Correspondence issued by the Government Accountability Office with an abstract that begins "The Federal Aviation Administration (FAA) is the lead implementer and planner for the Next Generation Air Transportation System (NextGen)--an ambitious, multiyear, multibillion-dollar overhaul of systems, procedures, aircraft performance capabilities, and supporting infrastructure that will create an air transportation system that uses satellite-based surveillance and navigation and network-centric operations. NextGen was designed as an interagency effort to leverage expertise and funding throughout the federal government. The Senior Policy Committee--the overall governing body for NextGen, chaired by the Secretary of Transportation--consists ocabinet-level officials from each of the partner agencies. The initial planning for NextGen, which began with Vision 100 in 2003 and was carried out by the Joint Planning and Development Office (JPDO) within FAA, focused on improvements to the air transportation system that would be implemented through 2025. JPDO produced three key planning documents--a Concept of Operations, a NextGen Enterprise Architecture, and an Integrated Work Plan (IWP). Recently, FAA has shifted its focus from the longer term (i.e., beyond 2018) and emphasized improvements that can be implemented in the near term and midterm (2010 through 2018). The shift responds, in part, to concerns expressed by stakeholders and Members of …

A letter report issued by the Government Accountability Office with an abstract that begins "The National Aeronautics and Space Administration (NASA) has long relied on the Delta II medium class launch vehicle to launch science missions. Delta II, however, is no longer in production, and no other vehicle in the relative cost and performance range is currently certified for NASA use. Thus, NASA faces a potential gap in the availability of medium class launch vehicles that could cause design challenges, delays, or funding issues. GAO was asked to assess (1) NASA's and the Delta II contractor's, steps to ensure resources (budget, workforce, and facilities) are available to support safe Delta II operations through the last planned NASA flight in 2011; (2) NASA's plans and contingencies for ensuring a smooth transition from current small and medium class launch vehicles to other launch vehicles for future science missions; (3) the risks associated with NASA's planned approach to fill the medium launch capability gap; and (4) technical and programmatic implications to science missions if NASA commits to new launch vehicles before they are certified and proven. GAO identified and assessed transition plans and mitigation activities and interviewed responsible NASA and government officials."