Federal Aviation Administration, Washington DCSince the STS-114 mission in August of 2005, the FAA has partnered with NASA to protect aircraft flying in the National Airspace System from the potential hazards associated with a catastrophic failure of a reentering Space Shuttle orbiter, similar to that which occurred during STS-107 in February of 2003. This work has produced a set of procedures and tools for use before and during the reentry to provide FAA air traffic managers and controllers with increased situational awareness. An initial approach was implemented for STS-114 based on the need to maximize the time for the FAA to react to an orbiter failure. This approach has evolved over time through the identification of lessons learned on subsequent flights and the subsequent development of additional requirements to address them. This includes the development of the Shuttle Hazard Area to Aircraft Calculator (SHAAC), a dedicated tool for use in both reentry planning and real-time modes. This paper describes some of those key lessons and the approaches taken to address them. Emphasis is placed on those lessons that resulted from specific air traffic management needs. Many of the lessons learned to date have been captured as requirements for a next-generation FAA tool that will provide similar capabilities during the planning and operational phases of the launches and reentries of future commercial space vehicles. Future commercial space operators and air traffic managers in other organizations may find these lessons useful in the development of future tools to support their space and air traffic safety needs.I. Introduction N the spring of 2005, the Federal Aviation Administration (FAA) began investigating the use of existing air traffic tools to establish Temporary Flight Restrictions (TFRs) for protecting aircraft from the potential hazards of a NASA Space Shuttle orbiter failure during the planned reentry of the "Return to Flight" (STS-114) mission. This work was initiated from a recommendation of the Columbia Accident Investigation Board (CAIB), which highlighted the potential risks to aircraft from the hazards of falling spacecraft debris using data from a study of the Space Shuttle Columbia (STS-107) accident 1 . Although a number of procedures for FAA support of Shuttle operations were in existence prior to this accident, these procedures did not take into account the potential hazards to aircraft of falling Shuttle debris during a planned reentry.In the process of this investigation, several approaches to airspace management were considered. Each approach relied on the same key capabilities in its formulation: the ability to accurately model a Shuttle reentry accident, the ability to identify the potentially affected airspace, and the ability to assess the potential impacts on the air traffic in the National Airspace System (NAS). This paper describes the new tools that were developed and the existing tools that were modified to provide FAA air traffic managers with these capabilities. The method by wh...