VoxATC Roller coaster

[503Kento 11]

Recently made and IFR flight from 2O1 in Quincy, CA to KFMR Rogue Valley International - Medford, OR.  Using Little Navmaps recommendation to clear all the mountains my planned altitude wa 8K ft.  Shortly after takeoff, Vox told me to clime to 10k, then a couple of minutes later 12k, 14k, 16k them back to 10k up and down and up and down. Flying the a2a Comanche, I cant climb as quickly as Vox wanted me too.  Plus, I think IRL, one would need oxygen above 10k.  The climb and descend instructions did not stop until I entered the rogue valley and was out of the mountains.

Is this some sort of terrain avoidance functionality?

Is there some way to tell Vox the capabilities of my AC I.e no O2 so that I’m not asked to do things I cannot accomplish?

[RancidViper 37]

I have the exact same issue when flying around mountains. Not sure if there is any way to tweak it. Hopefully someone else can shed some light on it.

[jabloomf1230 2,445]

Unfortunately, VOXATC will follow the proscribed altitudes in your flight plan except when safe minimums over terrain are exceeded. One can turn off the terrain-sensing option by editing a setting in the main configuration file.  But then you may get vectored into a mountain. 

The herky-jerky nature of the instructions has to do with the coarseness of the online dataset that is used by VOXATC to determine altitude AGL. 

[RancidViper 37]

1 hour ago, jabloomf1230 said:

Unfortunately, VOXATC will follow the proscribed altitudes in your flight plan except when safe minimums over terrain are exceeded. One can turn off the terrain-sensing option by editing a setting in the main configuration file.  But then you may get vectored into a mountain. 

The herky-jerky nature of the instructions has to do with the coarseness of the online dataset that is used by VOXATC to determine altitude AGL. 

Hi Jabloom,

Would you happen to know what that safe minimum distance might be? That way it maybe possible to edit the flight plan itself to either re route or cruise at a higher altitude.

Cheers

[jabloomf1230 2,445]

I'm away from my flightsim PC until this weekend so I can't check what it is exactly. There are regulatory inconsistencies among countries  with regard to minimum safe AGL altitudes. The factors influencing this include whether instrument conditions apply, whether the aircraft is on an airway and whether the flight plan traverses mountainous areas. That makes me wonder whether VOXATC just uses an arbitrary minimum altitude like either 2,000 or 2,500 feet AGL.

[RancidViper 37]

2 hours ago, jabloomf1230 said:

I'm away from my flightsim PC until this weekend so I can't check what it is exactly. There are regulatory inconsistencies among countries  with regard to minimum safe AGL altitudes. The factors influencing this include whether instrument conditions apply, whether the aircraft is on an airway and whether the flight plan traverses mountainous areas. That makes me wonder whether VOXATC just uses an arbitrary minimum altitude like either 2,000 or 2,500 feet AGL.

That's also what I was thinking. I doubt it has a database of all the different regulations etc. So I assume that it's just using some hard coded value. In which case we could either try and edit that value or work around it by filing flight plans at higher altitudes and/or navigating around terrain.

Because as the OP suggested, it's quite annoying when I am in IMC conditions and trying hard to keep the airplane flying straight and level, then the controller tells me to climb a couple thousand feet, and then before I get halfway there I get told to descend back to the original altitude. And this repeats over and over until you're away from terrain.

Sometimes I just ignore them and they eventually give up.. But that's not a good way to practice is it?

Edited April 5, 2018 by RancidViper

[503Kento 11]

Thanks for the insights guys.  Valuable to know I’m not the only one experiencing this phenomenon. 

[jabloomf1230 2,445]

Every other ATC app may vector you into the ground in mountainous terrain. V7 is the first VOXATC version that at least attempts to do something about that. I would assume that some improvements might be expected. Other than disabling the terrain avoidance option the only other solution to to file a much higher flight plan.

[503Kento 11]

Yep, I am planning on repeating the flight at a higher altitude and see what happens. Donning my oxygen mask of course 

[jabloomf1230 2,445]

😃 I first noticed this when I tried flying IFR across Vancouver Island, BC from Tofino to Nanaimo. I kept getting instructions to climb to 8000 then descend to 7000. Filing a higher cruise  altitude fixed it and I sent my bill for the excess fuel to Internal Workings.

 

[Mad_Mac 21]

On 4/4/2018 at 8:26 PM, 503Kento said:

Recently made and IFR flight from 2O1 in Quincy, CA to KFMR Rogue Valley International - Medford, OR.  Using Little Navmaps recommendation to clear all the mountains my planned altitude wa 8K ft.  Shortly after takeoff, Vox told me to clime to 10k, then a couple of minutes later 12k, 14k, 16k them back to 10k up and down and up and down. Flying the a2a Comanche, I cant climb as quickly as Vox wanted me too.  Plus, I think IRL, one would need oxygen above 10k.  The climb and descend instructions did not stop until I entered the rogue valley and was out of the mountains.

Is this some sort of terrain avoidance functionality?

Is there some way to tell Vox the capabilities of my AC I.e no O2 so that I’m not asked to do things I cannot accomplish?

A2A simulates blackout. If you fly the Comanche above 12,000 feet for extended periods you will get to experience it. If you get under 10,000 quickly enough (without meeting terrain) you can even recover and not die. 

[503Kento 11]

Jay, I assume you are still awaiting payment ;)

Mad Mac, ohhh blackout simulation, that should be interesting. Thanks for the information. I’ll,let you know how it goes...assuming I don’t die. ;)