To change your default FOV you will have to open the clientprefs.cs file found in your gamedata/base/prefs directory. Find the entry called $pref::Player::defaultFov and edit the value so that it is to your liking. Example, $pref::Player::defaultFov = 120 will change your FOV to 120. Note: Some versions of Tribes2 have a bug which means that the default FOV will only be set after zooming, simply press your zoom key after respawning.

If you just wish to experiment with different FOVs without needing to exit or restart the game then enter setdefaultFOV("FOVValue"); at the console. Example, setdefaultFOV("120"); will allow you view the gameworld with a 120 FOV. You can access the console by pressing the key below ESC or the key you have bound to console.