BOSTON


— The U.S. Air Force




likely will award a multi




billion dollar contract to build the next generation of GPS navigation and timing satellites in early April, according to the service official overseeing the program.

The delay on the contract award, which




previously had been expected in late 2007,




likely will contribute to pushing the first launch of the GPS 3 satellites about six months from late 2013 into 2014, according to Col. David Madden, GPS wing commander at the Space and Missile Systems Center in Los Angeles.

Lockheed Martin Space Systems of Sunnyvale, Calif., and Boeing Integrated Defense Systems of St. Louis




are leading the two teams competing for the GPS 3 contract.

While the Air Force




currently is planning to launch the first GPS 3 spacecraft




in 2014, the contract for the satellites includes incentives for the contractor to launch up




to a year earlier than that, Madden said in a Jan. 8 interview.

In keeping with the incremental fielding strategy that is part of the “back-to-basics” philosophy that the Air Force adopted for space acquisition in 2005, the service plans to introduce the improved capabilities that are part of the GPS 3 program over the course of three blocks of satellites.

In fact, Ron Sega, the architect of the back-to-basics approach to spacecraft acquisition who retired from the post of Air Force undersecretary last fall, said in an April interview that GPS 3 would serve as a model for that approach.



Block 3A will feature a satellite bus based on designs that the competitors have used with commercial communications spacecraft that can accommodate the capabilities envisioned with all three blocks of satellites, Madden said. The first block will include increased signal power that can help troops overcome enemy jamming attempts, better signal accuracy, and compatibility with the European Galileo navigation satellites, he said.



Improvements slated for Block 3B, which is scheduled to launch beginning in 2017, include satellite to satellite cross links that can speed the updating of information to the satellites from operators on the ground, Madden said. While cross links are used on the GPS satellites on orbit today to pass information from the nuclear detection payloads carried aboard the satellites, they have not been used for the navigation and timing signals, he said. Separate cross links will be used on GPS 3 for both the nuclear detection and navigation and timing signals, he said.

The GPS Block 3C satellites, which are scheduled to begin launching in 2019, will feature spot beams that can be focused on particular areas of military operations to boost the signal power in order to give the signals added strength to help thwart enemy jamming attempts, Madden said.

GPS users will need to receive signals from at least four GPS 3 satellites




to take advantage of the new capabilities, Madden said. The Air Force plans to launch two of the new satellites in 2014, with three more the following year, he said. While the service could opt to place them in orbits optimized for bringing the new capabilities online faster over particular areas of interest, the primary focus will be on replacing aging satellites, he said.




While users will need devices specifically designed to work with GPS 3 to take advantage of the satellites’ new capabilities, the satellites will feature legacy signals to ensure




existing devices will continue to work, Madden said.

Much of the attention to the advanced capabilities with GPS 3 has focused on the ability of the satellites to counter enemy jamming attempts. However, as GPS has become increasingly important to a variety of non-military applications, maintaining civilian access to the signals has become a homeland security priority as well.









The Air Force’s 2nd Space Operations Squadron at Schriever Air Force Base in Colorado Springs, Colo., which operates the satellites, will put additional focus on monitoring the civil signals for non-military customers like the Federal Aviation Administration, Madden said.






Madden noted that non-military customers will be able to take advantage of improved accuracy with GPS 3 that can make the signals more reliable for tasks ranging from air traffic management to automated farming functions, Madden said.

An Air Force chart indicates that the GPS 2A and GPS 2R satellites that are on orbit today are accurate to about 1.15 meters and 0.57 meters respectively; the GPS 3 satellites are designed to provide signal accuracy of up




to 0.25 meters. The chart also notes that the accuracy of GPS satellite data tends to outpace design specifications, as GPS 2A and GPS 2R were both designed to be accurate to 3 meters, according to the chart.



The GPS 3 satellites’ compatibility with the Galileo constellation also means that users will have increased access to navigation signals, reducing the likelihood of losing contact, Madden said.

In addition to the block acquisition approach that is intended to help GPS 3 avoid the type of cost growth and schedule delays that has plagued other space programs like GPS 2F, the Air Force has taken several other steps that are part of the back-to-basics philosophy, Madden said.

These steps include budgeting to a confidence level of 80 percent of




the cost estimate




– versus the previous approach of a 50 percent confidence level




– using an award fee structure that does not reward poor performance, and relying on technology that




already has been demonstrated in space, he said.