The Rotors Air Taxi work differently from a conventional Taxi. With a helicopter you can travel to any area, even if you have never been there before. Best of all, they can airlift you from your current map!
Simply open up your world map (default key: M) and move your mouse-cursor to your desired location, be it visited or unexplored. Locate and click on the Rotors Air Taxi to prompt confirmation for your travel.
If you are trying to travel to location that you have previously visited, you will be charged Mesos. However, if you are traveling to an unexplored location then you will need to use Rotors Walkie-Talkies to travel to that destination.
With Premium Club Membership, the Rotors Air Taxi can be used freely.