Air Traffic Control:

Voice Communications System Continues to Encounter Difficulties

IMTEC-89-39: Published: Jun 1, 1989. Publicly Released: Jun 1, 1989.

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Pursuant to a congressional request, GAO evaluated the Federal Aviation Administration's (FAA) efforts to implement its Voice Switching and Control System (VSCS), a computer-controlled voice system designed to significantly improve air traffic controllers' communications capabilities.

GAO found that: (1) FAA continues to encounter significant cost, schedule, and technical difficulties in implementing VSCS, with cost estimates tripling from $258 million in 1982 to over $786 million, and up to 6-year schedule slippages; (2) the two prototype contractors continue to experience difficulties in designing hardware and software capable of meeting VSCS performance requirements; (3) delays in implementing VSCS will adversely affect implementation of the Advanced Automation System, intended to replace work stations and some computer hardware and software to increase controller efficiency and effectiveness; and (4) FAA reduction in VSCS prototype testing requirements, intended to facilitate an earlier award of a production contract, could result in higher costs and longer delays if it is later determined that the equipment does not meet performance requirements.

Recommendations for Executive Action

  1. Status: Closed - Implemented

    Comments: The Department of Transportation (DOT) stated that FAA will, prior to awarding the VSCS production contract, require certain factory acceptance tests to be conducted, witness and evaluate test results, and conduct two sets of controller tests. In January 1991, the Administrator, FAA, also declared that the FAA goal is to complete factory acceptance testing and controller operational tests.

    Recommendation: The Secretary of Transportation should direct the Administrator, FAA, not to award the VSCS production contract until, at a minimum, the agency has: (1) the results of complete factory acceptance testing to ensure that prototypes meet system requirements; (2) an independent verification of the results of the contractors' testing, including an assessment of the system's performance under maximum work loads; and (3) an assessment of the operational suitability of the system.

    Agency Affected: Department of Transportation

  2. Status: Closed - Implemented

    Comments: DOT stated that FAA will continue to closely monitor the progress of the AAS and VSCS programs to detect any early indications of adverse schedule impacts. DOT stated that, should such indications arise, FAA will then prudently explore possible changes to contracts. Therefore, DOT is not directing FAA to explore possible changes at this time.

    Recommendation: To reduce the government's potential liability, the Secretary of Transportation should direct the Administrator, FAA, to explore possible changes in the Advanced Automation System (AAS) contract in order to lessen the possible adverse impact of VSCS delays.

    Agency Affected: Department of Transportation


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