ROP versus LOP and the Lycoming IO-360

[David Brown]

I'm not sure where a target CHT method was mentioned, nor have I heard of such technique. I have heard of the target EGT value for leaning, but that's something different and something I wouldn't have a problem with. I have described 380 CHT as a maximum value, as it is possible to be running outside the red box and reach this value.

 

Mike is a pioneer in that he dissimates this information to the masses. I was learning from Mr. Busch long before I heard of APS. I understand a lot of LOP and engine management research has been done by the founders of APS, and I will be a customer of GAMI injectors when I go non-carb, but this information is too important to be kept from the masses and only taught to those with $395 and a high speed internet connection, especially when the engine manufactures say to run 50 ROP and suggest a CHT limit of 500 degrees. Notice I didn't mention Lycoming by name.

 

My thought on APS. Don't get me wrong about the people of APS, as they are aviation GIANTS in my mind. But if you're going to spend decades in this level of research, it cannot be expected to recooperate even a small amount of the investment. This is something that would be done for the betterment of the aviation community and nothing else. I have read testimonials from the students of APS and one in particular struck me as odd. I will quote it directly from the website:

 

"In ten years everyone will be operating the way these guys are teaching." --Dr. Jay Apt, Astronaut Bonanza & Twin Beach Owner

 

Why 10 years? Why not now? Because those that don't know about the teachings of Mike Busch or Deakin's (free) Pelican Perch, this information would be hidden from them. This is why I'm a Busch fan. He is extremely giving with his time and genuinly wants pilots to know how to better their engine managment skills. Because of this, Savvy Maintenance is growing by leaps and bounds. Now there's the business model.

 

Lastly, I do appologize for the harsh words, but you come in here as an "expert" flonting the APS logo. As I stated, there are more than a few on this forum that have been there, done that and have every bit of knowledge as the 2.5 day course. Notice I didn't mention Byron, Chris, Bob, Ross, Tom, ect. by name. Dang it!

 

As far as the graphic goes, it's from EAA webinars by......drum roll.......Mike Busch.

 

Thanks Darin, first of all I do come here flaunting the APS logo……not sure but I think you meant flaunting, and well, that is deliberate, Andrew Denyer and I operate and work with George John and Walter. We must perform to their standards. We work very closely on many things and some not apparent here.

 

The fact you were learning from mike Busch long before you heard about APS is a good sign for Mike publicity, and kudos to him, but that does not mean your recollection of history is accurate  .

 

As for the comments by Jay Apt, he made them a long long time ago, and he way mostly right, although many are still not on the same page even to this day. Do you know Jay? He is one of the really smart guys on this planet. He and George Braly are smart beyond most of us. What is more they are both down to earth really nice people and not at all pretentious. We are custodians of Jay Apts, Brent Blue's and Walter Atkinsons Rubber Chickens……funny story for another day, but they are great folk.

 

The APS information is not new, it was around 60 years ago, it was just lost and not as well developed. We do not keep t from the masses at all. John Deakin has published much of it on AvWeb. We all participate in many internet forums and part of the reason I am happy to be here, so long as the audience welcomes it. The fact of it is education is never free and people only value what they pay for it. The course by the way is only about 20% what you think it is. In fact we spend little time on the much believed LOP preaching, and more so we teach the science of combustion, we teach pilot inputs and the effects of chose. We teach a lot about engine monitors and correct many of the myths about them. We teach much more about failures and ability to detect them long before they cost you a fortune or cost you an accident or your life.

 

This is not a cheap nor should it be free education. It is by far the best value for money you will spend in avation.

 

APS has given away for free basically the entire course over the history of time, but it is so fragmented the only way to get the whole dose is do the course. $1AMU is not much when you understand what you get. This is why Mike recommends the course in his webinars.

 

Lastly as far as the graphic goes, save the drum roll, and in particular the bottom two graphs, perhaps you could make an attribution to the creators who actively allow reproduction only with attribution to Advanced Pilot Seminars. 

 

Cheers 

[Marauder]

David -- are you an employee of APS or receive compensation from them in any form? You preach a good message but your style leaves a lot to be desired. You lost me when you started telling us "I bet my aircraft trumps your Mooney but is that fair?". We are a community of Mooney owners, were Mooney owners, soon to be Mooney owners or want to be Mooney owners. If you are compensated by APS please disclose this (I could not read anymore of your posts, so you may already disclosed this information). And it would be appreciated if you stayed Joe Friday with us. "Just the facts sir".

[AndyFromCB]

Dave, 

 

Look at your own raw data. The difference in ICP between 50 ROP and 50 LOP is about 8% while the difference in crank angle is about 10 degrees. Whole lot to do about nothing. LOP is great for saving fuel at a cost of some airspeed and keeping your engine cleaner but no engine out there is going to self destruct at 50ROP if the CHT stay low.

[mcpilot]

I spoke with Mike Busch on a few occasions. I seem to remember him saying that barring extreme cold he leans LOP and as long as CHT is happy ICP is fine I have adopted this method I do the big mixture pull and then use mixture to control power. Starting at 75% on my EDM 830

[David Brown]

David -- are you an employee of APS or receive compensation from them in any form? You preach a good message but your style leaves a lot to be desired. You lost me when you started telling us "I bet my aircraft trumps your Mooney but is that fair?". We are a community of Mooney owners, were Mooney owners, soon to be Mooney owners or want to be Mooney owners. If you are compensated by APS please disclose this (I could not read anymore of your posts, so you may already disclosed this information). And it would be appreciated if you stayed Joe Friday with us. "Just the facts sir".

 

For a start, the comment about climb rate I think had a smile face after…..suggesting it was a tongue in cheek bit of humour. Humour translates poorly on internet forums and someone always takes offence. Hence the use of smileys. Australians tend to be a bit thicker skinned in terms of "sledging jokes", you know my plane is faster, climbs better, uses less fuel, carries more etc, so comical quips tend to be taken as terms of endearment and not attacks of a personal nature. My friends down here refer to me as the Retard Vehicle pilot. I am sure you get the gag there. 

 

On to serious maters, I really fail to see the significance of being on the payroll or not. Mike Busch is a very strong contributor and provides a wonderful resource to the Cirrus pilots and he flies a Cessna and is making a living from what he does. Does anyone slight him for it? As for APS, they have no employees at all, and unless you call Walters wife a slave….she works her butt off all week (7 days +) for no pay.

 

Myself and Andrew Denyer operate APS-Aust. and we do not operate it for profit. My wife gives up a weekend and two days of highly paid professional work to help run the course, free of charge. We have never drawn a cent and any residual funds left over are kept for funding the next seminar, and besides even if we drew a dividend the result would be sub $5/hr. To give you an example yesterday I spent 4 hours out of my working day helping a Turbo Lycoming owner with some engine handling techniques as he was a past student and asked nicely for help. That cost me and my company a significant sum. he is not the only one, I am today helping an RV10 owner in Western Australia work through engine data. We do not do this for income purposes. It probably costs us money, but the reason a course costs money is because it costs money and we do not think we should be funding everyones education to that extent.

 

As for APS-USA their theory of operation is much the same way. The small amount of net return is more like $1/hr for those guys. I dare not think the hours they have put in over the years.

 

None of the 7 of us volunteers do this for work, we all have full time careers doing other things that are our source of income, although John and Walter are now retired.

 

I hope that explain things. I will try to be a little softer on the humour if that helps 

[David Brown]

Dave, 

 

Look at your own raw data. The difference in ICP between 50 ROP and 50 LOP is about 8% while the difference in crank angle is about 10 degrees. Whole lot to do about nothing. LOP is great for saving fuel at a cost of some airspeed and keeping your engine cleaner but no engine out there is going to self destruct at 50ROP if the CHT stay low.

 

Could you please point to where our data shows only an 8% difference? That is at odds with the Dyno data I have. If you are referring to the Landmarks graph, there is no scale  on the Y axis as that graph is showing 5 different parameters with only the X axis of any concern, the rest is relationship building based on the X axis and the concept is lost when folk want to attache numbers and such to it. The latest version of the Landmarks graph is a far more accurate representation based on data collected from the Dyno in Ada.

 

The graph which some of you might have seen in the course which compares a power setting at full rich, 50 ROP and 50 LOP is this one below, and as you can see the pressure peak is approximately 33% more for 50ROP and is roughly 13 degrees closer to TDC.

 

I hope that helps.

[DS1980]

There's the problem Chris. You're not Australian so you have thin skin.

 

I have changed my graphic to be Deakin free.

[David Brown]

I spoke with Mike Busch on a few occasions. I seem to remember him saying that barring extreme cold he leans LOP and as long as CHT is happy ICP is fine I have adopted this method I do the big mixture pull and then use mixture to control power. Starting at 75% on my EDM 830

 

Sounds like you are doing things right however cogitate this for a minute. Yesterday I flew with a past student in his Piper Malibu with the Lycoming 350HP TIO540AE2A engine and it was running cool as can be. If we assumed that so long as the CHT was happy at just under 380dF and we wound in the mixture knob we would have been exceeding TIT most likely or perhaps slightly ROP of it and right in the middle of Mikes Red Fin which is the APS red box turned sideways.

Sure if you keep CHT's below 380, and most likely a bit higher, the chances of getting any detonation to ramp up are slim on a turbo and highly unlikely in a N/A unless something else is wrong. So 99% of the time what he says works.

 

The facts remain that CHT follows ICP in terms of relationship, but in terms of ideal operating limits (absolute value) they are independent of each other as Darin, myself and others have pointed out a page or two back. Mike himself has just said that to you in his statement.

 

Someone asked above for just the facts, and not to mislead the newbies, well rough rules of thumb that are like the 380dF target are just that, misleading as it works only some of the time and not all of the time.

 

The better way to think about this concept is to manage the engine so that ICP's are kept to an ideal range, then and only then if the cooling system is ideal you will be under 380dF and if not you need to do something about it.

 

By the way these ideal operating limits have a bit of fat around the edges, there is no self destruction going on anywhere near the edges of the red box. It is our opinion and George feels that we could squeeze the fat edges a bit more with long term health not affected but without lots of data that is not a call he is prepared to make. This is why these superbly designed "old technology" engines perform so well, so hard and so long. Mikes on wing lab experiment is a classic example.

 

Hope this helps too!

[Marauder]

There's the problem Chris. You're not Australian so you have thin skin.

I have changed my graphic to be Deakin free.

Well, at least he didn't bring up my sister's looks

[Cruiser]

Dave, can't see the second graph. Did it not get posted?

 

Since we are talking about the correlation of ICP to CHT could you show this relationship from 50°F ROP to 50°F LOP with actual data points? The Landmark chart (is this one the latest version?) is showing the CHT to continue increasing while the ICP remains somewhat flat before it starts to fall as it nears EGT peak. This seems contrary to what you have stated. I suspect these two parameters are not linear and do not remain constant in relationship to one another.

[DS1980]

Well, at least he didn't bring up my sister's looks

Give it time. He will. He knows everything because, well, he's taken the course.

 

I'm done being a jerk. I can't fight fire with fire this way.

[David Brown]

Dave, can't see the second graph. Did it not get posted?

 

Since we are talking about the correlation of ICP to CHT could you show this relationship from 50°F ROP to 50°F LOP with actual data points? The Landmark chart (is this one the latest version?) is showing the CHT to continue increasing while the ICP remains somewhat flat before it starts to fall as it nears EGT peak. This seems contrary to what you have stated. I suspect these two parameters are not linear and do not remain constant in relationship to one another.

 Tom,

 

My apologies, I clearly did not link the picture.

 

[Shadrach]

David,

Appreciate all the info you guys put out (conceptual graphs included). However, a large percentage of us are flying behind 4cyl Lycs with 8.7:1CR timed at 25BTDC. So as good as this info is, it only applies to many of us so far as it illustrates the relationship between a number of parameters.

Have you guys ever published or released any data that applies to these engines? While highly respected, APS (in the states at least) is perceived more as a Continental centric institution and most of the stuff on the web seems to reinforce that perception.

Has any one at APS ever considered doing an engine series specific course?

I agree that the fuzzy red box is narrower than the conventional 100ROP-50LOP >65%hp. I know this from my own testing in spring and summer time at low altitudes. In warm weather I use 340 as CHT max in level flight. I rarely need more than 25LOP to stay under 340df even at high power settings down low in warm weather. No way, No how my engine is close to the "red box" with a CHT of <340df when the OAT is in the high 70s. As I've learned more, I've become slightly less conservative.

[mcpilot]

Hey David,

 

You bring up a few really good points here.. Are engines are different, and it would be interesting to see info pertaining to the Lycoming IO360 series.  HAs anyone "experimented" with different timings?

[jetdriven]

On the LOP side, a dual mag Io360A3B6D is quite a performer at 25 degrees, and loses power at 20. It's quite noticeable, a 3-5 knit reduction in cruise speed and a lower rate of climb. Note it's only certified for 25 degrees. The two-mag A3B6 roller engine makes more power LOP at 25 degrees than 20, but it runs warmer at that timing. ROP 20 degrees and 25 are closer than on the D engine. 23 is a good compromise between LOP performance and CHT.

[carusoam]

Whether David is paid or not...

What is important is, does he represent APS? Does APS stand behind what he says?

Or is it another opinion, that I need to sort through to understand? Does this information directly or indirectly apply to me, my AC or my community?

We have a thread that is an introduction of all players. I recommend finding it and adding to it.

Anyone remember the thread title?

Best regards,

-a-

The title of the thread is..... Introduce Yourself

[David Brown]

David,

Appreciate all the info you guys put out (conceptual graphs included). However, a large percentage of us are flying behind 4cyl Lycs with 8.7:1CR timed at 25BTDC. So as good as this info is, it only applies to many of us so far as it illustrates the relationship between a number of parameters.

Have you guys ever published or released any data that applies to these engines? While highly respected, APS (in the states at least) is perceived more as a Continental centric institution and most of the stuff on the web seems to reinforce that perception.

Has any one at APS ever considered doing an engine series specific course?

I agree that the fuzzy red box is narrower than the conventional 100ROP-50LOP >65%hp. I know this from my own testing in spring and summer time at low altitudes. In warm weather I use 340 as CHT max in level flight. I rarely need more than 25LOP to stay under 340df even at high power settings down low in warm weather. No way, No how my engine is close to the "red box" with a CHT of <340df when the OAT is in the high 70s. As I've learned more, I've become slightly less conservative.

 

Guys, I will try to uphold the high standards of APS data backed fact.

 

Feel free to question me….if need be I can double check with John Walter or George, as barely a day goes by where I do not communicate with them. But it needs to be a really good reason to do so.

 

On any threads like oxygen use or other non engine management matters they will most likely be my opinion only…….so treat it as such. but wherever I can on engine related stuff I will attempt to bring you APS derived data backed material.

 

That is no unreasonable I hope.

[David Brown]

 

 

However, a large percentage of us are flying behind 4cyl Lycs with 8.7:1CR timed at 25BTDC.

 

That is the majority of all airplane owners so do not srtress. The fuel does not know the difference between aircraft. The data and theory of operation does not change whether it is a IO520, IO540, IO360(LYC) or for that matter IO360(TCM) so there is nothing in the APS teaching that matters from one type to another. Let us think like TCM,LYC, P&W, CW, Briggs & Stratten, Harley or Honda…….

 

The principals are the same.

 

 

 

 

As I've learned more, I've become slightly less conservative.

That there is the beauty of education. Need I say more.

[Shadrach]

The principals and concepts are the same, but the engines are somewhat different. it sure would be interesting to view data from one's own engine series in the class.

[David Brown]

Ross,

 

I am not sure what you mean, there is certainly differences in engines, but there is no difference in the science of combustion. Your earlier posts stated about the core being TCM focussed, but the funny thing is the Dyno runs and a lot of the data collected came off a Lycoming many years ago.

 

The class has some in flight video, turbo and N/A. We even just this year added a small section explaining briefly the conceptual difference between the TCM and LYC fuel systems and a carburettor.

 

So I am not sure what your concern is.

 

The vast majority of folk who have never taken the course have all manner of preconceived ideas and I am yet to have anyone explain precisely what the class is about, most think it is 2.5 days on how to run LOP. Oddly enough that is not it at all and is only a small part overall.

 

Once you are skilled up with the understanding, you can take this and apply it to any engine you fly behind.

 

Once you have done the course, you will understand what I mean. You could book in for the next one in Australia…I will make an extra effort to cover your questions….Its a long flight though 

[carusoam]

David,

The topics that you cover fit to all engine manufacturers, for all engines, N/A or TC or TN'd....

What I would like to come away with is the data that specifically covers my plane and power plant.

For me, the ability to interpretate various graphs gets lost over time.

I have two variations of flight...(typical of Mooney pilots)

(1) all out fast.

(2) efficient flight. Speed is the priority, but minimizing fuel waste is next most important.

(3) all phases of flight, from start, taxi to take-off, climb, cruise and descent.

Would it be possible for APS to set a Mooney centered presentation?

I would rather sit through extra presentations of Mooney engines ie...Cont., Lyc., N/A and TC'd, than sit through similar presentations about Continental IO550s mounted to Orca shaped plastic planes or brands B and C.

If the sole focus was Mooneys with N/A continental engines, how long would the course take? 1/2 day?

I am interested in learning the finest details about the IO550(n) with a Hartzell TopProp and hearing questions about various Mooney operations by various Mooney owners.

What's your thoughts?

Are you able to answer for APS/USA?

Best regards,

-a-

[David Brown]

David,

The topics that you cover fit to all engine manufacturers, for all engines, N/A or TC or TN'd....

What I would like to come away with is the data that specifically covers my plane and power plant.

For me, the ability to interpretate various graphs gets lost over time.

I have two variations of flight...(typical of Mooney pilots)

(1) all out fast.

(2) efficient flight. Speed is the priority, but minimizing fuel waste is next most important.

(3) all phases of flight, from start, taxi to take-off, climb, cruise and descent.

Would it be possible for APS to set a Mooney centered presentation?

I would rather sit through extra presentations of Mooney engines ie...Cont., Lyc., N/A and TC'd, than sit through similar presentations about Continental IO550s mounted to Orca shaped plastic planes or brands B and C.

If the sole focus was Mooneys with N/A continental engines, how long would the course take? 1/2 day?

I am interested in learning the finest details about the IO550(n) with a Hartzell TopProp and hearing questions about various Mooney operations by various Mooney owners.

What's your thoughts?

Are you able to answer for APS/USA?

Best regards,

-a-

 

Happy New Year -a-

 

How about I work backwards through your questions.

 

Am I able to answer on behalf of APS-USA, well I guess the technically correct answer is No, however I am reasonably confident that if you email John Deakin via the website link you will get a similar reply.

 

What it seems you are asking for is the course to be run just for you and your plane, and it would still take a good two days, would be a bit quicker because of the less questions that get asked but less learning from those questions, so I would say that is a downside.

 

Contrary to the popular myths, the course is not what you think it is. Just like it is not all about running LOP. It is not focussed on any one breed, in fact the engine video's in the dyno test cell are a Turbocharged Lycoming engine. The course is generic, because the laws of physics apply equally to all men/women/planes……with the obvious exception to Mooneys  . The couple of video's done in the air use a T34 and a V35B and no Cirrus involved. That is not true at the moment on the test cell as it has a TN IO550 from an SR22 on it, but it matters not.

 

One thing we focus on in the course is not to teach a "cookbook" approach to things, and it feels like that is what you are asking for. The better outcome is to actually teach you how to be a good pilot in terms of the course content, how to understand the combustion event, how to understand and not just look at your engine monitor and how to use all the learning you do in a practical manner.

 

Then…..you get to jump in your plane, be it a Mooney, Beech, Cirrus, Cessna, or RV   , and start applying your new found "Knowledge and Understanding" to suit your various needs.

 

The outcome you are asking I think is actually what you will get, but you get that by doing a bit of self learning with the power of the education. There is plenty of time during breaks and over dinner to discuss any finer points you wish to ask.

 

I can tell you are an accountant….you can't count    You know that joke I gather?

 

 

I have two variations of flight...(typical of Mooney pilots)

(1) all out fast.

(2) efficient flight. Speed is the priority, but minimizing fuel waste is next most important.

(3) all phases of flight, from start, taxi to take-off, climb, cruise and descent.

Yes all that and more is covered and the laws of physics will apply the same. No exceptions.

 

Book in with Deakin for the March course, if you are able to do that tell him I said to give you the online course now to get started with, and it is available for refresher reviews for up to 12 months. So bits you miss, forget or just not sure of you can go back and replay time and time again. If you turn up and say I learned nothing and the course sucked I want my money back……he will write you a cheque on the spot. He might faint with shock as nobody as ever done that in 13 years and thousands of students. But the guarantee exists!

 

Heck, I might be there around the same time so I might even see you there, they might even get me on the job and working! 

 

Email JD here http://www.advancedpilot.com/contact.html

Register here http://www.advancedpilot.com/livecourse.html and click on the signup tab.

 

Hope that helps.

[carusoam]

Pm sent...

[John Pleisse]

Seriously, does anyone still have misgivings about LOP operations? That's so 2008. 

 

The survey says...34% ROP or over half of the total of LOP respondents....(top of the page). The date on this thread is 2013.

[DaV8or]

Good grief. This ol' thing again? My plane runs crappy LOP most days and chasing the illusive ideal GAMI spread and smooth ops deep into LOP is both very time consuming and can be pretty expensive. Fun hobby for the tinkerers, but I fly for fun so...

 

I run 65% at around peak most days. If I want to get somewhere faster I'll go 65%-75% 125 deg ROP. This means I do not run WOT and 2700 rpm. I have no issues what so ever with CHTs no matter what I do. Works well enough for now and I get the same 7.5 to 8.5 gph fuel burn everybody else gets, or I'll go up to the 10 if I want to faster.