Just started working offshore a few months ago. Its scary how accurate the GPS are today. If you are at the same altitude and on the same route in opposit directions, it seems that a mid air would most likely occur. The tcas we use is not accurate at all. It can see the traffic if its above OR below. But not when you are at same altitude. Collegue told me that Eurocopter have tryed to fix it but cant find a solution.