Requirements for air traffic management in the en-route environment

Future aviation traffic is expected to continue to increase at 2% or more annually for the foreseeable future, unless the aviation system capacity acts to constrain this growth. To remove long-term airspace capacity limitations, new methods of air traffic management must be implemented. These new methods will necessarily require significant increases in the flow of information between air traffic management entities both on the ground and in the air. To support increased information flow, new aviation communications architectures are being investigated. One architecture gaining advocacy uses satellite communications for aircraft-ground and aircraft-aircraft communications while aircraft are flying in the en-route phase of flight. The purpose of this paper is to investigate the communications requirements for the en-route part of such an architecture. In particular, we will derive the instantaneous aircraft volume in the en-route environment by examining current air traffic statistics, as well as projections for future traffic. We also analyze the volume of data flow that might occur between aircraft in the en-route environment and air traffic management entities on the ground and examine the implications of these results on the design of satellite communications links that would serve the en-route communications requirements in the future.