Aircraft Visibility Range and How to Set It
To set the range at which other aircraft become visible it is necessaye to run the IvAp Configuration executable.
This is located in the IVAO folder e.g. C:\Program Files (x86)\IVAO\IvAp v2
Run the executable and use the slider to set the Visibility Range: (the default is 10 Nm).
Add-ons menu... FSCopilot... Inn Control Panel
The CONTROL PANEL will load first then click SET to load the other panel. Under General... Multiplayer the range at which other aircraft become visible can be set. The default is 150 Nm which is extreme as in 'real world' it would be much less than this. Reducing this figure to a more realistic figure of 20 Nm or less may also help with frame rates.
If you are also using the excellent Freeware Program Plan-G from TaSoftware the multiplayer range can also be set.