Question regarding TIT

[carusoam]

I also notice we are getting closer...

But, when some MSers share their data... when we click on their graph, we can get the data at that point in time....

i was looking for specific tit numbers, but only got the graph... and visual interpolation on a computer is so 90s... 

Look for Sort of a more live link...

That way we can generate a graph of just TIT, or EGTs, or FF vs....

When it comes to sharing Savvy data... Paul is our most Savvy key guy... 

Best regards,

-a-

[kortopates]

I also notice we are getting closer...
But, when some MSers share their data... when we click on their graph, we can get the data at that point in time....
i was looking for specific tit numbers, but only got the graph... and visual interpolation on a computer is so 90s... 
Look for Sort of a more live link...
That way we can generate a graph of just TIT, or EGTs, or FF vs....
When it comes to sharing Savvy data... Paul is our most Savvy key guy... 
Best regards,
-a-

Ah, good point Anthony, I didn't comment on that because it's superfluous to me since I had his N number
But Scott, @231lv, you can post a link to one flight or all flights. I suggest the former, then anyone on Mooneyspace can play with your data using our Savvy tools. It's really not practical any other way.

Just go down to the bottom of the page and click where you see Sharing options to generate a link to share with. Savvy has awesome tools!


Sent from my iPhone using Tapatalk

[231LV]

Outstanding data and information, Paul! Thank you....Now I have a sense of what I am trying to accomplish

[231LV]

1 hour ago, kortopates said:

Ah, good point Anthony, I didn't comment on that because it's superfluous to me since I had his N number
But Scott, @231lv, you can post a link to one flight or all flights. I suggest the former, then anyone on Mooneyspace can play with your data using our Savvy tools. It's really not practical any other way.

Just go down to the bottom of the page and click where you see Sharing options to generate a link to share with. Savvy has awesome tools!


Sent from my iPhone using Tapatalk

here is the link with every flight since install of the EDM 900

https://savvyanalysis.com/my-flights/1006534/e12e2b6c-01aa-4ac4-88dd-f95550255263

[Bryan]

On 4/16/2019 at 1:07 AM, johncuyle said:

Couple notes:  The HP% on engine monitors is generally not too useful.  I don't know about the 900, but I think on mine it's calculated using MP and RPM. 

I disagree.  My %HP is something I use almost every flight; once verified.

JPI uses Fuel Flow, RPM, OAT, MAP, and a pre-defined contstant to calculate %HP.  Once the constant is set (a configuration step in the EDM setup) and verified, I find the %HP very useful.

I am moving to a G500 TXi system and their EIS (engine information system) for the TXi does not have this capablity, so I decided to install a JPI instead.

[Bryan]

Duplicate post - deleted

[smccray]

9 minutes ago, Bryan said:

I disagree.  My %HP is something I use almost every flight; once verified.

JPI uses Fuel Flow, RPM, OAT, MAP, and a pre-defined contstant to calculate %HP.  Once the constant is set (a configuration step in the EDM setup) and verified, I find the %HP very useful.

I am moving to a G500 TXi system and their EIS (engine information system) for the TXi does not have this capablity, so I decided to install a JPI instead.

What does % hp give you?  Add the EIS you get a fuel range ring- engine operating outside the red box and you know if you have enough fuel to make it my looking at the screen. 

The EIS is far from perfect, but I like the integration with the Garmin systems. 

[carusoam]

%hp took years to develop... at least when it comes to our scale of Mooney power management...

It seams like it was a novelty to some... hard to believe for others...

It is hard to believe when the temps are cold, and a number larger than 100% is being displayed...

It would be good to have a DA display to go with that...

Wonder how often people send in their JPI to get a new software update?

Nice sets of data, LV!    You can even chart HP that was being used at various points of the flight... 

CHTs were really interesting after the leaning was done...  there was a race to see which cylinder could get cooler...

AI and engine monitoring... almost as good as the real thing... 

PP thoughts only...

Best regards,

-a-

 

[gsxrpilot]

%HP ensures I know where the "red box" is. With our turbos, the red box is a factor all the way into the high flight levels.

With my JPI talking to my IFD there is a fuel range ring displayed at all times. And it changes as I go from full rich climb, to ROP fast cruise, to LOP max range cruise.

[Bryan]

46 minutes ago, smccray said:

What does % hp give you?  Add the EIS you get a fuel range ring- engine operating outside the red box and you know if you have enough fuel to make it my looking at the screen. 

The EIS is far from perfect, but I like the integration with the Garmin systems. 

Like @gsxrpilot said, with the turbo - we can get 100% HP up to the flight levels. With my 252, I fly almost by %HP to know what my engine is doing. By flying %HP, I don’t have to guess (or calculate) where the red box/fin is based on the variables used in the JPI. If I want to be conservative I fly 65% LOP, if I want to fly fast I use 75% ROP.

I seriously considered the EIS but it did not give me the data I wanted to see in-flight. The JPI feeds the rest of my Garmin equipment (G500 TXi, and 750) to give me fuel required, time to empty, fuel at destination == basically everything I need in-flight. I don’t need a ring to see how far I can theoretically fly. I have digital fuel senders and reliable JPI 930 for that.

[smccray]

2 hours ago, gsxrpilot said:

%HP ensures I know where the "red box" is. With our turbos, the red box is a factor all the way into the high flight levels.

With my JPI talking to my IFD there is a fuel range ring displayed at all times. And it changes as I go from full rich climb, to ROP fast cruise, to LOP max range cruise.

Very cool that Avidyne incorporated that into the IFD.

1 hour ago, Bryan said:

Like @gsxrpilot said, with the turbo - we can get 100% HP up to the flight levels. With my 252, I fly almost by %HP to know what my engine is doing. By flying %HP, I don’t have to guess (or calculate) where the red box/fin is based on the variables used in the JPI. If I want to be conservative I fly 65% LOP, if I want to fly fast I use 75% ROP.

 I seriously considered the EIS but it did not give me the data I wanted to see in-flight. The JPI feeds the rest of my Garmin equipment (G500 TXi, and 750) to give me fuel required, time to empty, fuel at destination == basically everything I need in-flight. I don’t need a ring to see how far I can theoretically fly. I have digital fuel senders and reliable JPI 930 for that.

 

No doubt- makes total sense.  My A36 is turbo normalized, so I understand the need to track the engine parameters all the way up.  Flying LOP, you know HP based on the fuel flow.  I also suspect that you're not using continuously variable settings for RPM and MP.  You have your normal SOP for engine operations in each phase of flight.  If the CHTs start creeping up in cruise, you lean slightly more (if LOP) to cool off the engine.  If TIT is running hotter than normal, adjust settings a bit to cool off the TIT.  It's all small tweaks- the actual % HP probably doesn't matter much.

I put an 830 in my Mooney.  It was a great piece of kit.  I considered the 900 in the A36 instead of the EIS for the screen real estate.  Ultimately I decided to go all Garmin and the integration that comes with one platform.  I see a lot of reasons to stick with the JPI, particularly for a turbo airplane.  You can't get a numerical value for TIT on the EIS- it's insane.  I don't really understand the % HP factoring into the decision for me.  The good news is that both the %HP and the TIT display are on the development path for the G500 txi software.  However, I always caution anyone from buying from aviation vendors based on features in development.

[Bryan]

9 hours ago, smccray said:

No doubt- makes total sense.  My A36 is turbo normalized, so I understand the need to track the engine parameters all the way up.  Flying LOP, you know HP based on the fuel flow.  I also suspect that you're not using continuously variable settings for RPM and MP.  You have your normal SOP for engine operations in each phase of flight.  If the CHTs start creeping up in cruise, you lean slightly more (if LOP) to cool off the engine.  If TIT is running hotter than normal, adjust settings a bit to cool off the TIT.  It's all small tweaks- the actual % HP probably doesn't matter much.

I put an 830 in my Mooney.  It was a great piece of kit.  I considered the 900 in the A36 instead of the EIS for the screen real estate.  Ultimately I decided to go all Garmin and the integration that comes with one platform.  I see a lot of reasons to stick with the JPI, particularly for a turbo airplane.  You can't get a numerical value for TIT on the EIS- it's insane.  I don't really understand the % HP factoring into the decision for me.  The good news is that both the %HP and the TIT display are on the development path for the G500 txi software.  However, I always caution anyone from buying from aviation vendors based on features in development.

I had an JPI 830 prior to the installation of the TXi and found the data much eaiser to read and disciminate from the factory 700.  No, I am not continuly chaning my RPM and MAP during flight.  I have a set numbers I go to for 65%, 75%, LOP and ROP operations but because those are based also on FF and OAT, I like having the %HP quick calcualtion on my screen.

 I asked Trek (Garmin) about the TIT and the %HP for the EIS in multiple private messages when ordering my TXi, and he told me the TIT (number) was planned in a future release but no plans for %HP.  That was enough for me to decide against the EIS for now,  even though I would love to save the panel space.  I decided I was not going to *wait* for future development and decided on the JPI 930 with rebate.  I figure I can replace the JPI 930 (head-unit) with the EIS by only cutting a new planel  and re-using JPI probes. I think there is one (or two) JPI probles that are not compatible with the EIS.  I hope they update it to the level of the JPI.

[johncuyle]

18 hours ago, gsxrpilot said:

%HP ensures I know where the "red box" is. With our turbos, the red box is a factor all the way into the high flight levels.

With my JPI talking to my IFD there is a fuel range ring displayed at all times. And it changes as I go from full rich climb, to ROP fast cruise, to LOP max range cruise.

Hm.  I haven't got mine dialed in yet and haven't incorporated it into my flying.  If I'm climbing I'm full rich and if I'm in cruise I'm LOP, so I operationally I just use FF as a proxy for HP.  My original point was more that if you haven't gone through and made absolutely sure that the %HP is accurate, it may not be accurate.  Savvy traces are the only thing that helps when diagnosing an issue.

[PT20J]

Interesting that the guys that championed LOP operation and promulgated the red box concept have said they don’t see much use for percent power. 

Most of us learned to fly using power settings based on percent power and clearly many still do. For those that don’t — how do you decide where to park the throttle, prop, and mixture?

[231LV]

On 4/19/2019 at 8:23 PM, PT20J said:

Interesting that the guys that championed LOP operation and promulgated the red box concept have said they don’t see much use for percent power. 

Most of us learned to fly using power settings based on percent power and clearly many still do. For those that don’t — how do you decide where to park the throttle, prop, and mixture?

well....on my 231, it's full rich and no more than 37 MP on takeoff and climb with FF around 25 gph and in cruise, 2500 rpm, 10 gph FF and around 32 MP...at 18k ft, that is good for about 175KTAS...somewhere around 66% HP ..many LOP guys have learned that FF is a pretty good indicator of where things stand...a quick glance at CHT's confirms...the rest is "tweaking". LOP isnt faster than full rich or heaven forbid , 50 ROP,  but its much more economical.....

Edited April 30, 2019 by 231LV

[jlunseth]

Hi all.  My plane has been in the shop for the annual and CiES senders and I have been working my tail off, so have not been here much.  %HP when LOP is fuel flow in GPH x 13.7 divided by rated HP (210 for the 231).  Everyone should know that by now.  The JPI uses that formula when LOP, or at least that is the way it appears to me.  

I saw some posts wondering how you know you are actually LOP.  Using the JPI’s you can’t start on the rich side, pull everything over to the LOP side, and expect to have a good “degrees lean of peak” reading because in the 231 too many things are moving around.  In the aircraft that control MP so it is constant when fuel flow is reduced that is possible, but in the 231 a change to MP changes fuel flow and vice versa, so by the time you get from the ROP side to the LOP side everything has changed and the peak reading you got is no longer valid.  The one way to do it and get a decent number is to get the engine running on the LOP side for sure, say 10 GPH and 32-34”, and then use the JPI in Rich of Peak leaning mode to enrich to peak and back.  Rich of Peak mode does not actually know whether you are rich or lean of peak.  It is JPI’s way of determining peak by measuring the first cylinder to peak, and if you are already on the lean side and enriching back to peak, that is what you want.  Then when you lean back again, you are measuring degrees from peak by the cylinder that is closest to peak, making sure all the rest are further away.  This is still not perfect, because as I said, when you make a change to fuel flow or MP in the 231, it changes other things.  But it is reasonably accurate.  Once you are confident you know what a good LOP setting is, then just use MP and FF to make it again the next time, its simpler.

[carusoam]

1) Essentially we are trying to adjust FF/air flow ratio....  

2) peak EGT will occur at the same FF/AF ratio.

3) In an NA engine, our air flow stays constant with a constant MP, which stays constant with altitude... so we adjust the mixture knob as if we are solely adjusting FF...

4) In a TC’d Engine, our AF changes itself as we adjust the mixture... as indicated by the MP...

5) With the NA engine... whenever we change altitudes... a mixture adjustment is going to be in the works...

6) To lean the same way with a TC’d engine, the MP would need to be held constant... (adjusted back to the selected MP). Watch the EGT rise with the FF decreasing... while adjusting the MP to stay constant...

7) it is going to be confusing if you start decreasing the mixture and the MP drops... when you see the TIT drop and MP drop and %hp drop...

8) The whole idea is to maintain a high level of MP, so excess air is used to cool the TIT, not excess fuel like like ROP...

9) So... if leaning your engine and the MP dropped, and peak was not well determined....I think I can see how something got lost in the leaning procedure...

PP thoughts only, not a mechanic...

Best regards,

-a-

[smccray]

On 4/19/2019 at 10:23 PM, PT20J said:

Interesting that the guys that championed LOP operation and promulgated the red box concept have said they don’t see much use for percent power. 

Most of us learned to fly using power settings based on percent power and clearly many still do. For those that don’t — how do you decide where to park the throttle, prop, and mixture?

It's not that % power isn't relevant, it's just a simple multiplier based on fuel flow.  However- how do I decide where to park the throttle?  I fly WOT, prop at 2500 RPM, then adjust fuel flow to push as much fuel through the engine as I can while keeping TIT (and other engine temps) in a safe range and outside the red box.  More power!!!   If I need more range I can pull the prop back to 2300 RPM on possibly lean a little more, but that's looking for efficiency.  I watch the fuel range on my flight instruments, and I replaced the fuel senders with digital senders that have proven to be very accurate.  I typically fly with excess fuel so range has not been a problem for me.  Depending on the flight profile I may use a LOP climb (which is more efficient) or slow down a bit in the name of efficiency, but most of the time I pushing to get to my destination as soon as possible, or to get home in time to see my kids before they go to bed.  I accept the higher fuel bill in the name of time.  The extra fuel probably doesn't make that much difference to block times, but I'll take it :).

My J I flew WOT normally at 8-10K ft looking for cooler temps.  Fuel Flow was set based on peak EGT.

The K (much of the conversation here)- that's clearly a different game with the throttle setting and one I don't understand since the K isn't flown WOT.

[231LV]

On 4/18/2019 at 3:58 PM, kortopates said:

Scott @231LV,

Now we're getting somewhere. But in a sense, you are still getting ahead of yourself, trying to run LOP without collecting the data. I don't mean that critically, but just stating the facts you need 2 things to be able to run LOP and they both need to be verified independently. (perhaps you already did this before since you mentioned an overhaul - but if so that data is stale at this point). But that is what the Savvy test profile is for - to check out your mixture distribution and ignition system. Which is why several folks above that have all been down this road have been giving good advice. Right now I wouldn't even focus on TIT, you need to be looking at EGTs and I see you got some decent data to start. 

Zoom into 10:30 where you leaned out the engine from ROP to LOP and measure your Gami spread.

I get the following:

Time: 00:10:28-00:11:32

EGT5 peaked at 10

EGT6 peaked at 9.9

EGT3 peaked at 9.6

EGT4 peaked at 9.5

EGT1 peaked at 9.4

EGT2 peaked at 9

GAMI spread is 1.0

A gami spread of 1.0 isn't sufficient to run LOP  - your leanest cyl will flame out, actually seriously start missing, while you're trying to get your richest cyl lean enough. Keep in mind 1 gami spread isn't enough data to make any conclusions. We need to see consistent, repeatable spreads. So I only only refer to your data as an example. In the above data, Cyl #2 (almost) appears as a rich outlier, but it looks like you may need more than one swap to get your mixture to <0.5 GPH. But maybe not, when we discard #2 mixture comes in at 0.6 GPH - pretty close to our target 0.5 - we still need a lot more data.

I said almost about #2 being a rich outlier, but it has another issue which tells me we really don't know where Cyl 2 is peaking (especially on only 1 gami spread). You notice how EGT2 keeps rising as you lean? well that is a sign of misfire; which could be due to a weak or dirty plug in #2. But that is what the LOP mag test is for - to independently assess the health of each plug and your ignition system as a whole. Ideally this should be done at 50F LOP, But I expect you'll get roughness before you are able to lean that much so just go as far as you can with a smooth engine and then isolate each mag for a minimum of 10 data points or 30 sec. I expect we'll see some misfire in #2 - which should be easy to address if so. But its looking like to me, that you'll probably have to correct any ignition defects before you can get any accurate gami spread data.

But get several gami sweeps done real slowly in both directions from ROP to LOP and back to ROP, followed by the LOP Mag test after slowly going ROP to LOP so you can tell how LOP the test was done - since it puts the results in context.

Once you get past any ignition defects and can get good repeatable  gami spreads, then you can email your results to John-Paul at Gami and he'll be able to get you what injector swap(s) you may need to get good mixture.

But before you collect any more data I suggest you also re-set your EDM sampling rate from its default 6 sec rate to every 1 sec, it will improve the data resolution and improve the diagnostic value tremendously. (The instructions on how to do this in the Savvy Test profile are really for the 730/830 - its a little different in the 900 but close)

http://content.savvyanalysis.com/static/pdf/SavvyAnalysisFlightTestProfiles.pdf 

 

Finally, I have a potentially good answer as John-Paul and I have been speaking about data I have been sending him. Basically, after looking at the data, he is sending me a leaner #2 and richer #5, #6 nozzles. My spread has been as wide as 1 gph and he is pretty confident that this swap will get me within .5 gph or lower. Obviously, this should also allow me to run deeper  into LOP which should lower my TIT. I still have not done an ignition test up high (but plan to) but John-Paul said it is not necessary from the data he is looking at. I did reset my JPI to record at 1 second intervals, as well. I want to again thank all you guys for weighing in with your thoughts regarding this initial issue. The collective knowledge of this forum is stunning. I am still learning to fly the airplane with the Merlyn (which is a totally different animal than a fixed waste gate) but the JPI is giving me a wealth of information I didn't really have with the JPI 800 (or maybe I just didnt understand it). The non-turbo guys who spoke up here are also appreciated for being willing to try and share their thoughts....turbo's are a completely different animal and have to be flown in a manner not consistent with the N/A engines. I am still tweaking the FF but we are really close....I think another 1/4 turn richer will get me to the "sweet spot" of 25 gph at 37 MAP and drop my CHT's on climb out to well below 380 degrees.

[kortopates]

4 hours ago, 231LV said:

Finally, I have a potentially good answer as John-Paul and I have been speaking about data I have been sending him. Basically, after looking at the data, he is sending me a leaner #2 and richer #5, #6 nozzles. My spread has been as wide as 1 gph and he is pretty confident that this swap will get me within .5 gph or lower. Obviously, this should also allow me to run deeper  into LOP which should lower my TIT. I still have not done an ignition test up high (but plan to) but John-Paul said it is not necessary from the data he is looking at. I did reset my JPI to record at 1 second intervals, as well. I want to again thank all you guys for weighing in with your thoughts regarding this initial issue. The collective knowledge of this forum is stunning. I am still learning to fly the airplane with the Merlyn (which is a totally different animal than a fixed waste gate) but the JPI is giving me a wealth of information I didn't really have with the JPI 800 (or maybe I just didnt understand it). The non-turbo guys who spoke up here are also appreciated for being willing to try and share their thoughts....turbo's are a completely different animal and have to be flown in a manner not consistent with the N/A engines. I am still tweaking the FF but we are really close....I think another 1/4 turn richer will get me to the "sweet spot" of 25 gph at 37 MAP and drop my CHT's on climb out to well below 380 degrees.

Sounds good. But don't be disappointed if it takes another swap to get it good. Coming from this far out its not unusual to take a couple rounds of swaps but this should get you real close. 

[johncuyle]

15 hours ago, smccray said:

It's not that % power isn't relevant, it's just a simple multiplier based on fuel flow.  However- how do I decide where to park the throttle?  I fly WOT, prop at 2500 RPM, then adjust fuel flow to push as much fuel through the engine as I can while keeping TIT (and other engine temps) in a safe range and outside the red box.  More power!!!   If I need more range I can pull the prop back to 2300 RPM on possibly lean a little more, but that's looking for efficiency.  I watch the fuel range on my flight instruments, and I replaced the fuel senders with digital senders that have proven to be very accurate.  I typically fly with excess fuel so range has not been a problem for me.  Depending on the flight profile I may use a LOP climb (which is more efficient) or slow down a bit in the name of efficiency, but most of the time I pushing to get to my destination as soon as possible, or to get home in time to see my kids before they go to bed.  I accept the higher fuel bill in the name of time.  The extra fuel probably doesn't make that much difference to block times, but I'll take it :).

My J I flew WOT normally at 8-10K ft looking for cooler temps.  Fuel Flow was set based on peak EGT.

The K (much of the conversation here)- that's clearly a different game with the throttle setting and one I don't understand since the K isn't flown WOT.

Where to park the throttle in a K model is not that hard.  In cruise, assume you'll want to run LOP.  In an engine with good fuel distribution, for a given MP you can run it very lean.  If you've taken the APS course, one of the curves on the EGT graph is BSFC.  Here's the graph in another post: 

Bottom line.  Ignore the absolute CHT values here.  You can see that it bottoms out at around 65dF LOP.  HP drops off significantly after that.  You get good fuel consumption up through peak.  In general, you want to park the throttle at an MP that allows you to be about 35-50dF LOP at your target cruise FF, keeping in mind your TIT limits.  Some experimentation will be necessary to figure out exactly where this is on the K model because throttle also changes FF and it is difficult to know exactly how LOP you are, but in general once you've figured out two or three cruise profiles (say, a 10.5 GPH "fast" profile and an 8.5 GPH "economy" profile) you more or less just set the MP and FF and watch the EGT/CHT/TIT to make sure nothing is reading out of the ordinary.

[231LV]

Happy to report that after swapping 3 injectors provided by GAMI, the GAMI spread dropped from 1 gph to .2 gph......I am able to lean the engine to 9 gph running 64% power LOP...hottest jug is 344 and 1536 EGT....TIT dropped down to 1600......

[gsxrpilot]

And your engine will love you for it! 

[N231BN]

15 hours ago, 231LV said:

Happy to report that after swapping 3 injectors provided by GAMI, the GAMI spread dropped from 1 gph to .2 gph......I am able to lean the engine to 9 gph running 64% power LOP...hottest jug is 344 and 1536 EGT....TIT dropped down to 1600......

A couple comments...9 gph LOP is closer to 58% power (9 X 13.7 / 210). Also, looking at the savvy graph I see you are running only 26.9" MP. At that setting, I don't think you are as lean as you think. I know you have an intercooler but try adding a couple inches and your TIT and EGTs should come down some more. What RPM are you running there?

[231LV]

2 hours ago, N231BN said:

A couple comments...9 gph LOP is closer to 58% power (9 X 13.7 / 210). Also, looking at the savvy graph I see you are running only 26.9" MP. At that setting, I don't think you are as lean as you think. I know you have an intercooler but try adding a couple inches and your TIT and EGTs should come down some more. What RPM are you running there?

I will give your suggestions a try...2500 rpm....I could probably run leaner as at 9 gph...there was no stumble at all...the algorithym for HP on the JPI 900 showed 64% power but you are using the correct formula...