NEWTOWN, Conn. - GPS IIF satellite construction is complete, and all of the 12 satellites have been launched. With all GPS IIF satellites now in orbit, the Air Force has turned its attention to the GPS III. The program has experienced a troubled development cycle. The latest problem was the discovery of small cracks in a ceramic capacitor. Although the problem was fixed, it delayed launch.
The program has achieved a number of milestones. The program reached its Critical Design Review in August 2010 and System Design Review in July 2011. The GNST's payload was powered on for the first time in May 2012. In May 2015, the GPS III propulsion core was integrated into the space vehicle, and it completed thermal vacuum tests were completed in January 2016.
Even as milestones continue to be met, the Air Force has further delayed the program. These delays are not due to development problems. Instead, the Air Force wants to open more GPS launches to competition and to purchase satellites in so-called block buys to reduce cost. The later launch dates will enable the USAF to achieve its goals. The first launch is now scheduled for 2018, with two per year between 2019 and 2021 and three launches per year after that.
While the USAF originally planned to order all GPS III satellites from Lockheed Martin, the service now plans to reopen the competition. Lockheed Martin is under contract to build 10 spacecraft. However, in May 2016, the Air Force awarded production feasibility assessment three contracts to study production feasibility with Lockheed Martin, Boeing, and Northrop Grumman. One of the three companies will eventually be selected to build 22 satellites.
No matter which company receives the contract to build the remaining GPS III spacecraft, deliveries will continue at a steady pace throughout the forecast period. Satellites will need to continue to be launched to maintain global navigation coverage as older satellites reach the end of their useful lifespans.