Air Traffic Control:

Complete and Enforced Architecture Needed for FAA Systems Modernization

AIMD-97-30: Published: Feb 3, 1997. Publicly Released: Feb 3, 1997.

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Linda D. Koontz
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GAO reviewed the Federal Aviation Administration's (FAA) air traffic control (ATC) modernization effort, focusing on: (1) whether FAA has a target architecture and associated subarchitectures, to guide the development and evolution of its ATC systems; and (2) what, if any, architectural incompatibilities exist among ATC systems and the effect of these incompatibilities.

GAO found that: (1) FAA lacks a complete systems architecture, or overall blueprint, to guide and constrain the development and maintenance of the many interrelated systems comprising its ATC infrastructure; (2) FAA is developing one of the two principal components of a complete systems architecture, the "logical" description of FAA's current and future concept of ATC operations as well as descriptions of the ATC business functions to be performed, the associated systems to be used, and the information flows among systems; (3) however, FAA is not developing, nor does it have plans to develop, the second essential component, the ATC-wide "technical" description which defines all required information technology and telecommunications standards and critical ATC systems' technical characteristics; (4) the lack of a complete and enforced systems architecture has permitted incompatibilities among existing ATC systems and will continue to do so for future systems; (5) overcoming these incompatibilities means "higher than need be" system development, integration, and maintenance costs, and reduced overall systems performance; (6) because there are no standards for programming languages or open systems, ATC systems' software has been written in many different application programming languages, often exhibiting proprietary system characteristics; (7) this not only increases software maintenance costs but also effectively precludes sharing software components among systems; (8) without a technical architecture specifying the information technology standards and rules, the opportunity to share software will likely be lost; (9) in some cases, system incompatibilities exist because the technology and standards now available to permit system integration and interoperability did not exist or were only emerging when the systems were designed and developed; (10) other system incompatibilities are the result of FAA's failure to adopt and effectively enforce a technical architecture; (11) by failing to formulate a complete systems architecture, FAA permits and perpetuates inconsistency and incompatibility; (12) as a result, future ATC system development and maintenance will continue to be more difficult and costly than it need be and system performance will continue to be suboptimal; (13) FAA's management structure for developing, maintaining, and enforcing an ATC systems architecture is not effective; and (14) instead, processes now in place permit the acquisition of architecturally non-compliant systems without special waiver of architectural standards.

Recommendations for Executive Action

  1. Status: Closed - Implemented

    Comments: FAA has a logical systems architecture, but--after more than four years of effort--has not yet completed its technical architecture. FAA has made significant progress in developing technical architecture service areas--separation assurance, traffic synchronization, navigation, and flight planning, but an FAA systems architecture official stated that a complete technical architecture document will not be available until the end of 2002. Further, this official stated that the technical architecture will not determine the architectural components for the Host Computer System replacement; the winning contractor will be responsible for doing so.

    Recommendation: The Secretary of Transportation should direct the Administrator, FAA, to ensure that a complete ATC systems architecture is developed and enforced expeditiously and before deciding on the architectural characteristics for replacing the Host Computer System.

    Agency Affected: Department of Transportation

  2. Status: Closed - Implemented

    Comments: Two different entities share responsibilities for FAA's systems architecture. FAA's Acquisition and Research (ARA) organization is responsible for developing and maintaining the National Airspace System (NAS) systems architecture. FAA's investment management council has the budgetary and organizational authority to enforce the systems architecture. FAA's investment management policies require agency officials to consider whether a potential system is compatible with the systems architecture before making a decision to acquire the system.

    Recommendation: The Secretary of Transportation should direct the Administrator, FAA, to establish an effective management structure for developing, maintaining, enforcing the complete ATC systems architecture. Specifically, the Administrator should: (1) assign the responsibility and accountability needed to develop, maintain, and enforce a constrained ATC systems architecture to a single FAA organizational entity; (2) provide this single entity with the resources, expertise, and budgetary and organizational authority to fulfill its architectural responsibilities, and (3) direct this single entity to ensure that every ATC project conforms to the architecture unless careful, thorough, and documented analysis supports an exception.

    Agency Affected: Department of Transportation

  3. Status: Closed - Implemented

    Comments: FAA recently hired a CIO who reports directly to the Administrator.

    Recommendation: Given the importance and the magnitude of the information technology initiative at FAA, GAO recommends that a management structure similar to the department-level CIOs as prescribed in the Clinger-Cohen Act be established for FAA.

    Agency Affected: Department of Transportation


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