The work under this research deals with the development of a computational framework suitable for the design and analysis of 4D green trajectories for terminal airspace operations. First, a 4D-trajectory-based operational concept for terminal area operation consisting of ground-side automation and flight-deck-side automation is presented. The focus of the current paper is the development of 4D-trajectory design tools as part of the ground-side automation. The paper first identifies aircraft aerodynamic, fuel consumption, emissions, and noise models necessary for trajectory optimization based on open-source data such as the Base of Aircraft DAta (BADA). A numerical trajectory optimization framework is then proposed for the design of 4D-trajectories. The framework is able to accommodate aircraft performance constraints, separation constraints, and airport capacity considerations, and it can model "green" considerations such as fuel & emissions minimization, and noise reduction. The trajectory optimization framework is demonstrated on single and multiple aircraft scenarios. Using parametric optimization approach the paper explores the relationship between the time-of-arrival at runway threshold and the fuel consumption for a B737 aircraft. In the multi-aircraft scenario the paper illustrates the implementation of 3 nmi separation criteria between a pair of aircraft. A companion paper deals with the flight-deck-side automation that tracks the 4D trajectory clearances created by the groundside automation.Automation concepts for NextGen terminal area operations can be categorized as (i) ground-side automation systems, or (ii) flight-deck-side automation systems. The research in the current paper is focused on ground-side automation. Reference 6 describes a concept for future high-density terminal air traffic operations that has been developed by the Airspace Super Density Operations (ASDO) researchers at NASA Ames Research Center. The concept described in Reference 6 includes five core capabilities: 1) Extended Terminal Area Routing, 2) Precision Scheduling Along Routes, 3) Merging and Spacing, 4) Tactical Separation, and 5) Off-Nominal Recovery. The first two capabilities are strategic planning tools and the remaining three are tactical decision support tools. In general tools developed for ground-side operations could be classified as (i) Stategic Planning Tools, and (ii) Tactical Decision Support Tools. The following sub-sections describe the past research under these two categories.
A. Strategic Planning ToolsStrategic planning tools deal with (i) route and runway assignment, and (ii) scheduling and sequencing at key points such as the meter fix and the runway threshold. The Traffic Management Advisor (TMA) 7 is one of earliest scheduling tools developed at NASA Ames Research Center. The TMA supports en route controllers and managers with scheduling, spacing, and arrival flow management and is currently deployed at multiple Air Route Traffic Control Centers. The TMA uses a timeline graphical user interface (TGUI) t...