The capacity of the United States' National Airspace System (NAS) must double to handle the passenger demands that are projected over the next 25 years. NASA initiated the virtual airspace modeling and simulation (VAMS) project in 2002 with participants, including members from industry, government, and academia to develop and share ideas on revolutionary concepts to meet the future. The constraints in the terminal area domain are the focus of Raytheon's VAMS concept, terminal area capacity enhancement concept (TACEC). TACEC envisions a high level of automation and synchronization, generating optimized 4D flight profiles to land/depart multiple aircraft "simultaneously" on closely spaced parallel runways. Implementation requires infrastructure improvements such as high-speed data link, improved surveillance, integrated terminal area network, and highly automated guidance and scheduling systems. This paper focuses on the issues associated with the TACEC high-speed data link required to send flight profiles to the arrival and departing aircraft upon entering the terminal airspace. The minimum essential uplink/downlink parameters needed to support the optimized 4D flight profiles are defined. Issues such as data rate, traffic load, and feasibility are also examined.