Allow reading environment SimVars from non-aircraft SimObjects

We would like to be able to read environment variables (e.g. ambient
temperature, precipitation rate & type, baro pressure, wind
velocity/direction, etc.) from a SimObject we create ourselves via SimConnect
that is not the user aircraft (e.g. ground service vehicle or non-aircraft
entity), however, it seems as though these variables cannot be read for
simobjects that are not aircraft. Is it possible to allow these environment
simvars to be read by developer-created SimObjects? thanks!

Hello @IcemanFBW The reason why we are not able
to return weather data for SimObjects is the same reason why we don’t have a
Weather API to request weather data at a position defined by the user anywhere
in the world. The weather simulation runs only at the ownship position and
that is the only position where we can return accurate weather information
plus a small radius around the aircraft when needed. So this technically not
feasible as we speak and not a formality to do. Can you give us a few examples
of how you would use this information so that we can better estimate how
useful it could be? Regards, Sylvain

Hi @FlyingRaccoon, Having the possibility to
read these environmental variables on a non-user SimObject would allow us to
develop sensors/ probes and obtain a volumetric beam in front of the aircraft
that could be used as a detailed weather radar. The radius we would need would
be around 700nm with a 40/45 degree aperture right in front of the aircraft.
This was one of the technics used in the old FSX days and would be very
helpful. Thank you. Best,

SimConnect was designed to interact with aircraft, the SimVars variables
originate from that system. But there exists a [wind
attribute](https://www.fsdeveloper.com/forum/threads/flag-waving-in-the-wind-
direction.449666/#post-860935) in animation-tags for objects, and several
preset animations are available for wind. You could connect your geometry to a
wind sock object ? I doubt if general access to “SimVars” can be done. You
don’t “run” your object, MSFS will…

This is useful for functions such as predictive windshear. Without a new API
to check weather around the aircraft there aren’t any good options.

I would like to make the lifetime of contrails for AI traffic dependent of
humidity for instance. This is from an aircraft object though, but not
possible as far as I know.

Maybe I have misunderstood you; if so my apologies. But this argument is not
completely correct. Not sure what SimConnect was designed for initially, but I
can tell you that since the times of FS2004/FSX we are able to interact with
other SimObjects and the environment, not just aircraft or the user aircraft.
General access to certain SimVars could be done; for example, I can obtain
lat, long and altitude of a distant SimObject. That of course doesn’t mean we
can access all of them, but it’d be worth a try. As the topic suggests, we
need some way to obtain environmental data at a given position to predict
windshear, and display a realistic weather radar. Without it, any attempt to
have a weather radar will be useless.