USAF, Lockheed Develop Testbed To Validate GPS 3 Satellite Components
SAN FRANCISCO — Lockheed Martin engineers, preparing to build as many as 32 next-generation GPS 3 satellites for the U.S. Air Force, will spend the next several months focusing on completing the development of spacecraft components and integrating them onto a satellite that is not intended to fly.
The GPS Non-Flight Satellite Testbed (GNST) is designed to reduce risk in the GPS 3 spacecraft production program by validating the spacecraft’s design and verifying that support and testing equipment is ready when the first flight vehicles are built. It is part of the Air Force back-to-basics strategy, which emphasizes rigorous, up-front systems engineering in an effort to identify potential problems and find solutions early in the acquisition cycle.
“GNST gives us an opportunity to make sure that when we get to the first flight vehicle, all the pieces will come together in an integrated fashion,” said Keoki Jackson, GPS 3 program manager for Denver-based. “It’s not just the hardware and software components, it’s making sure that all the mechanical ground support equipment fits, checks out and operates properly.”
Lockheed Martin plans to complete construction of the GNST late this year at the company’s facility in Newton, Pa., before shipping it to Denver, where company officials will perform integration and testing in a manufacturing facility designed to accommodate as many as four satellites at a time. GNST will then be sent to Cape Canaveral Air Force Station in Florida to ensure that work crews there are prepared to process the satellite for launch.
By creating that testbed, Jackson said he expects manufacture and testing of the first flight vehicle to run smoothly. GNST is being built approximately one year ahead of the first GPS 3 flight vehicle. That timeline gives Lockheed Martin officials time to identify any problems that occur during processing of the testbed and solve them before starting work on the first satellite destined for orbit, Jackson said.
Lockheed Martin also has ordered the majority of the parts and materials required to build the first two GPS 3 flight vehicles, and company engineers have tested early versions of three flight processors to ensure that they will work well together, Jackson said. The processors are designed to support the GPS 3 satellite’s communications component, navigation equipment and spacecraft bus, he added.
In 2008, the U.S. Air Force awarded a $1.4 billion contract to Lockheed Martin to develop the first block of GPS 3 satellites, known as GPS 3A. The contract covered development and production of the first two spacecraft and included options for 10 additional satellites.
The Air Force plans to buy those 10 additional satellites with development and procurement funding in its 2012 through 2019 budgets, Christina Greer, spokeswoman for the Air Force Space and Missile Systems Center in Los Angeles, said March 28 in an emailed response to questions. In 2012, the service requested $978 million in development and procurement funding for GPS 3. If appropriated by the U.S. Congress, that money would cover all technical support and systems engineering associated with the GPS 3A spacecraft, Greer added.
In February 2010, the Air Force awarded an $886 million contract to Raytheon Intelligence and Information Systems of Garland, Texas, to develop blocks one and two of the next-generation GPS 3 ground segment, which is called GPS OCX. The ground systems, which will take over support of the current fleet of GPS 2 spacecraft in addition to supporting the next generation, are scheduled to become fully operational in August 2015.
The U.S. Government Accountability Office (GAO) highlighted the time lag between the GPS 3 spacecraft and ground segments in a September report. Air Force officials responded that a streamlined version of the OCX system would be available to support the launch and checkout of the first GPS 3 satellite on-orbit.
GAO officials also cited concerns that any delay in OCX development would have serious repercussions for the utility of the GPS constellation. The OCX program, however, remains on schedule, said Kelly Vandel, Raytheon’s deputy OCX program manager. The company is taking an iterative approach to developing the new ground segment. Phase A, the first iteration, was completed prior to the 2010 contract award. Approximately 90 percent of the software developed for Phase A is used in Phase B, Vandel said.
The GPS 3 ground systems are designed to improve the efficiency of GPS operations, which means fewer people will be needed to operate ground stations. OCX also is designed to shore up certain vulnerabilities in the previous GPS 3 network, Vandel said. He declined to identify those vulnerabilities, but said OCX will offer heightened software security.
The primary OCX ground station will be based at Schriever Air Force Base in Colorado with a backup capability at Vandenberg Air Force Base in California. In addition, Raytheon is preparing to install GPS receivers in 17 stations around the world to monitor satellite signals and to build new ground antennas to transmit signals to the satellites.
The GPS 3 constellation is designed to offer improved signal accuracy for all users and higher power levels for military applications. The first GPS 3A satellite will offer three times the military signal strength of its predecessors. In addition, the next generation of GPS satellites is being designed to remain operational for 15 years, nearly twice as long as the standards set for the previous generation.