Landing VATSIM traffic anomaly

[Xander Koote 0]

Hello,

not sure where to report this as I don't know where the problem lies yet. Since the last 3 or 4 months now I have noticed that ALL online traffic around me have this weird behavior when landing. AT around 50' above the runway, the model slams down to runway elevation and immediately back up to where the airplane actually is. The rest continues normally.

Has anyone noticed this? Any idea where to start troubleshooting?

[Ross Carlson 156]

Which sim are you using?

[Xander Koote 0]

I am using P3Dv5. Mate of mine I regularly fly online way, and a popular British Twitch streamer have the same thing.

Normal Approach

- 50 feet

- Instantly on ground (with landing smoke)

- Instantly back to it's original height

- Onwards to the traffic's landing (with second smoke at the traffic's true T/D)

[Ross Carlson 156]

Nothing has changed with respect to how vPilot handles "ground clamping" which is the process of smoothing out the differences in terrain elevation between different sims, or different scenery packages. The only thing that has changed recently is the introduction of MSFS. Do you happen to know which sim the other pilots are using? You said that ALL other aircraft exhibit this behavior, but I'm wondering if maybe it's only other aircraft coming from MSFS.

[Xander Koote 0]

For me it is P3D v5 and as well for the streamer. Which of course doesn't answer your question. The only time I am sure is when we fly together. We both use P3Dv5. And every time I stop to see him land, I see the behavior.

[Ashwant Gonesh 1]

Hi, 
I can confirm that I also see this issue happening on my end. I (also) fly P3Dv5.1. 
With the person I fly with, I use an edited custom .vmr file (linking to aircraft liveries in my SIM). Could this be a culprit? But then, it never used to be...as I use this edited .vmr since P3Dv4.5 HF2.

[Ross Carlson 156]

Okay, thanks for the info. I haven't seen this myself, so it'll be hard for me to troubleshoot, but I'll look into it when I get the chance.

[Andreas Fuchs 239]

Maybe you can provide an URL to one of the stream videos where it has happened recently.

[Ross Carlson 156]

19 minutes ago, Andreas Fuchs said:

Maybe you can provide an URL to one of the stream videos where it has happened recently.

I understand from the description what's happening. I will need to be able to reproduce it myself so I can inspect the actual values coming in over the network before I'll be able to resolve it. A video won't add anything unfortunately.

[Xander Koote 0]

Thanks in advance Ross....

[Andreas Fuchs 239]

41 minutes ago, Ross Carlson said:

A video won't add anything unfortunately.

Fair enough, maybe a look at such an even would have sparked an idea of what could be the reason. I recently opened a support ticket with another developer and they were really thankful for seeing the described issue in action.

[Ross Carlson 156]

3 minutes ago, Andreas Fuchs said:

Fair enough, maybe a look at such an even would have sparked an idea of what could be the reason. I recently opened a support ticket with another developer and they were really thankful for seeing the described issue in action.

Normally that's the case, but not here unfortunately. The description of the issue tells me that it's definitely a ground clamping problem, and a video would only confirm that. The only way a video would change anything is if the OP's description is completely incorrect and it's not actually a ground clamping problem. 

5 hours ago, Xander Koote said:

Since the last 3 or 4 months

Xander, did anything change in your system 3 or 4 months ago, such as installing a global terrain update, anything like that?

[Xander Koote 0]

Ross,

the only thing I installed more or less in that timeframe was ORBX Global Vector. P3Dv5. Which doesn’t change elevation I believe. I could backup and delete my scenery indexes and go stand in the corner of a busy airport to see if it’s related to scenery add-ons. Do you think that would help?

[Koen Meier 14]

3 hours ago, Xander Koote said:

Ross,

the only thing I installed more or less in that timeframe was ORBX Global Vector. P3Dv5. Which doesn’t change elevation I believe. I could backup and delete my scenery indexes and go stand in the corner of a busy airport to see if it’s related to scenery add-ons. Do you think that would help?

Yup orbx vector for p3d v5 has no elevation correction anymore due to v5 having updated world data for elevation.

[Ross Carlson 156]

10 hours ago, Xander Koote said:

Ross,

the only thing I installed more or less in that timeframe was ORBX Global Vector. P3Dv5. Which doesn’t change elevation I believe. I could backup and delete my scenery indexes and go stand in the corner of a busy airport to see if it’s related to scenery add-ons. Do you think that would help?

The last time I made any changes to the ground clamping code was with version 2.6.0. If you're willing, please try installing the version just prior to that, which 2.5.2, and see if the problem occurs. Here is the installer:

https://vpilot.metacraft.com/Assets/Files/Installers/vPilot-Setup-2.5.2.exe

You don't need to uninstall your current version first, the 2.5.2 installer will overwrite it.

[Xander Koote 0]

I will try that and see Ross. I’ll pop back in when I do. Thanks 👍🏼

[Ross Carlson 156]

On 12/18/2020 at 2:42 PM, Xander Koote said:

I will try that and see Ross. I’ll pop back in when I do. Thanks 👍🏼

Xander, did you ever get a chance to try 2.5.2?

[Xander Koote 0]

Hey Ross,

no. Not yet. I’ve been having way too much fun on VATSIM these days to go bug hunting 🤣. I also wanted to make sure it still happens. It still does, but now after paying special attention it seems less so. But I will try it out this month and report back before the end of the month. 

[Ross Carlson 156]

No worries ... I appreciate any help you can find the time for. 

Edited January 17 by Ross Carlson