This effort supports NASA Recovery Act work sponsored by the Aeronautics Research Mission Directorate and the Airspace Systems Program. Research funded by this work will focus on addressing the capacity challenges facing the US national airspace. It is forecast that over the next 15 years, air traffic in the United States will double, far exceeding the country?s current capability to safely fly aircraft. To handle this growth, NASA is contributing toward the development of the Next Generation Air Transportation Management System (NextGen). In support of these efforts, the contractor shall develop a candidate airspace configuration that describes procedures and routes for airplanes arriving to and departing from a major Metroplex in the United States with heavy aircraft traffic: the Southern California TRACON. The planned milestone for this task is a presentation of the airspace definition created for Southern California metroplex comprising six subject airports: Los Angeles International (LAX), Burbank/Bob Hope (BUR), Ontario International (ONT), Long Beach (Daugherty Field) (LGB), Santa Ana/John Wayne Airport-Orange County (SNA), and San Diego International (SAN). The completion criterion is 100% of the task within 8 months of the contract award. Deliverables are airspace definitions which shall include arrival and departure routes and procedures for each subject airport that consider traffic from the other subject airports.