National Airspace System:

Problems Plaguing the Wide Area Augmentation System and FAA's Actions to Address Them

T-RCED-00-229: Published: Jun 29, 2000. Publicly Released: Jun 29, 2000.

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John H. Anderson, Jr
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Pursuant to a congressional request, GAO discussed the Federal Aviation Administration's (FAA) Wide Area Augmentation System (WAAS), focusing on: (1) difficulties in developing WAAS; (2) actions FAA is taking to get the system on track; and (3) next steps for FAA to take to help mitigate future delays in implementing WAAS.

GAO noted that: (1) FAA has underestimated the complexity of developing WAAS, which has led to cost increases and schedule delays; (2) in 1994, FAA estimated that it would cost $508 million to develop WAAS and promised to begin implementing the system by 1997; (3) the agency did not deliver on this promise, in part because of an aggressive schedule, which proved difficult to meet when the agency ran into problems in developing the WAAS design; (4) these problems led to the need for more software development; (5) FAA is again experiencing difficulties--mainly because of problems in meeting the system's key integrity requirement--that WAAS would virtually never fail to warn pilots of potentially hazardous misleading information; (6) GAO estimates that FAA will not deliver on its initial promises until 2003 and may incur additional costs of between $200 million to $240 million; (7) even though FAA's analyses have shown that quantified benefits of WAAS outweigh the costs, problems with the integrity requirement make this conclusion less certain; (8) to get the program back on track, FAA is taking a number of actions; (9) consistent with federal legislation related to information technology investments, FAA is taking a more incremental approach and in doing so is abandoning its high-risk approach of combining different phases of system development in an effort to more quickly implement systems; (10) FAA is also planning to develop checkpoints at which it will reevaluate WAAS development before making additional investments; (11) FAA is working more collaboratively with the aviation community--airlines, equipment manufacturers, and the Department of Defense--instead of making unilateral decisions about the WAAS design; (12) to address the integrity problem, FAA is participating in a team effort with its contractors and consultants to recommend solutions that will prove the system's integrity performance by the end of 2000; (13) while FAA's actions go a long way toward implementing WAAS, GAO believes that additional steps are necessary to ensure that FAA puts into place a framework to mitigate future delays and cost increases; (14) FAA will need to develop a comprehensive plan that incorporates the future checkpoints for the agency's investment in its new navigation system; (15) it will be critical for this plan to require FAA to revisit its investment if WAAS cannot perform as intended; and (16) to provide Congress with assurances that FAA has addressed these problems, GAO recommended that an external organization evaluate FAA's progress at established checkpoints.