Futuristic tools to increase the efficiency of the air traffic control system must deal with the increasing complexity of the aviation system due to a mixture of different aircraft types and business models, increased traffic volume, and varying aircraft performance. A comprehensive Metroplex planning system will help coordinate flights between the enroute and Metroplex domains, and manage surface traffic, using Next Generation Air Transportation System (NEXTGEN) concepts. To address this, IAI has been awarded a new contract entitled “METROSIM: Metroplex-Wide Flight Planning and Optimization.” MetroSim is a Metroplex-based arrival, departure, and surface optimization system that seamlessly links with NASA’s Traffic Management Advisor (TMA) and System Oriented Runway Management (SORM) tools. The MetroSim architecture contains a collection of different tools, including simulations, physics-based computations, and mathematical optimization calculations. These tools interoperate in a distributed computational environment to provide real-time airport planning and optimization at the Metroplex level for arrival, departure, and surface movement operations. MetroSim’s suite of highly interconnected and interacting tools can execute quickly on a variety of processors, and can exploit parallel processing through multicore computer architectures. Its distributed architecture is expandable, and is ideal for modern computer systems with multiple cores and Graphics Processor Units (GPUs). MetroSim builds on IAI’s experience in developing computer software for aviation systems, while including NextGen concepts like combined air/ground separation assurance, interval management, and dynamic wake vortex spacing, to help safely increase traffic density while reducing controller workload. MetroSim helps airport planners, traffic flow management experts, airline dispatchers, air traffic controllers and pilots to reduce the uncertainty in operations planning, recover quickly from disruptive events, maintain high throughput even in adverse weather conditions, and handle the uncertainties associated with weather forec.