Just now, fppilot said:

I have the mod in place.  

 

Like Viz stated, this is what I observed today.  Adjusted the altimeter and observed the target altitude change. 

And yet i cant see it, its the one thing that i cant wrap my head around with this new sim, how people doing the same things get different results. It happens with a lot of different issues with MSFS, as if we all had a different version of the sim. Weird.

9 minutes ago, leprechaunlive said:

And yet i cant see it, its the one thing that i cant wrap my head around with this new sim, how people doing the same things get different results. It happens with a lot of different issues with MSFS, as if we all had a different version of the sim. Weird.

And sometimes it is from one flight to another...

1 hour ago, fppilot said:

There in lies the flaw.  You may not be understanding the issue.  Perhaps read my recent post.  
 

Do this.  Set your altimeter at 29.92 (standard pressure).  Set a target altitude, say 5,000 ft.  Have the aircraft climb to and capture that altitude.  I will capture 5,000 ft based on my experience.

Now.  Assume the altimeter setting provided by ATIS/AWOS, or by ATC, is 30.17.  Set that pressure in the altimeter.  Set a target altitude of 5,000 and see where it captures.  It will not be indicated as 5,000 feet.  more like 5,250 or there about.  That is not right!  The altitude when captured should indicate 5,000 ft when the altimeter is set to the current pressure.  The issue pointed out by the OP indicates that in MFS it may be that the aircraft is actually be at a 5,000 ft altitude, but the indicated altitude may be the culprit.  There is a flaw somewhere.

I just did exactly this. I have completed two short test flights from my home airport, KELM. I spawned first in the C172 on the threshold of runway 24.

Tonight is a particularly glaring example of just how far “off” Live Weather can sometimes be, because it was giving a pressure of 29.65 and wind of 221 at 16, when the actual r/w METAR is pressure of 30.11 and wind 310 at 4. In fact, the current Live Weather would have been very close to accurate 24 hours ago, on WEDNESDAY night. This is a common problem I see when trying to use Live Weather in evening local (Eastern US) time - it often seems to provide data from the previous day’s MeteoBlue model. 

But... that is a different bug entirely and not directly relevant for the present test.

So, I hit B to sync the altimeter to the current pressure of 29.65, which gave an altimeter readout of 960 feet - exactly correct for the threshold of KELM runway 24.

I configured the autopilot to capture at an altitude of 5000 feet, and departed on runway heading with the autopilot in HDG mode and VS mode, with a climb rate of 600 FPM. As I approached 5000 feet, the altitude alert sounded at 4750 feet, the preselected altitude started flashing, and the FMA annunciator changed from white ALTS to green ALT. All exactly correct.

The aircraft leveled off at 5000 feet indicated, exactly as expected, and maintained it. There was a bit of turbulence as the wind at 5000 feet had increased to 225 at 24, but no question that the airplane was holding 5000 feet indicated. The barometric setting was still 29.65, and when I pressed B it did not change, so I was still in the same weather “cell” as at departure.

I then manually dialed the baro up to 29.92, which (as expected) caused the altimeter reading to increase to about 5,250 feet indicated. The autopilot immediately began a descent and shortly re-captured the indicated altitude of 5000 feet. I then pressed B to reset the altimeter to the correct current pressure of 29.65, which made the altimeter read 250 feet low. The autopilot initiated a climb, and recaptured the preselected 5000 feet indicated altitude.

Thinking that perhaps some MSFS aircraft operate correctly in this regard, while others do not, I repeated the test in the C208B, starting again at KELM runway 24. I did a full re-start of MSFS to insure that Live Weather would load correctly for the second flight. It did, and pressure was again 29.65.

The second flight was no different than the first. The Caravan captured at 5000 feet indicated altitude, with the baro set to the current ambient pressure of 29.65.

Installation, repair and maintenance of air data systems and autopilots is what I do for a living, so the performance of flight simulator avionics systems and the emulation of atmospheric dynamics is an area of particular interest to me, and something I pay very close attention to.

I have no doubt that the problem you have reported is in fact happening on your system, which is an example IMO, of why it is apparently so difficult for Asobo to get the sim “right”, when two individuals, running (apparently) the same software on two different computers can get two very different results when flying one of the default aircraft in exactly the same way.

All I can tell you is that in every iteration of MSFS from Alpha 1.5 to the current 1.9.0.3, the altitude capture has always worked exactly right for me on every default aircraft I have flown with altitude preselect capability. The aircraft always captures and maintains the altitude set in the preselect without fail, and does so no matter what the barometric pressure the altimeter is set to.

BTW, I have NO mods installed except the FBW A320N and Navigraph Beta simulator nav data.

Edited October 9, 20205 yr by JRBarrett

12 minutes ago, JRBarrett said:

BTW, I have NO mods installed except the FBW A320N and Navigraph Beta simulator nav data.

I have a G1000 mod in place.

Ok,  I have just run 2 test flights, and I can confirm that the problem exists with the working title g1000 mod installed, and does NOT exist in default.  default climbed to indicated altitude at various baro settings, and adjusted properly when changing barometer on the fly.  modded g1000 did otherwise as noted by others.

We are dealing with a new sim, which is a work in progress, and we have modders scrambling to try to fix stuff. that's fine.  However it is REALLY, REALLY IMPORTANT to disable mods while troubleshooting.

as well, there was some discussion about there being "no way" to get the baro settings in the air, wanted to mention that the default ATC, while horrible in many ways, does update you with altimeter settings in flight.

 

 

Edited October 9, 20205 yr by ShawnG

2 hours ago, ShawnG said:

I can confirm that the problem exists with the working title g1000 mod installed, and does NOT exist in default. 

Aha!

3 hours ago, ShawnG said:

Ok,  I have just run 2 test flights, and I can confirm that the problem exists with the working title g1000 mod installed, and does NOT exist in default.  default climbed to indicated altitude at various baro settings, and adjusted properly when changing barometer on the fly.  modded g1000 did otherwise as noted by others.

We are dealing with a new sim, which is a work in progress, and we have modders scrambling to try to fix stuff. that's fine.  However it is REALLY, REALLY IMPORTANT to disable mods while troubleshooting.

as well, there was some discussion about there being "no way" to get the baro settings in the air, wanted to mention that the default ATC, while horrible in many ways, does update you with altimeter settings in flight.

 

 

On your system 🙂 On mine WT G1000 works perfect, and the default one too 🙂

6 minutes ago, leprechaunlive said:

On your system 🙂 On mine WT G1000 works perfect, and the default one too 🙂

interesting,  what version of g1000 mod do you have?

 

Just now, ShawnG said:

interesting,  what version of g1000 mod do you have?

 

The last one i guess, the release they did to make it compatible with 1.9.3 🙂 But it seems to be a trend on MSFS, that same situations gives different result depending on the user, and  have to admit, i cant quite understand why its the case.

Just now, leprechaunlive said:

The last one i guess, the release they did to make it compatible with 1.9.3 🙂 But it seems to be a trend on MSFS, that same situations gives different result depending on the user, and  have to admit, i cant quite understand why its the case.

it looks like I have 0.3.0 of the mod, which was immediately after 1.9.3, (10/1)  and there was a 0.3.1, (on 10/5) so I'm not up to date.  I'll see if the new mod is better, probably not til tomorrow tho.  Their build notes do not mention fixing a baro/ap logic problem, but maybe they fixed it by accident.  

I know you're a leprechaun, but I don't believe in magic.  😀

2 minutes ago, ShawnG said:

it looks like I have 0.3.0 of the mod, which was immediately after 1.9.3, (10/1)  and there was a 0.3.1, (on 10/5) so I'm not up to date.  I'll see if the new mod is better, probably not til tomorrow tho.  Their build notes do not mention fixing a baro/ap logic problem, but maybe they fixed it by accident.  

I know you're a leprechaun, but I don't believe in magic.  😀

They mention a few things about the AP, but there nothing specifically about that so. Theres no magic involved (i think), but leprechauns are very lucky, so i guess thats why 😄 

8 hours ago, leprechaunlive said:

Nope, regardless of the altitude, the B method always sets the "real" or at least the weather engine oustide baro pressure. So unfortunately pressing B above 18000ft doesnt set it to 29.92 automatically. I kind of recall that FSX used to do it tho?

I never use the B key to set the altimeter pressure in FSX or now, P3D. Manual dialling required on Concorde and on the PMDG737 I press the pressure knob to set it to STD.

I wonder why they don't use different TAs when the data must be available. It's been present in Radar Contact for over 15 years.

2 minutes ago, Ray Proudfoot said:

I never use the B key to set the altimeter pressure in FSX or now, P3D. Manual dialling required on Concorde and on the PMDG737 I press the pressure knob to set it to STD.

I wonder why they don't use different TAs when the data must be available. It's been present in Radar Contact for over 15 years.

They kind of do it for vfr squawk, depending on where you are, when you press the vfr button on the squawk, it changes to 1200 or 7000 depending if your ICAO or FAA. So there are "regional" settings and parameters, and like you said, i shouldnt be too hard to include the TA in them.

18 hours ago, Ray Proudfoot said:

I should have qualified my earlier post by saying this is how it works in the real world. It sounds from the OP’s post that pressure can’t be set correctly in the aircraft. Should be a reasonably quick fix for the developers.

Ray, your absolutely correct.  That's the original point I was making and I agree it should be easily fixed by Asobo.

Paul

7 hours ago, ShawnG said:

as well, there was some discussion about there being "no way" to get the baro settings in the air, wanted to mention that the default ATC, while horrible in many ways, does update you with altimeter settings in flight.

 

I did try the ATC once, but the altimeter settings they gave were not correct. About 0.03 in/hg off based on comparison to “B”. Granted, that is not a serious disparity, and could easily happen on a real flight if the nearest airport is some distance away - but the default ATC is so bad I’d rather sit naked on a block of dry ice than use it.

Unlike many MSFS users, I am not disappointed by the state of the default ATC. I concluded long ago that NO flight sim developer has the ability to produce a built-in ATC system that is worth a pile of poo. FSX/P3D and X-Plane are little better in this regard. 

I do enjoy both Vatsim and Pilot Edge, and with those networks, syncing the altimeter with B is a must, since the controllers’ weather is likely to be very different than what Live Weather provides. Since online network controllers “see” the aircraft’s indicated altitude (unlike real Mode C where the aircraft transmits  its 29.92-referenced pressure altitude) it works out well. 

 

Edited October 9, 20205 yr by JRBarrett