Recent advances in aircraft technology, including advanced collision avoidance and flight management systems, and new automated tools for air traffic controllers enable a shift from air traffic control to collaborative air traffic management. Free flight, a key component of air traffic management, will provide pilots with more flexibility, under certain conditions, to fly more direct routes from city to city. Currently, pilots primarily fly fixed routes—the aerial equivalent of the interstate highway system—that often are less direct because pilots are dependent on ground- based navigational aids. Through free flight, FAA hopes to increase the capacity, efficiency, and safety of our nation's airspace system to meet the growing demand for air transportation as well as enhance the controllers’ productivity. The aviation industry, especially the airlines, is seeking to shorten flight times and reduce fuel consumption. According to FAA’s preliminary estimates, the benefits to the flying public and the aviation industry could reach into the billions of dollars when the program is fully operational. In 1998, FAA and the aviation community agreed to a phased approach for implementing the free flight program, established a schedule for phase 1, and created a special program office to manage this phase. During phase 1, which FAA plans to complete by the end of calendar year 2002, the agency has been deploying five new technologies to a limited number of locations and measuring their benefits. Figure 1 shows how these five technologies—Surface Movement Advisor (SMA), User Request Evaluation Tool (URET), Traffic Management Advisor (TMA), Collaborative Decision Making (CDM), and passive Final Approach Spacing Tool (pFAST)—operate to help manage air traffic. According to FAA, SMA and CDM have been deployed at all phase 1 sites on or ahead of schedule. Table 1 shows FAA’s actual and planned deployment dates for URET, TMA, and pFAST. To measure whether the free flight tools will increase system capacity and efficiency, in phase 1, FAA has been collecting data for the year prior to deployment and initially planned to collect this information for the year after deployment before making a decision about moving forward. In December 1999, at the urging of the aviation community, FAA accelerated its funding request to enable it to complete the next phase of the free flight program by 2005—2 years ahead of schedule. During this second phase, FAA plans to deploy some of the tools at additional locations and colocate some of them at selected facilities. FAA also plans to conduct research on enhancements to these tools and incorporate them when they are sufficiently mature. FAA plans to make an investment decision in March 2002 about whether to proceed to phase 2. However, by that date, the last site for URET will have been operational for only 1 month, thus not allowing the agency to collect data for 1 year after deployment for that site before deciding to move forward. (See table 1.) FAA officials told us that because the preliminary data showed that the benefits were occurring more rapidly than anticipated, they believe it is unnecessary to wait for the results from the evaluation plan to make a decision about moving forward. To help airports achieve their maximum capacity for arrivals through free flight, FAA’s controllers will undergo a major cultural change in how they will manage the flow of air traffic over a fixed point (known as metering). Under the commonly used method, controllers use “distance” to meter aircraft. With the introduction of TMA, controllers will have to adapt to using “time” to meter aircraft. The major technical challenge with deploying the free flight tools is making URET work with FAA’s other air traffic control systems. While FAA does not think this challenge is insurmountable, we believe it is important for FAA to resolve this issue to fully realize URET's benefit of increasing controller productivity. Initially, controllers had expressed concern about how often they could rely on TMA to provide the data needed to effectively manage the flow of traffic. However, according to FAA and subsequent conversations with controllers, this problem was corrected in May 2001 when the agency upgraded TMA software and deployed the new version to all sites. To FAA’s credit, it has decided not to deploy pFAST to additional facilities in phase 2 because of technical difficulties associated with customizing the tool to meet the specific needs of each facility, designing other automated systems that are needed to make it work, and affordability considerations. Ensuring that URET is compatible with other major air traffic control systems is a crucial technical challenge because this requires FAA to integrate software changes among multiple systems. Among these systems are FAA’s HOST, Display System Replacement, and local communications networks. Compounding this challenge, FAA has been simultaneously upgrading these systems’ software to increase their capabilities. How well URET will work with these systems is unknown because FAA has yet to test this tool with them. FAA has developed the software needed for integration and has begun preliminary testing. Although problems have been uncovered during testing, FAA has indicated that these problems should not preclude URET’s continued deployment. By the end of August 2001, FAA expects to complete testing of URET’s initial software in conjunction with the agency’s other major air traffic control systems. FAA acknowledges that further testing might uncover the need for additional software modifications, which could increase costs above FAA’s current estimate for this tool’s software development and could cause the agency to defer capabilities planned for phase 1. Ensuring URET’s compatibility with other air traffic control systems is important to fully realize its benefits of increasing controllers’ productivity. URET is used in facilities that control air traffic at high altitudes and will help associate and lead controllers work together to safely separate aircraft. Traditionally, an associate controller has used the data on aircraft positions provided by the HOST computer and displayed on the Display System Replacement workstation to assess whether a potential conflict between aircraft exists. If so, an associate controller would annotate the paper flight strips containing information on their flights and forward these paper flight strips to the lead controller who would use the Display System Replacement workstation to enter flight plan amendments into the HOST. URET users we spoke with said that this traditional approach is a labor-intensive process, requiring over 30 keystrokes. With URET, an associate controller can rely on this tool to automatically search for potential conflicts between aircraft, which are then displayed. URET also helps an associate controller resolve a potential conflict by automatically calculating the implications of any change prior to amending the flight plan directly into the HOST. According to the users we spoke with, these amendments require only three keystrokes with URET. FAA, controllers, maintenance technicians, the aviation community, and other stakeholders agree on the importance of using a phased approach to implementing the free flight program. This approach allows FAA the opportunity to gradually deploy the new technologies at selected facilities and users to gain operational experience before total commitment to the free flight tools. It basically follows the “build a little, test a little, field a little” approach that we have endorsed on numerous occasions. To FAA’s credit, the agency has appropriately used this approach to determine that it will not deploy pFAST in phase 2. We also agree with major stakeholders that adapting to the program’s tools poses the greatest operational challenge because they will change the roles and responsibilities of the controllers and others involved in air traffic services. However, the success of free flight will rely on agencywide cultural changes, especially with controllers, who trust their own judgment more than some of FAA’s new technologies, particularly because the agency’s prior efforts to deploy them have had significant problems.Without training in these new tools, air traffic controllers would be hampered in fulfilling their new roles and responsibilities. Another major challenge is effectively communicating TMA’s capabilities to users. Because FAA has been deferring and changing capabilities, it has been difficult for controllers to know what to expect and when from this tool and for FAA to ensure that it provides all the capabilities that had been agreed when FAA approved the investment for phase 1. During our meetings with air traffic controllers and supervisors, their biggest concern was that the free flight tools would require cultural changes in the way they carry out their responsibilities. By increasing their dependence on automation for their decisionmaking, these tools are expected to help increase controllers’ productivity. Moreover, the tools will require changes in commonly recognized and accepted methods for managing traffic. Controllers and supervisors emphasized that URET will increase the responsibilities of the associate controllers in two important ways. First, their role would no longer be focused primarily on separating traffic by reading information on aircraft routes and altitudes from paper flight strips, calculating potential conflicts, and manually reconfiguring the strips in a tray to convey this information to a lead controller. With the URET software that automatically identifies potential conflicts up to 20 minutes in advance, associate controllers can be more productive because they will no longer have to perform these manual tasks. Second, they can assume a more strategic outlook by becoming more focused on improving the use of the airspace. URET enables them to be more responsive to a pilot’s request to amend a flight plan (such as to take advantage of favorable winds) because automation enables them to more quickly check for potential conflicts before granting a request. Although the controllers said they look forward to assuming this greater role and believe that URET will improve the operational efficiency of our nation’s airspace, they have some reservations. Achieving this operational efficiency comes with its own set of cultural and operational challenges. Culturally, controllers will have to reduce their dependency on paper flight strips as URET presents data electronically on a computer screen. According to the controllers we interviewed, this change will be very challenging, especially at facilities that handle large volumes of traffic, such as Chicago, because the two facilities that have received URET have taken several years to become proficient with it even though they have less traffic. Operationally, controllers said that URET’s design must include some backup capability because they foresee the tool becoming a critical component in future operations.