PMDG 737 Navigation Display showing wrong ALT difference

[Konterhalbe 296]

I'm just on my way from EGKK to CYDF and I've just stumbled across something really strange...

VATspy is showing me on FL400 (39700 ft adjusted to local QNH) which is correct.

Traffic accompanying me on a different NAT is on FL320 (31700ft adj. to lcl QNH)...

 

After staring 4hrs on my ND feeling that something's odd, I realized that his traffic symbol is not only off by a couple 100ft, but by 2600ft.
When I'm on FL400 and he's on FL320, the diamond should read -80 or have I lost my ability to do basic math?

I had a chat with him and he's on standard QNH 1013 and confirmed he's on FL320 too.
Later, he climbed by 2000ft to FL340 and my ND showed me -34 instead of -60.

Never noticed this before in the PMDG 737.
Could this be linked to the MSFS beta program I've opted in recently?
Or has the latest PMDG update gone wrong?


Anyone else having this? 👀👀

[mwilk 1,107]

You might want to bring this up over on PMDG's official forum where a developer would see it, or open a support ticket with them.

[btacon 1,850]

Don’t know if same/same but might be related. Give this topic a scan. 
-B

 

 

[Stearmandriver 2,332]

Interesting.  I've never seen this, but I've seen traffic be displayed correctly many times on their ND, so if this is a PMDG issue it is a new one.  

[LRBS 949]

There is an FMC option under  DISPLAYS page 6 where you filter traffic, range and ALT SEPARATION.

Did you try that?

And when using FL you just switch to STD, not adjusting "to local QNH"

Edited December 28, 2022 by LRBS

[Konterhalbe 296]

At the FMC setup - AIRCRAFT - DISPLAYS I've set the filter to 40nm and 9990ft alt separation. I'm using these settings since I started to fly the 737 again in MSFS and it worked perfectly for months. Haven't tried different settings here 'cause it worked perfectly fine for the last 58 flights.

 

What just comes to my mind: I've set FILTER to 40nm lateral and 9990ft vertical in every livery I'm using (TUI fleet consisting of D-A... BBD, BKM, BKN, BMV, HFI, HFO, HFU, HFV, HFX, SUN, TUA, TUC, TUF, TUH, TUI, TUN, TUO, TUR and TUZ) sometime back in October.. These settings remained saved at all ACFT until I discovered a couple days ago, that the majority of those aircraft have lost the altitude separation filter and got reset to I think what was 2000ft or so. What's really strange is, three aircraft of them (D-ABKM, HFI and TUR) still showed the 9990ft filter I had set couple months ago but all the others have lost it and got reset.

Super strange to me but it does not seem like a MSFS or VATSIM problem but a PMDG problem instead, innit?
I was just curious, is anyone else having this with the latest PMDG verison 3.0.54 or is it just on my side?

[pete_auau 1,168]

20 minutes ago, Konterhalbe said:

At the FMC setup - AIRCRAFT - DISPLAYS I've set the filter to 40nm and 9990ft alt separation. I'm using these settings since I started to fly the 737 again in MSFS and it worked perfectly for months. Haven't tried different settings here 'cause it worked perfectly fine for the last 58 flights.

 

What just comes to my mind: I've set FILTER to 40nm lateral and 9990ft vertical in every livery I'm using (TUI fleet consisting of D-A... BBD, BKM, BKN, BMV, HFI, HFO, HFU, HFV, HFX, SUN, TUA, TUC, TUF, TUH, TUI, TUN, TUO, TUR and TUZ) sometime back in October.. These settings remained saved at all ACFT until I discovered a couple days ago, that the majority of those aircraft have lost the altitude separation filter and got reset to I think what was 2000ft or so. What's really strange is, three aircraft of them (D-ABKM, HFI and TUR) still showed the 9990ft filter I had set couple months ago but all the others have lost it and got reset.

Super strange to me but it does not seem like a MSFS or VATSIM problem but a PMDG problem instead, innit?
I was just curious, is anyone else having this with the latest PMDG verison 3.0.54 or is it just on my side?

have you  opened up a support  ticket  at pmdg  since  they  the  ones  will be  able  to fix  the  issue  if its  one  at all

[LRBS 949]

54 minutes ago, Konterhalbe said:

 

 

What just comes to my mind: I've set FILTER to 40nm lateral and 9990ft vertical 

I would try ALT SEPARATION set to 2800FT, kind of standard.

[jcomm 6,011]

I believe the values in delta alt are geometric, not pressure, for safety reasons.

Under cold air the actual distance (height) between geopotential levels will shrink, so, instead of the expected -80 you might well get that -54

MFS has been modelling geopotential height variation with T since release, and since it was initially buggy the same Wonder-Team 🙂  WT made the necessary corrections some SUs ago.

It is a very nice simulation of geopotential height variation, better than in any other desktop general purpose flightsim I have used so far.

Edited December 29, 2022 by cagarini

[Konterhalbe 296]

9 hours ago, pete_auau said:

have you  opened up a support  ticket  at pmdg  since  they  the  ones  will be  able  to fix  the  issue  if its  one  at all

Yeah I did and I feel the need to further clarify that it's got nothing to do with MSFS AI traffic:
"Can you check when you fly over land, Europe or US what the difference is on the TCAS targers? As far as I know the sim uses the local QNH everywhere for AI traffic and if the QNH is to big or to low this could result to issues you see."

I'm on EPMO-EKRN right now to check the difference over land to other traffic as told by the PMDG support.
Traffic is on FL370 but showing +78:

 

Even when I switch from STD to LCL QNH 1007, traffic is off:

[Konterhalbe 296]

2 minutes ago, cagarini said:

I believe the values in delta alt are geometric, not pressure, for safety reasons.

Under cold air the actual distance (height) between geopotential levels will shrink, so, instead of the expected -80 you might well get that -54

MFS has been modelling geopotential height variation since release, and since it was initially buggy the same Wonder-Team WT made the necessary corrections some SUs ago.

It is a very nice simulation of geopotential height variation, better than in any other desktop general purpose flightsim I have used so far.

But if so, the whole traffic target symbols on the ND would be obsolete, wouldn't they?
I could be flying FL380, ND showing TFC at -15 while it's actually flying 1000ft above me.

In cruise, all other traffic ever got shown correctly (+10, -30, +40 etc) except when other traffic had not set STD Altimeter, then it showed +12, -27, +41 etc.
Don't know what's going on since a couple days. 😪

[Konterhalbe 296]

Traffic on FL350 showing +56 instead of +50 🤔

[jcomm 6,011]

TCAS - REL vs ABS altitudes disagree - Systems - AEROSOFT COMMUNITY SERVICES

[Konterhalbe 296]

9 minutes ago, cagarini said:

TCAS - REL vs ABS altitudes disagree - Systems - AEROSOFT COMMUNITY SERVICES

I was aware of that bug in the past. Ross Carlson then has updated vPilot some time in the past to match with MSFS pressure logic and it was all good from then until now.

https://forums.vatsim.net/topic/31832-altitude/page/2/

https://forums.flightsimulator.com/t/vatsim-ivao-pilotedge-users-be-aware-of-an-important-bug/426142/363

 

I've also updated vPilot to v 3.4.8 couple days ago, so maybe something changed at vPilot's side?

[Konterhalbe 296]

PMDG support is quick: "Will ask the team to check if anything changed from Asobo side on this. We had this nailed but seems either after SU10 or SU11 there was a chnage...."

 

Anyone else having this issue?
And if yes, which vpilot version and which PMDG Version are you using?
And are you in MSFS beta or on stable?

Edited December 29, 2022 by Konterhalbe