Summary: Pursuant to a congressional request, GAO reviewed: (1) how effectively the Federal Aviation Administration (FAA) identified and assessed equipment performance problems at its en-route centers, which control traffic between airports; and (2) ways in which FAA could better utilize its current maintenance databases to manage its air traffic control (ATC) systems' maintenance effort.
GAO found that: (1) the FAA assessment of en-route center equipment performance was incomplete because it only analyzed overall system performance data, and failed to analyze specific equipment failures; (2) although FAA reported its en-route system to be about 99 percent reliable, it did not consider the fact that much of the aging equipment within those systems experienced problems; (3) although FAA procedures require centers to record all equipment failures in the Maintenance Management System database, they failed to consistently do so; (4) from August 1989 through July 1990, an analysis of one en-route center showed that the center experienced 1,935 equipment failures or malfunctions; (5) FAA relied on information from field maintenance personnel to assess equipment performance; (6) systems failed infrequently, primarily because FAA designed its en-route ATC system with redundant equipment to prevent one equipment failure from causing a full system outage; (7) as FAA equipment fails, the margin of error provided by redundancy and equipment failure risks increases, causing system performance to deteriorate; and (8) FAA can use system data to make management decisions based on a more thorough measurement of equipment performance, but in order for FAA to utilize such data to the fullest extent, it must address several database problems by refining data definitions and reporting guidelines.