Optimization based Tube Network Design for the Next Generation Air Transportation System (NextGen)

The skies over the US are becoming more crowded every day. The current airspace system is under growing strain as the demand for air travel is steadily increasing, from over 740 million passengers flying in fiscal year 2006 to an estimated 1 billion passengers by 2015, according to Federal Aviation Administration (FAA) estimates. The current national airspace structure consisting of ARTCCs, sectors, etc has been defined several decades ago and barely delivers optimum results in the current-day heavy and concentrated traffic scenario. There may be many ways to optimize the current structure but there is always the need of finding a new structure which would serve not only the current air traffic requirements but also the expected 3 fold increase in air traffic as predicted by the FAA by 2025. A tube network has been studied in this paper as a possible way to re-define the air routes structure taking into consideration the current air traffic scenario and future capabilites of aircraft to maintain autonomous separation. An optimum number of tubes required have been derived using the point to point operations data for the top 500 airports in the National Airspace System (NAS).