The use of satellites for air traffic management purposes offers many benefits for the future aeronautical communications infrastructure. Satellites can provide seamless and nearly global coverage over land masses, oceans, and remote areas with a reduced terrestrial infrastructure. Research and Development for a new satellite based air-ground data link has been endorsed by the EU Transport Council. It is widely shared among stakeholders that use of this satellite link in dense continental airspace requires new performance standards, which calls for a new ATMdedicated satellite communication standard and the supporting satellite capacity. This paper provides a characterization of the future data communication traffic profile and derives initial bandwidth estimation for a satellite system providing the service in the ECAC region.