Our analysis of FAA major outage data from September 1994 through May 1996 at the Chicago, Dallas-Ft. Worth, New York, Washington, and Cleveland en route centers showed that DCC accounted for 10 of the 21 outages, or about 48 percent. FAA has specified a DCC system availability requirement of 99.9 percent. FAA attributes increasing MTTR to depleted inventories of out-of production DCC spare parts and a shortage of experienced DCC repair technicians. Decreases in DCC availability will result in costly delays for airlines and passengers. FAA Has Made Good Progress on DCCR but Can Reduce Risk Further

Thus far, FAA has made good progress on its DCCR acquisition, but much remains to be accomplished. To FAA’s credit, the fourth and final software build has completed integration testing, and some formal system-level test and demonstration activities have occurred. However, the number of software defects being found is slightly higher than projections, and despite the fact that FAA’s defect fix rate has kept pace with the higher numbers and its DCCR defect trend lines are favorable when considering defect severity, unresolved defects delayed the start of concurrent system-level testing at the Technical Center and the first site by several weeks. Also to FAA’s credit, it has prudently made formal risk management and quality assurance integral components of the acquisition. However, two risks associated with concurrent test plans are not being formally addressed—managing contention for limited test staff among three concurrent test activities, and controlling and synchronizing changes to three DCCR system test configurations. DCCR Is Ahead of Schedule and Contractor Reports Show the Contract Is Under Budget

According to the publicly announced DCCR schedule, the first site is to be operationally ready on October 1997. As such, each increment of tests is designed to sequentially test for and disclose different information about the system’s ability to perform as intended. By not formally managing these risks, FAA is increasing the chances that they will be overlooked and adversely affect DCCR. FAA has thus far made good progress in its efforts to replace DCC with DCCR. Recommendations

To maximize the likelihood of delivering promised DCCR capabilities on time and within contract budgets, we recommend that you direct the FAA Administrator to ensure that (1) contention for human test resources during DCCR concurrent test activities and (2) change control over system test configuration baselines during concurrent test activities are managed as formal program risks. Our objectives were to determine (1) the portion of the recent major outages experienced at the five DCC-equipped en route centers that were attributable to DCC, (2) whether DCC was meeting its system availability requirement, (3) FAA’s projections of future DCC outages and availability, and (4) whether FAA was effectively managing the DCCR acquisition to ensure delivery of specified capabilities on schedule and within estimated cost. To assess future DCC outages and availability, we obtained FAA projections of the number of DCC outages and the associated MTTR for these outages for calendar years 1996 through 2000, reviewed FAA’s Supportability Review of Display Channel Complex (DCC) and Computer Display Channel (CDC) (Initial Report), dated May 1995, and Supportability Review Update of Display Channel Complex (DCC) Hardware, dated March 1996, and interviewed Air Traffic Services officials responsible for these reports.
Why GAO Did This Study

GAO reviewed the Federal Aviation Administration's (FAA) Display Channel Complex Rehost (DCCR) project, intended as an interim replacementof the Display Channel Complex (DCC), focusing on: (1) recent outages caused by DCC; (2) whether DCC was meeting its system availability requirement; (3) FAA's projections of future DCC outages and availability; and (4) whether FAA was effectively managing the DCCR acquisition to ensure delivery of specified capabilities on schedule and within estimated cost.

What GAO Found

GAO found that: (1) DCC, built and deployed over 30 years ago, is critical to FAA's ability to display aircraft situational data in five of FAA's 20 air route traffic control centers; (2) DCC is also responsible for most of the major outages at the five centers from September 1994 through May 1996, accounting for about 48 percent of the total number of major outages and nearly 87 percent of unscheduled system downtime associated with these outages; (3) according to FAA, DCC was able to exceed its availability requirement from fiscal year (FY) 1990 to 1993, on average at the five centers, because of heroic maintenance efforts using "chewing gum and chicken wire"; (4) however, it fell slightly short of the requirement in FY 1994 and 1995, and FAA expects availability to decrease further because of shortages of spare parts and experienced DCC technicians; (5) decreases in DCC availability will result in costly delays for airlines and passengers; (6) FAA has made good progress in acquiring DCCR, but much remains to be accomplished; (7) thus far, the fourth and final DCCR software build is complete, and the number of reported software defects, while cumulatively slightly higher than projections, is showing a favorable trend when adjusted for defect severity; (8) also, FAA is ahead of schedule in completing informal system-level tests, formal testing is generally on schedule, and the first site is ready to begin the system acceptance process; (9) DCCR's development has benefitted from formal risk management and quality assurance programs, and FAA has plans in place to accelerate completion of formal system-level tests; (10) contractor financial reports show that DCCR is under spending estimates; (11) in light of its progress to date, FAA has an opportunity to deliver promised DCCR capabilities on time and within contract budgets; (12) the likelihood of doing so can be increased, however, by acting to mitigate two known risks associated with remaining development activities; (13) specifically, FAA's test plans call for conducting three system-level tests concurrently rather than sequentially, as is normally done; (14) by doing so, FAA expects to implement DCCR early; (15) however, FAA is not formally managing two risks associated with DCCR concurrent testing, which are: (a) staffing three test activities at the same time and thus potentially spreading test personnel too thin; and (b) not defining how it will control and synchronize changes to three system test configurations so as to prevent configuration differences among the three during testing; and (16) by formally managing these risks, FAA will greatly reduce the chances of them impeding future DCCR progress.