ABSTRACT
This chapter addresses two broad types of Air Traffic Management (ATM) infrastructure investments. The first type comprises those aimed at increasing system capacity to handle aircraft movements in a given time period. In terms of investment appraisal, such ATM projects can be approached similarly to an airport investment aimed at increasing the aircraft movement capacity of its runway. The second type of project involves those aimed at improving the efficiency of flight procedures. This project type also has similarities with airport investments, namely those aimed at improving aircraft operations on the ground. The chapter addresses a project aimed exclusively at improving flight efficiency, with no implications for capacity. The impact of air pollutants and noise on en route sectors is debatable. Therefore the treatment of environmental impact focuses on greater greenhouse gas (GHG) emissions. The use of larger aircraft will reduce GHG emissions per passenger.
