Its for 'online' only with no missions - you have to pick the airfield you spawn from, and so will not work in FMB; unless you know how to do stuff with FMB, it's purely for air racing, scenic flying/testing or PvP I think.
My air racing maps are in online/Dogfight 1/AirRacing, which you can practise offline by creating a host even if the net is uplugged...