A2A comanche vm1000c engine monitor

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russ
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Re: A2A comanche vm1000c engine monitor

#21 Post by russ »

I was looking at X-Plane datarefs for this instrument and after a short search I think I found most all except:

+ No individual CHT but only one value per engine

+ No carb temp that' I can see

+ No BHP or % HP so far

This is a very well done instrument so it would be nice to make it available in XP too.
It may also be a candidate for an Air Manager Raspberry Pi project as we look for ways to showcase that upcoming technology.

May I suggest that instead of modifying the Logic.lua for various airplanes that only a cloned and distinctively RENAMED copy be modified. Otherwise it is easy to accidentally update and overwrite the original version, especially when it makes it to the store. No reason we couldn't have various versions. Sometimes trying to write a universal version can get too messy especially since many of the XP datarefs in this case are arrays and the units are considerable different and in many cases ( like fuel flow in KG/sec. Vs. GPH )
Russ Barlow
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JackZ
Posts: 2262
Joined: Mon Feb 22, 2016 1:02 pm

Re: A2A comanche vm1000c engine monitor

#22 Post by JackZ »

Russ,since it is not my gauge, I only submitted the logic.lua, but of course the idea is to have 2 instruments (one A2A Comanche, one generic)
Feel free to modify my code at will to make it an XPlane gauge as well.

Don't know if the specific MIN/MAX variables including Tank capacities, Engine has Turbo and number of cylinders of each airplane can be derived from querying the sim.
Guess that there will always be some manual tweaking to adapt it to a generic airplane.

FYI in FSX/P3D there is no individual CHT/EGT values for each cylinder as well, so I cheated a little by introducing some random variations to the global values(+/- 15%) for each cyl.

And from my tests I found that carburetor Temp returned by FSX is not very relevant as well, since it is higher than the OAT???? One could calculate it loosely from the OAT, based on the throttle lever position/RPM (low RPMs yields the Max temperature decrease inside the carburetor, roughly DeltaTemp of minus 25 degrees C at idle, since the throttle valve is almost completely closed).
Anyway, the carburetor Temp is not used by the Peak calulations made by Arturo, so you can input whatever value you like. 8-)

There exists also a way to calculate %HP from other values, since SHP(Shaft Horse Power )=TorquexRPMx(2xPi)/60,
or SHP=KxMPxRPM, with K a constant according to my books and MP the Manifold pressure.

Jacques
Last edited by JackZ on Sat Mar 04, 2017 10:01 am, edited 5 times in total.
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JackZ
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Re: A2A comanche vm1000c engine monitor

#23 Post by JackZ »

Arturo

may I suggest a simple cosmetic correction in your instrument bezel?

The dropped shadows are not consistent on all the screws. Usually, sunlight comes from up and from the left, so the shadows should all go down and to the right.
Capture.PNG
thanks!

Jacques
My YouTube Chanel on the A320 (Real SOPs by an Airline Pilot IRL):
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alioth
Posts: 91
Joined: Tue Aug 16, 2016 9:03 pm

Re: A2A comanche vm1000c engine monitor

#24 Post by alioth »

Jacques, you are the man who never rest! :D

I have test the generic logic lua.
Things happening in my prepar3d with several planes (bonanza, maule, mooney..) :

- If Engine_Has_4Cyl = true... CHT Cyl#1 is always at red bar. It happens in boot up sequence too.
- Not any Cylinder blinks at all when red bar.
- the maximun temps I see in cht text is the set MAXCht. I doesnt have to be in this way. MAXCht tell you when the bar will blink, but the text must shows you the real temp, which can be higher than MAXCht, of course.
- In boot up sequence, I think than 6 cylinders must be seen ( and 6 egt). Boot up sequence shows you than all the leds in the panel are working (in the real one all are leds, it is not a digital display). This is the reason why when switch off, I made all the leds can be lightly seen. In the real one, yo can see it in this way. And this is the reason why in my comanche boot up sequence, TIT bar appears too. Comanche hasn't got TIT, but must appear in boot up sequence.
-In the last part of boot up sequence, TIT bar doesn't move slowly to the actual TIT target.
-TIT bar, first come to red... and later (some dregees higher) starts to blink. It must blink in the first time red.
-EGT temperatures ( I know you have write Farenheit in lvar), but this temperatures you are showing are sure celsius. You can easy confirm this with Maule EGT gauge. It can be used in Celsius, of course, although It is usually seen in farenheit.
- When 4 cylinders, you hide the cylinder #5 and #6 with img_oculta2CYL. It is ok. But you must make no visible my moving ocult-bars because the are behind and you can see how they are moving behind your img_oculta2CYL. (set brightness high in your monitor).
-Well done with TIT temperature. It shows the text "t" at the same time than higer cht. Like the real one.


I know It is not easy to control the whole thing when adding functions.

About CAT. It is true than is not well implanted in fsx/prepar3d.
A2A instead has perfectly simulated in its acusim planes.

A story based on real facts... Really, this happens to me yesterday night.
I was testing the comanche vm1000c. I flew LEIB-LEBB
In cruise, 6000ft, carb heat close. Autotrack ON. OAT and CAT the same. Behind 5ºC and start to rain.
Autotrack-manifolds blinks. Manifold is decreasing. Start to loose altitud. I know whats is happening. It is not the first time and I know this is simulated in A2A acusim planes-> Ice in carburetor. I open carburetor heat. I see the CAT temperature rising. One minute later Manifold has recovered and I smile. What a great Simulation moment!! thanks to a2a, and Autotrack :D

About HP%
If it can´t be calculated, perhaps it is better to simply show the % throttle level. Some planes, like Alabeo DA42 do this.
I think is better to have a real % throttle level, than a false %hp.
And I say this to prepar3d too. In the generic vm1000c with standard planes it shows 25% power at idle!!!!!. It is completely false. At idle, power % can't be more than 5%, never.
Again, comanche says 0,7%. They have this parameter simulated, and in flight, matches the table I posted, and the table power charts I have found about this O-540 engine!! Have I ever told you why Im buildind a cockpit around the A2A comanche??' :roll:


Arturo.

alioth
Posts: 91
Joined: Tue Aug 16, 2016 9:03 pm

Re: A2A comanche vm1000c engine monitor

#25 Post by alioth »

JackZ wrote: Sat Mar 04, 2017 9:46 am may I suggest a simple cosmetic correction in your instrument bezel?
True.
Perhaps It is better a simple phillips screw without shadows. I will do.
In mine I use real screws with real shadows 8-)

EDIT: Here it is.
With grey or dark screws.
Now the lit zone is in the bottom (bottom-right), as you said.
Attachments
New bezel. Dark screws.
New bezel. Dark screws.
New bezel. Grey screws.
New bezel. Grey screws.

JackZ
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Re: A2A comanche vm1000c engine monitor

#26 Post by JackZ »

Brilliant and efficient as ever, Arturo ;)

Thanks!

Jacques
My YouTube Chanel on the A320 (Real SOPs by an Airline Pilot IRL):
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JackZ
Posts: 2262
Joined: Mon Feb 22, 2016 1:02 pm

Re: A2A comanche vm1000c engine monitor

#27 Post by JackZ »

alioth wrote: Sat Mar 04, 2017 11:15 am - If Engine_Has_4Cyl = true... CHT Cyl#1 is always at red bar. It happens in boot up sequence too.
- Not any Cylinder blinks at all when red bar.
- the maximun temps I see in cht text is the set MAXCht. I doesnt have to be in this way. MAXCht tell you when the bar will blink, but the text must shows you the real temp, which can be higher than MAXCht, of course.
There is surely some improvements to be made. At first, I just wanted to try and port this gauge "as is" to FSX/P3D, it's YOUR gauge!.
I let you complement/debug the code if you agree on that, as I've spent too much time on this gauge like you said! ;) (AM programming is like a drug...)
alioth wrote: Sat Mar 04, 2017 11:15 am - In boot up sequence, I think than 6 cylinders must be seen ( and 6 egt). Boot up sequence shows you than all the leds in the panel are working (in the real one all are leds, it is not a digital display). This is the reason why when switch off, I made all the leds can be lightly seen. In the real one, yo can see it in this way. And this is the reason why in my comanche boot up sequence, TIT bar appears too. Comanche hasn't got TIT, but must appear in boot up sequence.
At first, I devised it the way you said (for 4 cylinders, everything including TIT is showed at startup), then changed my mind after viewing the real startup sequence in the video of JPi website you provided.
alioth wrote: Sat Mar 04, 2017 11:15 am -In the last part of boot up sequence, TIT bar doesn't move slowly to the actual TIT target.
-TIT bar, first come to red... and later (some dregees higher) starts to blink. It must blink in the first time red.
To tell you frankly, I haven't refined the TIT display sequence, I symply copied the one you use in the startup routine.
Feel free to modify it!
alioth wrote: Sat Mar 04, 2017 11:15 am -EGT temperatures ( I know you have write Farenheit in lvar), but this temperatures you are showing are sure celsius. You can easy confirm this with Maule EGT gauge. It can be used in Celsius, of course, although It is usually seen in farenheit.
- When 4 cylinders, you hide the cylinder #5 and #6 with img_oculta2CYL. It is ok. But you must make no visible my moving ocult-bars because the are behind and you can see how they are moving behind your img_oculta2CYL. (set brightness high in your monitor).
in fact according to the video, I should actually hide cylinder #1 and #6. This is corrected.
alioth wrote: Sat Mar 04, 2017 11:15 am -Well done with TIT temperature. It shows the text "t" at the same time than higer cht. Like the real one.
Thank you. Had a hard time to get it right in all configurations. Don't know if the EGT label is displayed while showing the TIT temperature, the documentation is not clear about taht.

BTW two (minor) cosmetic things I noticed:
- the EGT and DIF labels are inversed in the manual (EGT is on Top)
- And according to the manual, while in Peak mode, once the Peak has been reached both EGT and DIF are displayed, then EGT disappears.

Development is a never ending story!

Jacques
Attachments
logic.zip
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My YouTube Chanel on the A320 (Real SOPs by an Airline Pilot IRL):
https://www.youtube.com/playlist?list=P ... 0Q6SBASRqJ

JackZ
Posts: 2262
Joined: Mon Feb 22, 2016 1:02 pm

Re: A2A comanche vm1000c engine monitor

#28 Post by JackZ »

Well.... Couldn't leave it as it were, so here's the final version, from my side... At last!

Tit Bar:
- Correctly displays at startup with animation and in Turbo configurations only
- Red alarm bar flashes when TiT is too high

CHT:
-Modified the behaviour in 4 cylinders configuration where the numbering of cylinder was incorrect (engine cyl #1 is the first to the right)
- there is now the blinking cylinder when red bar CHT is reached

Jacques
Attachments
logic.zip
(11.12 KiB) Downloaded 205 times
Last edited by JackZ on Sat Mar 04, 2017 5:57 pm, edited 1 time in total.
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https://www.youtube.com/playlist?list=P ... 0Q6SBASRqJ

alioth
Posts: 91
Joined: Tue Aug 16, 2016 9:03 pm

Re: A2A comanche vm1000c engine monitor

#29 Post by alioth »

JackZ wrote: Sat Mar 04, 2017 5:14 pm - there is no blinking cylinder when red bar CHT is reached, as this has not been implemented???
It was implemented :)
You change some values, so cht and egt couldn't pass the MAX.
It is corrected now in this logic. The temperatures can jump higher than MAX, and Cylinders blink.

Thank you very much for the port. I will watch in detail in future. For now, it is more than perfect :)
At first, I devised it the way you said (for 4 cylinders, everything including TIT is showed at startup), then changed my mind after viewing the real startup sequence in the video of JPi website you provided.
True!!
- the EGT and DIF labels are inversed in the manual (EGT is on Top
You are correct, some things seem different in videos and manual. I have made like vid.
And according to the manual, while in Peak mode, once the Peak has been reached both EGT and DIF are displayed, then EGT disappears.
Correct. I will do it in that way. And Im going to do the (+) (-) in dif peak mode.

Thanks again!

Arturo.
Attachments
logic.rar
(10.36 KiB) Downloaded 203 times

JackZ
Posts: 2262
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Re: A2A comanche vm1000c engine monitor

#30 Post by JackZ »

Thanks to you Arturo.

You've made a very nice instrument and I learned a lot on how you dealt with flashing things!
The code could probably be slightly optimized, as there are LOTS of calculations (especially the EGT temp) which are done every time, but as it is it's already very satifactory.

Maybe someone (Russ?) will want to have a look at it and port to Xplane as well?

Jacques (back to normal life :lol: )
My YouTube Chanel on the A320 (Real SOPs by an Airline Pilot IRL):
https://www.youtube.com/playlist?list=P ... 0Q6SBASRqJ

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