Further Engine ITT adjustments

[autogyro 18]

I've spent a bit of time fooling around with the xml gauges and aircraft.cfg files to try and tweak the Carenado PC12. I know Nick's been working on a proper solution, however in his current absence, I'm happy to share my findings.

 

I don't really have a good understanding of the interaction of the .air file's EGT and ITT changes, however visually I'm trying to fix up the gauge readings so at least you can adjust the throttle positions based on ITT and throttle readings when at altitude.

 

Does anybody have any good information sources for ITT vs fuel flow vs torque at different attitudes and altitudes?

 

At present I am just working off the Carenado Performance Tables,

 

Flying at 30,000 ft at -44 degC outside temp and 8000 lbs, fuel flow should be 327 lb/hr, speed 157 knots.

 

As you can see from the screenshot below, I've gotten close to this - but haven't really tested at all altitudes and levels. You will note the VC ITT temps have not been changed, but the pop up ITT has been changed - and it is really simple - I've amended the gauge to include for the effect of increasing ITT with increasing altitude.

 

Should the Carenado Performance tables be relied upon? Does anybody else have ITT vs altitude or at least some suggestions at what point you move from being torque limited to ITT limited?

 

I still need to test this at different altitudes though so it's very much work in progress.

 

Thanks.

 

 

 

 

 

[autogyro 18]

Ok, some good progress today.

 

Note the VC panels have not been fixed yet, but should be a relatively easy task. Just want to make sure the pop up appears correct. I'm writing these changes into the standard SP1 files. Edit: Correction - was editing based on Nick's XML files, which corrected the fuel Lbs display. Hopefully this won't be an issue if I use his XML files and all credit to him for that fix.

 

I've figured out Carenado has actually written the engine ITT display wrong, as in the maths behind how the gradations are displayed is wrong. I'm not sure if Nick or Bert had corrected this in the updated gauge XML files. I've corrected it now on my gauge. I only noticed it today, you'll even see it on the pop up display in the picture I linked above - the ITT is showing 720 degC but the analog shows more around 660 DegC. You'll notice this on your default gauges - check what the analog display shows corresponding to the ITT value - if the gauge isn't fixed, it won't be correct and won't pass the 500/600/700 degC tick marks in line with the displayed ITT value.

 

I've also noticed fuel flow that I've corrected is a tad high right around your typical cruise altitudes of about 16-24,000 ft, high by about 20 Lbs/hr. So I'll tweak it down a tad, but this will mean high altitude cruise, up around 26,000+ might be a tad conservative on fuel flow. I'll try and get a happy medium (maybe +/- 10 Lbs/hr at all altitudes).

 

Will post up the gauge changes and the aircraft.cfg file for anyone who would like to test.

[Boeing or not going 578]

Thank you! That bug has stopped me from flying. If you get the vc changed I will download and test.

[autogyro 18]

Ok, beta almost ready.

 

Please test it out at various altitudes/flight conditions and let me know your thoughts.

 

As you can see, VC and pop up gauges are now showing correct amounts and analog vs digital readouts match.

 

[HawkDsl 50]

So... the math test was a fail?  Huh.. Thank you for your work on this... I also had given up on this plane as well... what a shame.  The main thing is that Carenado got paid,.. They released a defective product, and didn't fix the recalls. It's very pretty though.

 

For the family station wagon, I finally got the F1 B200 Throttle stupidity fixed, and we are flying that around now... We just made a trip down to the inlaws to pick them up for the Dallas game on sunday. Upper level winds on the US east coast are in the hundreds... yes I said hundreds.. and going the wrong way!  But at least we're gonna be doing some Citation speeds on the way home!!

 

I'll be interested in your completed work... but you can fly it wide open even if the gauges were right.. you can't do that in the B200... it'll blow up... that's where I'm at now... planes that blow up if you fly them like a moron. you know... as real as it  (can) get.

[autogyro 18]

Beta 0.1 released! Hope this adds to your enjoyment of this aircraft. Despite some faults it is still a wonderful addition to FSX/P3D.

 

https://drive.google.com/file/d/0Bz_9RuK6jIkhYmg5cTJKSDVIeEk/view?usp=sharing

[HawkDsl 50]

 

 

Despite some faults it is still a wonderful addition to FSX/P3D

 

Thank you! and yes, it is a really nice plane.

[Boeing or not going 578]

Beta 0.1 released! Hope this adds to your enjoyment of this aircraft. Despite some faults it is still a wonderful addition to FSX/P3D.

 

https://drive.google.com/file/d/0Bz_9RuK6jIkhYmg5cTJKSDVIeEk/view?usp=sharing

 

I am reinstalling fsx again and going to try this out during the week. Thank you I am going to post feedback in a day or so. Anyone have replacement sounds?

[autogyro 18]

I've tried the Sonic Solutions PT6A soundset and although the rpm and turbine sounds are pretty good, I couldn't get the default Carenado prop growl in beta range to work with it (the Sonic Solutions soundest doesn't have any files for it). Probably just me setting something wrong though.

[Guest JustanotherPilot]

I've spent a bit of time fooling around with the xml gauges and aircraft.cfg files to try and tweak the Carenado PC12. I know Nick's been working on a proper solution, however in his current absence, I'm happy to share my findings.

 

I don't really have a good understanding of the interaction of the .air file's EGT and ITT changes, however visually I'm trying to fix up the gauge readings so at least you can adjust the throttle positions based on ITT and throttle readings when at altitude.

 

Does anybody have any good information sources for ITT vs fuel flow vs torque at different attitudes and altitudes?

 

At present I am just working off the Carenado Performance Tables,

 

Flying at 30,000 ft at -44 degC outside temp and 8000 lbs, fuel flow should be 327 lb/hr, speed 157 knots.

 

As you can see from the screenshot below, I've gotten close to this - but haven't really tested at all altitudes and levels. You will note the VC ITT temps have not been changed, but the pop up ITT has been changed - and it is really simple - I've amended the gauge to include for the effect of increasing ITT with increasing altitude.

 

Should the Carenado Performance tables be relied upon? Does anybody else have ITT vs altitude or at least some suggestions at what point you move from being torque limited to ITT limited?

 

I still need to test this at different altitudes though so it's very much work in progress.

 

Thanks.

 

 

Hi,

 

I notice in the image you  are at FL300, with a fuel flow of 326, but the fuel used is only 14, did you reset at some point after take-off.

 

steve

[autogyro 18]

Yep that's right, I'm keeping the plane at 8,000 lbs to match the book values for performance. So it is probably a bit after I reset the fuel.

So have been thinking about what else to adjust. The plane truly can be ITT limited now, but I'm not quite happy with the results yet, as hot weather performance is a bit atrocious when keeping ITT limited.

 

I've also now read that transition from torque limited to ITT limited should be around 13,000 ft, so I might tweak the ITT values a bit further to see if I can get close to this (it seems quite OAT dependent at the moment so I might introduce a variable to lessen this dependency.)

 

Once this is done, I'll work on scaling the effect of torque reduction with altitude if I can - at the moment I find you need to throttle UP to keep torque and ITT at the limit and from what I gather you should be throttling down from takeoff power once ITT limited.

[autogyro 18]

Ok, I'm happy with the cruise fuel flows at all altitudes.

 

ITTs, I'm also pretty happy with. However as you deviate more and more from ISA, the ITTs will vary more from the book values a bit - you'll probably want to climb a bit hotter in high temps (maybe up to 760 degC to keep the climb rate up), or might get torque limited in cold temps for a higher altitude.

 

I think for the most part the ITT performance is more in line with what can be expected of the PC12.

 

Beta 0.2 release (please use this version):

 

https://drive.google.com/file/d/0Bz_9RuK6jIkhc0hRMVJXaDFJZGc/view?usp=sharing

[autogyro 18]

No, ITT in the .air file is very limited.

 

Yes I am taking into account ITT increasing vs altitude, but in the xml gauge file.

 

Next on my list is adjusting torque drop off with altitude.

[autogyro 18]

Hi Jon_aus,

 

The gauge file is not that hard to work with - you can introduce a lot more variables to control how you want it to behave.

 

The two throttle vs torque vs IAP settings are 1503 and 1504 in the .air file. Since it's a turboprop, CN2 = CN1.

 

I've done an initial pass with the throttle settings, such that the torque drop off with altitude is reduced - in other words, you will need to retard the throttles as you increase in altitude, or at least this is my experience with the modded PC12 now.

 

https://drive.google.com/file/d/0Bz_9RuK6jIkhcTRrNmdBc19RQUk/view?usp=sharing

 

Beta 0.3 released. Getting closer to the 'correct' behaviour - from now on it should just be a matter of fine tuning to match book values (still looking for information from anyone who's familiar with the PC12 for power/torque/ITT settings at various altitudes and conditions).

 

Feedback would be appreciated. Thanks all.

[pve 0]

 

Nice work autogyro.

 

In the eng. gauge code GEN1 DC V shows BATTVOLTS at 24 and GEN2 DC V shows GENVOLTS at 28. I guess they both should be GENVOLTS. Easy to change.