Arrival ATIS ......

[vadriver 247]

Team

There are many previous topics about issues with the titled, mostly about inaccuracies / differences from the sims's and / or the weather engine.

Solutions suggested (apart from a "fix") include re-enable of Vox to "update" the weather "correctly".

& yes I have been chasing the "issue" trying to understand if there's a "workaround" ..... but to no avail (apart from the disable / enable just before TOD / STAR transition & an expected arrival clearance).

However, on my most recent I stumbled on a curious coincidence if that's the best expression.

On the flight KSLC to KSFO, departure ATIS was spot on (a 10kt southeasterly) ... & then approaching the STAR (no re-enable), received an arrival clearance the opposite to what I expected (an arrival to the 19's rather than a 28's landing). I checked ASP4's destination weather to be that westerly wind expected from the TAF but also looked at the current weather at the departure to read it had been updated though was still similar to the time of departure (slight wind / altimeter / temp change).

Shortly after, I checked the VOX ATIS (the KSFO ATIS freq / on comm 2 at about 40nm from SFO) & would you believe it was calling the current departure's weather, not the destination's & thus it seems why the clearance was not to the 28's.

A fatal error soon thereafter occurred ... and after a re-enable, correct weather was received & vectors to 28's received.

So for now, I'll keep an eye on this "coincidence" ....... the weather does update but it is jammed on the departure !!

Any similar experiences / observations would be interesting to hear.

[jabloomf1230 2,445]

The handling of METAR data in P3d4 can be quite confusing and the answer to your question is probably only known to Tegwyn West, the developer of VOXATC. But let me babble on a bit on what I remember reading about weather in VOXATC. As I recall, VOXATC 7 does not read the ASP4 weather snapshot file, usually located at:

C:\Users\<USERNAME>)\AppData\Roaming\HiFi\AS_P3Dv4\Weather\current wx_snapshot.txt

That means it either uses either SimConnect or FSUIPC (since VOXATC definitely does not use the P3d4 PDK) to read the weather from the sim (which is generated by ASP4) and again as I recall, it uses FSUIPC to do so. It is possible to both log the FSUIPC weather data and to display one variable in the sim's title bar. I display barometric pressure (offset=0EC6), but in the past, I've displayed other variables just to see what was happening at the aircraft position. There are a few configuration variables contained in FSUIPC5.ini that impact how FSUIPC handles weather data, but this topic is best left to the FSUIPC manual to explain. In any case, I've noticed some small deviations between what ASP4 says the weather is and what VOXATC and FSUIPC say the weather is. I have no idea why this is true, but one way of cutting down on this possibility is to download ASP4 weather at a longer interval. Another way is to check the ASP4 option "Force ATC wind lock". A third possibility is to check the ASP4 option "Prevent downloads on approach".

Edited February 14, 2019 by jabloomf1230

[Mad_Mac 21]

13 hours ago, vadriver said:

 

A fatal error soon thereafter occurred ... and after a re-enable, correct weather was received & vectors to 28's received.

This suggests another possible “fix” when receiving weather inconsistencies. Just reboot VoxATC. Checking with ATIS outside of controlled airspace (as one would do in real life) would allow plenty of time for this. 

[vadriver 247]

Team

An update you might say on this topic ....... more so given some weird & wonderful arrival / approach "discrepancies" on recent flights (3-4hr flights between for example VHHH & RJBB) using historical ASP4 weather.

Essentially specific runway STAR assignment at over 100nm from the destination I have concluded was based on departure winds and subsequently at about 30nm, approach clearance was the opposite runway (& thus not anyway connected to the arrival flown)..... Vox ATIS at that time was appropriate & matched both the sim's and ASP4 metar.

The Vox  ATIS at TOD (theoretically it should not be heard) was describing updated departure weather as best i could judge.

So fundamentally, this is as I posted above a few months ago. Where it is more  exacerbating is when (as is often the case at a lot of Asian airports is that small fluctuations in afternoon north-westerlies on NE/SW runways can alter the assignment... mostly as a wind swing of 20o with little change in runway wind changes the assigned AI / runway use according to the sim's "scoring" of such.

On 2/14/2019 at 3:08 PM, jabloomf1230 said:

That means it either uses either SimConnect or FSUIPC (since VOXATC definitely does not use the P3d4 PDK) to read the weather from the sim (which is generated by ASP4) and again as I recall, it uses FSUIPC to do so.

I agree with your note Jay. I would though add that TJ has been quoted elsewhere as advising that Vox only reads the destination weather at 30nm well after STAR assignment ...... though with ASP4 it can only be read a tad earlier anyway.

So i forge on trying as best I can to be prepared for what may happen ..... unfortunately such options as ASP4's "prevent downloads on approach" are limited to that 60nm also.

At best, I can only hope TJ would "recognise" (despite a few glitches with V742's ATC part) the opportunity given the current capabilities of Vox's AI control, he might be able to tweak it to for example "stop" Vox changing runways (ie different to the STAR's runway) if the runway wind is still < a 10kt tailwind.

Even more so, if he could tweak Vox to read a "30 minute ahead" metar (as would be possible with ASP4's historical mode) rather than the injected at TOD, that would be almost the ideal ..... I would still be asking for a tweak to only use certain runways for certain times of the day (if tailwind is <10kt).

Yours in hope  😉