NGX and IvAp => 2 annoying issues

[rbgomes 0]

Hello Everyone,

 

First of all, I apologise if this topic has already been discussed. I looked for the search engine in the forum, but could not find (sorry if it is in my face!).

 

I am experiencing 2 annoying bugs (?) with 737NGX and IvAp. One of them also happens with 777X. I use FSX:SE and before posting I updated both FSX:SE and 737NGX and 777X through a clean installation. Problems remain.

 

1) ON 737NGX AND 777X, when I connect to IvAp, I can NEVER get the IvAp METAR QNH to match the aircrafts when I am on the ground. For example, I am now online at EBBR, METAR QNH is 1020 and in the aircraft the QNH is 1010. 

 

Testes I made: I loaded default aircrafts and the QNH on them are CORRECT (1020) as per METAR. 

 

Any insights?

 

2) This one happens ONLY on 737NGX (in other words, all works perfectly with 777X!!!)

 

When online on IvAp, the embeded TCAS service with IVAN is NOT showing on the screen on 737NGX. Of course I thought it would be a FSUIPC problem BUT all works fine with 777X!

 

So, if settings are the same how can it work for 777 and NOT for 737??

 

Help appreciated.

 

Thanks!

Rafael

[SKeller 5]

I can help only with 1):

 

The altimeter will *NOT* automatically calibrate! The barometric pressure is not read by the aircraft at startup. The altimeter setting of the NGX/777 will always be the value that was saved with the panel state you use as your startup state.

 

So, once the aircraft and live weather has finished loading, you need to manually calibrate the altimeter to local QNH (simply pressing B on the keyboard will be the quickest way).

[rbgomes 0]

Thanks Steffan.

 

OK, suppose I use B and calibrate the altimeter. If I do not disconnect again, I should expect the weather to be "calibrated". So, during my Approach Checklist I set the local altimeter... well, after landing (suppose it was visual!), the altimeter will STILL be incorrect.

 

Any ideas?

 

Thanks again.

[SKeller 5]

It seems there's some kind of misunderstanding how altimeter calibration works ;-)

Pressing B will set the altimeter to the local QNH at your current position. It will not re-calibrate automatically when the QNH changes later. Remember that you probably pass through different weather conditions with different pressure in cruise.

 

Basically what you do is the following:

1. Set local QNH at your Departure Airport.

2. After takeoff, when passing Transition Altitude, set standard pressure (1013/29.92) and leave it there during climb, cruise and most of your descent, regardless of what the actual ambient pressure is. The idea is that all aircraft above TA use the same reference point for their altimeters.

3. When passing Transition Level during approach, set local QNH again (hit 'B').

 

That's it

[rbgomes 0]

Thanks Steffan,

 

I am considering ONLINE weather. When online, there should be no need to press B.

 

My issue is NOT offline. It is online with IVAO and ONLY with PMDG.

 

Thanks.

[SKeller 5]

Please trust me: There is no difference whatsoever between online and offline in this respect.

 

And YES, you need to calibrate your altimeter manually. Always. That's also true for real life by the way.

 

Your wheather in FSX will change automatically, yes. But your altimeter setting will NOT. And as said above, it's normally only three times you need to calibrate your altimeter during each flight:

1. On ground at your Departure airport prior to takeoff

2. When passing TA in climb

3. When passing TL in descent

And each time, you need to do so manually.

[rbgomes 0]

I can only thank you Steffan, but I have been in the SIM world for almost 20 years and with IVAO for almost 14.

 

I have been with earlier version of PMDG for a long time...

 

Things should work as I wrote above, as they always did.

 

As this is an official support forum, I will wait for an official reply.

 

Thanks again!

[SKeller 5]

Maybe I have completely misunderstood your problem?

 

Are you saying that the altimeter reading at the bottom right corner of the PFD does not match the reported QNH, but you think it should always match without any input by you?

 

Is this what you're asking for?

 

If so: It doesn't.

 

And by the way, since you played the experience card: I've been an IVAO member for 14.5 years now.

[rbgomes 0]

You misunderstood me

 

I will try to be more clear:

 

Suppose I am online and flying above the TA. I will see on the PFD lower right corner, in green, STD. I am flying on 1013.2 hPa. 

 

Now I am approaching my destination. I check the ATIS and the altimeter setting is, for instance, 1019.

 

I go to the smaller knob on the BARO MCP part and set 1019. On the lower right corner of the PFD, now, will appear in green STD and BELOW, in white, 1019 HPA.

 

Passing through TL, I only press the MCP STD button and it adjusts to Q1019, as I would do turning a knob on manual altimeters.

 

Now... since my online weather states that QNH at my destination is Q1019, I am adjusted. If I press B, nothing SHOULD happen, as what I did was a manual setting, as in real life.

 

Problem is, on the new version of both B737 and B777 for FSX:SE, this setting ends up being DIFFERENT from the weather found at the destination. And as this does not happen with default aircraft, it sure looks like some sort of problem with NGX and weather engine.

 

On IVAO forum there are a couple of posts reporting this problem. But I believe no one was able to pinpoint it to NGX as I did.

 

Older versions worked just fine as I described above.

 

Is it a bit clearer now ?

 

Thanks.

[SKeller 5]

Ah, NOW I'm with you

 

I've been flying the NGX since it's release, and I never observed this problem. Could this be a problem specific to FSX Steam? I'm on FSX Boxed. Maybe the Steam pilots have an idea.

 

But what you're saying is that pressing B will return different results depending on whether you're in the PMDGs or a default aircraft? This is very strange indeed...

 

Last try: Do you happen to have two weather engines active and running at the same time? E.g., you use ASN and forgot to uncheck the IVAO weather in IvAp Configurator?

[rbgomes 0]

I am glad I could make myself understood

 

I very rarely post, as I usually am able to solve the problems on my own... but not this time...

 

No, I do not have any other weather engine. Not even installed. That is why I believe it indeed is an issue.

 

Thanks.

[scandinavian13 5,192]

If I press B, nothing SHOULD happen, as what I did was a manual setting, as in real life.

 

This isn't true at all, actually. Pressure settings are given for the destination field, unless an ATC SOP specifies otherwise (in which case, they provide an intermediate station pressure, usually closer to where the aircraft will descend through TL).

 

Unless you're sitting on the ground at the destination field, the pressure around your aircraft may (and probably will) be different. That's a very important point to note. When ATC issues the altimeter setting, it's usually not the pressure around where you are, it's the pressure for the destination field, or some generic point reference to keep everyone at the same altitude within the controller's airspace.

 

Think of it this way:

If I have a large area to cover as a controller, I could have pressure settings that are different in different areas of the sector. As an example, there's a Potomac TRACON sector that covers SHD, CHO, 7W4, GVE and other airports. At this moment, each of those airports has an ASOS/AWOS reporting a different pressure:

KCHO 111753Z 12004KT 10SM FEW035 28/19 A3003 RMK AO2 SLP162 T02780189 10278 20189 58022

KSHD 111835Z AUTO 11003KT 10SM CLR 29/14 A3005 RMK AO2 T02850140

KGVE 111835Z AUTO 00000KT 10SM CLR 27/19 A3001 RMK AO1 T02690190

K7W4 111835Z AUTO 36003KT 10SM SCT013 SCT085 26/21 A3002 RMK AO1 T02590209

 

Which one is correct? Well, if you're flying into any one of them, the controller will ask/advise you of the weather for the specific field, but until you're close to that field (or if you're transiting the airspace), the controller is likely issuing altimeter settings off of CHO (the primary airport for that sector). With everyone on a single pressure altitude, there won't be much variation in altitudes if they get closer to each other (same reason why everyone uses the same altimeter settings above Transition Altitude).

 

All that being said, the idea that using the destination airport altimeter setting and then hitting 'B' and expecting it to not change is misguided. This is not a bug, and is more of a misunderstanding of weather concepts and ATC.

 

 

So, if settings are the same how can it work for 777 and NOT for 737??

 

Check your settings for the NGX - there are TCAS-related settings in the PMDG SETUP> menu structure. These are related to how the aircraft filters traffic on the display.

[rbgomes 0]

Thanks Kyle.

 

As for the altimeter, if I understand correctly your post, if I am indeed sitting on the ground connected to IVAO then if I press B then the QNH SHOULD be same as in the METAR, right?

 

If the answer is YES to the above question, then that is what I am talking about. On 737 and 777 they are NOT.

 

Example: I am just flying now from OITT to LTAC. METAR for OITT said QNH was Q1010 but to be on the correct field elevation, thus pressing B, the QNH went to Q1003. 

 

Imagine a CatII approach. QNH is extremely important... of course around me while on approach QNH should be variable, fully understood and known. But ON THE GROUND it should be as per METAR.

 

What is annoying is that QNH is JUST as METAR on other aircraft when online.

 

As for the settings... it will be highly appreciated if you could direct me exactly to where I must check the settings.

 

Thanks.

[scandinavian13 5,192]

As for the altimeter, if I understand correctly your post, if I am indeed sitting on the ground connected to IVAO then if I press B then the QNH SHOULD be same as in the METAR, right?

 

If the answer is YES to the above question, then that is what I am talking about. On 737 and 777 they are NOT.

 

If you're on the ground, yes, but see below for more.

 

Example: I am just flying now from OITT to LTAC. METAR for OITT said QNH was Q1010 but to be on the correct field elevation, thus pressing B, the QNH went to Q1003. 

 

Where were you when you were told QNH was 1010? Unless you're sitting at that location, what the pressure is when you press B is completely irrelevant (at least when it comes to trying to call something a bug). The only time it would be relevant (for troubleshooting purposes), is if you were sitting on the ground at the same exact airport where that pressure was reported.

 

 

 

Imagine a CatII approach. QNH is extremely important... of course around me while on approach QNH should be variable, fully understood and known. But ON THE GROUND it should be as per METAR.

 

...which is why the minimums are based on radio altimeter for such a sensitive approach.

 

On the ground, it should be per the AWOS/ASOS, and not necessarily the METAR, actually. If you go to a small airport, there's usually a computer terminal somewhere in the main terminal that has a screen showing the current weather conditions. At the bottom is the METAR. METARs are all well and good, but they're usually only taken once an hour. If a front passed through in that hour, the pressure could have changed quite rapidly.

 

If you're on the ground and there is a large discrepancy between a METAR and the sim, then you may want to have a look at whatever is downloading the weather (be it FSX, or IvAp). The 'B' shortcut is a sim function - you can use it in any flight sim aircraft, which means that if you're seeing an issue when in our planes, you're going to see the same with another plane.

 

 

 

What is annoying is that QNH is JUST as METAR on other aircraft when online.

 

Most likely because of how IvAp sources and downloads its weather.

 

 

 

As for the settings... it will be highly appreciated if you could direct me exactly to where I must check the settings.

 

FSX Settings, or the IvAp settings.

[rbgomes 0]

 

 

Where were you when you were told QNH was 1010? Unless you're sitting at that location, what the pressure is when you press B is completely irrelevant (at least when it comes to trying to call something a bug). The only time it would be relevant (for troubleshooting purposes), is if you were sitting on the ground at the same exact airport where that pressure was reported.
 

 

That is EXACTLY when this is happening: ON THE GROUND at the airport corresponding to the METAR. Other examples were so just for Steffan to understand. No ofense on saying this is a bug and likewise I will not be offended if the mistake is mine. The goal is not to set blame, but solve my problem. Thanks.

 

 

FSX Settings, or the IvAp settings.

 

 

See, maybe I should had posted 2 threads...

 

All works FINE with 777 on TCAS. It does not work with 737NX. How can the problem be with iVaP or FSX ?

 

Thanks.