Y2K
GPS Control Segment Impact

Just as with any other system that exists today there is the possibility of an upcoming threat. Of the DoD's myriad systems, the Global Positioning System is most vulnerable to malfunction and most likely to suffer devastating consequences due to year 2000 code problems, DOD officials have concluded. DOD plans for all military aircraft to use GPS for navigation by 2000 and the military's growing dependence on GPS-guided smart bombs have heightened Pentagon concerns about the vulnerability of the navigation system to year 2000 glitches. The GPS year 2000 problem is threefold and reflects on all three components of the navigation system. According to documents provided to Congress earlier this month, the year 2000 problems within the space segment can be found in two pieces of ground equipment: the Bus Ground Support Equipment vehicle checkout stations and the Boeing Mission Operation Support Center (MOSC). Software to correct the year 2000 problem in the Bus Ground Support Equipment vehicle checkout stations already exists, and DOD will install it during the normal systems maintenance lifecycle. But the MOSC date code problem lies in its underlying commercial products. So DOD will replace MOSC with the Integrated Mission Operation Support Center (IMOSC), which it expects to finish in December 1999. The GPS JPO is working to push the completion date up at least six months to June 1999. The IMOSC project is part of a $1.3 billion GPS Block IIF satellite contract that DOD awarded to Boeing Co. last April. Of the ground control segment, the software needing date code fixes generates the uplink code to the satellites. It was written in the 1970s and uses only two-digit date fields. The original plan was to replace the old code as part of a modernization of the ground control segment, or Architecture Evolutionary Plan (AEP). But schedule delays have pushed AEP's operational beginning to mid-2000. If schedule delays persist there lies a secondary plan. GPS JPO officials have decided to rewrite some of the existing legacy code for the ground control segment at a cost of $7.6 million. Lockheed Martin Federal Systems has been assessing the code and will rewrite it under an existing maintenance contract. Until then, GPS JPO will incrementally integrate modifications as part of its normal software maintenance releases.