power for 400 hours? Subaru now offers the  production 2.5L turbo STI rated at 300 hp, With the popularity of showroom stock  endurance racing in the last decade, we get to see just how good the design and  engineering is on modern cars. Thousands of Hondas, Toyotas, Oldsmobiles,  Chevrolets, Mitsubishis, VWs etc. are mercilessly flogged to the rev limiter at  full throttle for hundreds of hours between rebuilds. A very small fraction of  these ever suffer a serious failure. Aircraft use does not put this kind of  cyclic stress on an engine, being a constant load, relatively low rpm situation.  Most modern car engines outlast the chassis without ever being removed. This  performance can be equated into lifespans of between 4000 and 8000 hours. Even  operating at 75% of maximum power and rpm limits, it is reasonable to expect a  TBO of at least 1000 hours in aircraft use. Cheers

  

 Les



---

Tim Olson

Joined: 25 Jan 2007
Posts: 2881

Posted: Tue Jan 08, 2008 4:57 pm Post subject: Kitplane's article, Ly-Con's case closed.

John,



That was one of the most well written statements I've read

in a long time on that subject.



Keep in mind that statistics give meaning when you can

determine probabilities, and overall quantities are an

important part of that.  With 100 flying Lycomings, if we

had 2 fail, we'd have 2% failure rate, right?  But, consider

that the Subaru or other conversions are currently less

than 1% of the installed base of Lycomings (in RV-10's).

That means that, down the road a while as an example,

you may know 10 people who have Lycoming failures, and

perhaps 2 who have had alternative engine failures, you

really need to look at the data pool that the numbers come

from then.  If we have 1000 lycomings, and 10 fail, that's 1%.

If we have 1/100th the number of Alternatives, (i.e. 10)

and we have 2 fail, then the failure rate is 20%.  But, to

the public, they'll hear lots more bitching on the newsgroup

from the Lycoming crowd....simply because that's where the

larger NUMBER of failures is. From the looks of it,

even once the alternatives get flying in more quantities,

they're going to be less than 5 or 10% of the total RV-10

fleet.  So, the failure rates have the possibility to

be many times larger for every failure.



Also, it's just plain not right to consider the statistical

failure rate of AUTO engines in AUTOS as the basis for

what the failure rate will be in aircraft.  You absolutely

need to be operating the engines in the airframe to

get anything meaningful to go on.



That means that today, we have very very little statistical

data on the alternatives, and even in number of hours flown,

there are many many times less hours being put on them.

So, a single failure or two is very significant.  One of

the large concerns I have is also that those with the

alternatives will tend to be tight-lipped about their

failures...which is understandable, but it just means that

nobody can determine the actual reliability.



Related to the question about PRSU reliability, and why

the new one is being *required*.....  If they had only 2 or

3 failures, think about what that means as a portion of the

total.  And then think about what that would mean if you

scaled that percentage up to the same overall quantities

as the number of lycomings flying.  2 or 3 PRSU failures

could mean 2000, or even 10,000 failures in Lycoming

quantities.  Over time, there will be a trend, but until

the same unit gets lots of time on it, we'll never know.

That's the other sad thing about the alternatives.  For

instance, the Subie being sold in 2008 is NOT the same as

the ones sold in 2007.  So, how are people to determine

the long term reliability?



Still, it's a builders prerogative to choose their engine,

and I'm glad we have the option.  The real hope is that

the alternatives can build on a design that they find

to work well, and put lots of operational time on it so

that some day it can become a larger and larger share of

the overall market.  Given some high reliabilities, I

would think that many engines could be great choices, but

for today, that choice is for those who are willing to

accept a much greater share of uncertainty.

I'm also uncertain if my engine, or my engine operational

styles are going to cause me any grief down the road, but

at least there's a pretty good pool of operational data

that we can look at to give a general feel of the outlook.



Tim	



John Jessen wrote:

[quote] Oh, gawd help me, but I cannot stop myself.  Here goes. 

  

 I wrote awhile back that I'm going to stick to Ly-Con because I didn't 

 know enough to know what questions to ask.  Now, I know that was a 

 somewhat stupid statement, especially because I could find out, given my 

 research background, but the point was, and this verbiage below confirms 

 it, I have no clue when enough testing is enough, or enough failures are 

 too many.  I am not an aeronautical or mechanical or anything engineer.  

 The one thing I cannot abide are statements that say almost nothing, but 

 sound like they have expertise.  "/A very small fraction of these ever 

 suffer a serious failure."  /Ok then, what's the fraction and how does 

 that compare to the current crop of Ly-Con's.  What's a serious 

 failure?  What were the outcomes?  Did the car quit running?  Did the 

 people slam into a concrete wall at 100 mph, because that's what an 

 aviator would essentially do, and whomever else was onboard, and that's 

 why the family scenario keeps coming up. 

  

 Putting an "experimental" engine into a four place aircraft is fine.  As 

 I said before I'm all for moving the bar forward.  I don't know what 

 engineering good or bad has gone into the certified Ly-Cons.  I do know 

 that the expensive certification process has kept them from easily 

 making these engines more "advanced."  The final testing that goes into 

 the auto conversions, however, is left to those who are flying them.  It 

 was the same way when the Ly-Cons were first being put out.  If the auto 

 conversion folks put their designs through thousands of hours of testing 

 in conditions that simulate what a real plane goes through, then fine.  

 Show the data. Show the process.  If they are doing so and I'm naive in 

 what I'm saying, fine, correct me.  But so far, the only statements I've 

 seen are the obfuscating statements (crap, really) that I typically put 

 into a report when I don't know the answer. 

  

 Why is one PSRU better than another?  Why did Jan declare that everyone 

 must change to the new one?  Stronger?  How?  Is the prop/PSRU 

 combination the issue?  Was there a harmonic issuer?  Was the metallurgy 

 on the gears better?  Were the gears cracking?  When you check your PSRU 

 oil, will it tell you that there's a hairline crack in a gear?  How will 

 the engine hold up if you get a coolant leak?  Will it stop working or 

 get you to a safe landing?  How will you know you have a coolant leak 

 while in flight?  I am sure that all those who are becoming Subaru test 

 pilots for free will have asked these and thousands of other questions 

 and gotten very good answers.  I haven't ever seen anyone come back with 

 a list of these questions and the answers and posted them, but since I'm 

 not following the postings on these lists, maybe they have.  Hope so.  

 Now, this is not to say that every and all Ly-Con's shouldn't be taken 

 to task with the thousands of questions that an auto conversion should 

 be, with each question answered by test results.  We should all be 

 wanting to know what's the deal.  Why do Ly-Con's develop hairline 

 cracks in their jugs after 500 hours?  Etc.  We have a very large number 

 of very good engine build specialists out there with good knowledge and 

 experience and the willingness to share information (and Ly-Con will 

 share some test results). 

  

 I want Les to succeed.  I want Jan, even though I have reservations 

 about the person, to succeed.  I want the folks from South Africa to 

 build the best darn engine that has come along in a long long time.  

 Just don't rely on non-critical statements.  If you deal with a person 

 who won't back up their claims with facts and thorough testing, walk 

 away, which is what I did with Jan.  And don't subject anyone else to 

 your test bed.  And, one more thing, make sure that when it fails, and 

 it will, they all will, that the manufacturer is the type that will 

 come, take the engine back, go over it with a fine toothed gizmo, do 

 root cause analysis until the cows come home, and help the NTSB 

 determine if the fault was the engine and why, and not just walk away 

 and say it wasn't their fault.  You've taken it upon yourself to be 

 their test bed, they might as well admit to that and be part of it 

 contractually.  I know they won't, but to me, that is the reality of it 

 and that's why I'll go the route that seems to be working.  Ly-Con's 

 with annuals.  Annuals because I know the environment and how they are 

 run are going to cause problems, eventually, sometimes sooner than 

 later, and that's why we do annuals, not  because the technology is so 

 old or bad that we shouldn't have to need them.  We do them because when 

 our engine quits, we cannot pull off to the side of the road, we get to 

 do what race car drivers do, we get to plow into the barrier at speeds 

 that do not usually guarantee happy outcomes in a vehicle built out of 

 aluminum, sans safety cage. 

  

 Les, I met you once in Oregon and have followed your comments on this 

 list and I've always been impressed with your care and thoroughness and 

 intelligence.  Please help us all out as you go through this journey and 

 document as much as possible, especially in terms of the questions that 

 you have asked and the answers given.  That baby is going to run smooth 

 as silk when you first fire it up, I'm sure.  But I'd be doing an 

 annual's worth on it every 50 hours for the forseeable future, until you 

 and the fleet of similar installations are sure you have a winner.  Good 

 luck! 

  

 John Jessen

   40328. 

 

 ------------------------------------------------------------------------

 *From:* owner-rv10-list-server(at)matronics.com 

 [mailto:owner-rv10-list-server(at)matronics.com] *On Behalf Of *LES KEARNEY

 *Sent:* Sunday, January 06, 2008 11:42 AM

 *To:* rv10-list(at)matronics.com

 *Subject:* Re: Kitplane's article, Ly-Con's case closed.

 

 Peter

  

 As I mntioned in my post to Kelly, I am not an engine expert / guru / 

 authority by any stretch. Below is an exract from Ross Farnham's 

 website: http://www.sdsefi.com/air7.html

 // 

 /Many lay people often point out that automotive engines are not 

 designed for continuous high output applications and will blow up when 

 installed in an aircraft. This view is a result of complete ignorance in 

 my opinion and is not supported by any credible facts. Modern automotive 

 engines make use of the latest advances in computer design and modeling 

 to optimize the design of everything from port flow, port resonance 

 tuning, combustion chamber characteristics, vibrational node analysis 

 and mechanical stresses. Machining and metallurgy technology is far 

 superior to the old days when the air cooled, flat engines were 

 developed. Technology has indeed progressed on automotive engines in the 

 last 40 years./

 

 /Automotive engines are routinely tested during development at full 

 power and maximum rpm for periods of up to 1200 hours on a dynomometer. 

 These engines must be able to withstand whatever stresses a customer 

 might inflict on them such as flat out cruising on the autobahn or 

 endurance racing, without failure. Manufacturer's limits are 

 conservative to guarantee longevity and reliability. The engineering and 

 capital investment that goes into a new engine release dwarfs any 

 similar development by any piston aircraft engine manufacturer. The 

 testing and validation methods FAR exceed those required on piston 

 aircraft engines. In Europe, cars are routinely cruised at speeds (RPMs 

 and load) 50-100% higher than what we see in North America with no ill 

 effects in life span. This is real world, long term hard use./

 

 /Just one example of the demonstrated real world reliability on the 

 popular Subaru EJ22 engine was the 1989 record set by 3 Legacy's at an 

 Arizona test track. These cars were run flat out for 17 days straight 

 without failure at an average speed of over 138 mph. Similar records 

 have been set by Saab and Chevrolet. How many people reading this 

 article think that most aircraft engines would survive at 100% takeoff 

 power for 400 hours? Subaru now offers the production 2.5L turbo STI 

 rated at 300 hp, With the popularity of showroom stock endurance racing 

 in the last decade, we get to see just how good the design and 

 engineering is on modern cars. Thousands of Hondas, Toyotas, 

 Oldsmobiles, Chevrolets, Mitsubishis, VWs etc. are mercilessly flogged 

 to the rev limiter at full throttle for hundreds of hours between 

 rebuilds. A very small fraction of these ever suffer a serious failure. 

 Aircraft use does not put this kind of cyclic stress on an engine, being 

 a constant load, relatively low rpm situation. Most modern car engines 

 outlast the chassis without ever being removed. This performance can be 

 equated into lifespans of between 4000 and 8000 hours. Even operating at 

 75% of maximum power and rpm limits, it is reasonable to expect a TBO of 

 at least 1000 hours in aircraft use./

 

 Cheers

  

 Les

 

 ---

Tim Olson

Joined: 25 Jan 2007
Posts: 2881

Posted: Tue Jan 08, 2008 7:27 pm Post subject: Kitplane's article, Ly-Con's case closed.

John,



That was a well-thought post.



Keep in mind that statistics give meaning when you can

determine probabilities, and overall quantities are an

important part of that.  With 100 flying Lycomings, if we

had 2 fail, we'd have 2% failure rate, right?  But, consider

that the Subaru or other conversions are currently less

than 1% of the installed base of Lycomings (in RV-10's).

That means that, down the road a while as an example,

you may know 10 people who have Lycoming failures, and

perhaps 2 who have had alternative engine failures, you

really need to look at the data pool that the numbers come

from then.  If we have 1000 lycomings, and 10 fail, that's 1%.

If we have 1/100th the number of Alternatives, (i.e. 10)

and we have 2 fail, then the failure rate is 20%.  But, to

the public, they'll hear lots more bitching on the newsgroup

from the Lycoming crowd....simply because that's where the

larger NUMBER of failures is. From the looks of it,

even once the alternatives get flying in more quantities,

they're going to be less than 5 or 10% of the total RV-10

fleet.  So, the failure rates have the possibility to

be many times larger for every failure.



Also, it's just plain not right to consider the statistical

failure rate of AUTO engines in AUTOS as the basis for

what the failure rate will be in aircraft.  You absolutely

need to be operating the engines in the airframe to

get anything meaningful to go on.



That means that today, we have very very little statistical

data on the alternatives, and even in number of hours flown,

there are many many times less hours being put on them.

So, a single failure or two is very significant.  One of

the large concerns I have is also that those with the

alternatives will tend to be tight-lipped about their

failures...which is understandable, but it just means that

nobody can determine the actual reliability.



Related to the question about PRSU reliability, and why

the new one is being *required*.....  If they had only 2 or

3 failures, think about what that means as a portion of the

total.  And then think about what that would mean if you

scaled that percentage up to the same overall quantities

as the number of lycomings flying.  2 or 3 PRSU failures

could mean 2000, or even 10,000 failures in Lycoming

quantities.  Over time, there will be a trend, but until

the same unit gets lots of time on it, we'll never know.

That's the other sad thing about the alternatives.  For

instance, the Subie being sold in 2008 is NOT the same as

the ones sold in 2007.  So, how are people to determine

the long term reliability?



Still, it's a builders prerogative to choose their engine,

and I'm glad we have the option.  The real hope is that

the alternatives can build on a design that they find

to work well, and put lots of operational time on it so

that some day it can become a larger and larger share of

the overall market.  Given some high reliabilities, I

would think that many engines could be great choices, but

for today, that choice is for those who are willing to

accept a much greater share of uncertainty.

I'm also uncertain if my engine, or my engine operational

styles are going to cause me any grief down the road, but

at least there's a pretty good pool of operational data

that we can look at to give a general feel of the outlook.



Tim	



John Jessen wrote:

 	  Quote: 	
		   Oh, gawd help me, but I cannot stop myself.  Here goes. 

  

 I wrote awhile back that I'm going to stick to Ly-Con because I didn't 

 know enough to know what questions to ask.  Now, I know that was a 

 somewhat stupid statement, especially because I could find out, given my 

 research background, but the point was, and this verbiage below confirms 

 it, I have no clue when enough testing is enough, or enough failures are 

 too many.  I am not an aeronautical or mechanical or anything engineer.  

 The one thing I cannot abide are statements that say almost nothing, but 

 sound like they have expertise.  "/A very small fraction of these ever 

 suffer a serious failure."  /Ok then, what's the fraction and how does 

 that compare to the current crop of Ly-Con's.  What's a serious 

 failure?  What were the outcomes?  Did the car quit running?  Did the 

 people slam into a concrete wall at 100 mph, because that's what an 

 aviator would essentially do, and whomever else was onboard, and that's 

 why the family scenario keeps coming up. 

  

 Putting an "experimental" engine into a four place aircraft is fine.  As 

 I said before I'm all for moving the bar forward.  I don't know what 

 engineering good or bad has gone into the certified Ly-Cons.  I do know 

 that the expensive certification process has kept them from easily 

 making these engines more "advanced."  The final testing that goes into 

 the auto conversions, however, is left to those who are flying them.  It 

 was the same way when the Ly-Cons were first being put out.  If the auto 

 conversion folks put their designs through thousands of hours of testing 

 in conditions that simulate what a real plane goes through, then fine.  

 Show the data. Show the process.  If they are doing so and I'm naive in 

 what I'm saying, fine, correct me.  But so far, the only statements I've 

 seen are the obfuscating statements (crap, really) that I typically put 

 into a report when I don't know the answer. 

  

 Why is one PSRU better than another?  Why did Jan declare that everyone 

 must change to the new one?  Stronger?  How?  Is the prop/PSRU 

 combination the issue?  Was there a harmonic issuer?  Was the metallurgy 

 on the gears better?  Were the gears cracking?  When you check your PSRU 

 oil, will it tell you that there's a hairline crack in a gear?  How will 

 the engine hold up if you get a coolant leak?  Will it stop working or 

 get you to a safe landing?  How will you know you have a coolant leak 

 while in flight?  I am sure that all those who are becoming Subaru test 

 pilots for free will have asked these and thousands of other questions 

 and gotten very good answers.  I haven't ever seen anyone come back with 

 a list of these questions and the answers and posted them, but since I'm 

 not following the postings on these lists, maybe they have.  Hope so.  

 Now, this is not to say that every and all Ly-Con's shouldn't be taken 

 to task with the thousands of questions that an auto conversion should 

 be, with each question answered by test results.  We should all be 

 wanting to know what's the deal.  Why do Ly-Con's develop hairline 

 cracks in their jugs after 500 hours?  Etc.  We have a very large number 

 of very good engine build specialists out there with good knowledge and 

 experience and the willingness to share information (and Ly-Con will 

 share some test results). 

  

 I want Les to succeed.  I want Jan, even though I have reservations 

 about the person, to succeed.  I want the folks from South Africa to 

 build the best darn engine that has come along in a long long time.  

 Just don't rely on non-critical statements.  If you deal with a person 

 who won't back up their claims with facts and thorough testing, walk 

 away, which is what I did with Jan.  And don't subject anyone else to 

 your test bed.  And, one more thing, make sure that when it fails, and 

 it will, they all will, that the manufacturer is the type that will 

 come, take the engine back, go over it with a fine toothed gizmo, do 

 root cause analysis until the cows come home, and help the NTSB 

 determine if the fault was the engine and why, and not just walk away 

 and say it wasn't their fault.  You've taken it upon yourself to be 

 their test bed, they might as well admit to that and be part of it 

 contractually.  I know they won't, but to me, that is the reality of it 

 and that's why I'll go the route that seems to be working.  Ly-Con's 

 with annuals.  Annuals because I know the environment and how they are 

 run are going to cause problems, eventually, sometimes sooner than 

 later, and that's why we do annuals, not  because the technology is so 

 old or bad that we shouldn't have to need them.  We do them because when 

 our engine quits, we cannot pull off to the side of the road, we get to 

 do what race car drivers do, we get to plow into the barrier at speeds 

 that do not usually guarantee happy outcomes in a vehicle built out of 

 aluminum, sans safety cage. 

  

 Les, I met you once in Oregon and have followed your comments on this 

 list and I've always been impressed with your care and thoroughness and 

 intelligence.  Please help us all out as you go through this journey and 

 document as much as possible, especially in terms of the questions that 

 you have asked and the answers given.  That baby is going to run smooth 

 as silk when you first fire it up, I'm sure.  But I'd be doing an 

 annual's worth on it every 50 hours for the forseeable future, until you 

 and the fleet of similar installations are sure you have a winner.  Good 

 luck! 

  

 John Jessen

   40328.

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