Gentlemen,I am in collaboration w/ another gentleman making a replacement panel for the ALPHA F-111 Aardvark, the freeware project is going very nicely in as much as the the end user may have to refer to the "dash-1" manual for autopilot use. :-)Ref - https://sites.google.../shess0757/homeThe one little problem we are having is in the "Terrain Following" mode of the autopilot as it references ground elevation directly below the aircraft. We do have a working TF mode that works very well as long as the speed is low enough (~400 kts) and there is some kind of upslope prior to the peak. Did tests via the GPS system, aircraft.cfg datum reference etc to get a ground elevation at a given lat/lon or distance ahead.. None of them work.. There is a workaround, given, -Can XML (L:Vars) intercommunicate w/ C++ ? ( Standard FS vars = YES, L:Vars = ? via ExecuteCalculatorCode? )Can a C++ gauge/module intercommunicate w/ SimConnect ?If both are yes then the workaround another gentleman (Ian Foster-Lewis, callsign - b21) made should work, C source available. Given a certain Lat/Lon, invisible AI item(s) can be spawned via SimConnect into FS for a very short time (< 0.5 sec) and the ground altitude can then be read. This gentleman did some extraordinary things in this same fashion to provide dynamic up/down-draft lift for soaring pilots. Very cool! :-)Ref - http://carrier.csi.c.../dev/sim_probe/ (Source at this location)Ref - http://carrier.csi.c...robe_paper.html (White Paper)Ref - http://forum.avsim.n...via-simconnect/ Dec2007Now, if the above questions are both yes.. Would a C programmer like to give this a go? It would be a highly shaved down version of b21's source. On the XML side of things we would calculate the requested spawn(s) lat/lons via the GPS GeoCalc functions using airspeed, delta heading rate, heading, current lat/lon. On the C side ( if available ) it would send to SimConnect the spawn commands (create/delete etc..), lat/lon(s), etc.., retrieve the ground altitude(s), then send them back to XML..Thank-You in advance for any insight.Happy Holidays,RomanP.S. This may have gone into the SimConnect forum, but it has already been answered that XML cannot be read/written "directly" from SimConnect. A C gauge guru probably has more information necessary.

What you're suggesting is completely possible.The only serious issue that I can think of will be frame rates, particularly in a multi-player situation.Doug