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Global Positioning Systems Wing Completes GPS III Critical Design Review



LOS ANGELES AIR FORCE BASE, Calif. -- The Global Positioning System Block IIIA satellite program completed its Critical Design Review at Lockheed-Martin Newtown, Pa., Aug. 19--two months ahead of schedule. This event synthesized the final design and operational concept and was the culmination of 63 lower level CDRs held during the past 12 months. The CDR ensured that the satellite requirements and detailed design are complete and under configuration control, and that the satellite, support equipment, and production lines are ready to start manufacturing. This CDR was attended by more than 350 people representing 46 different organizations including the GPS Wing, GPS users, numerous civilian agencies and the Pentagon.

The GPS III program is built on a "back to basics" foundation which emphasizes stable personnel, stable requirements, stable funding and rigorous systems engineering. The Department of Defense and Department of Transportation play key roles in advancing GPS capabilities and their steady leadership has contributed immensely to the success of GPS III in terms of requirements and funding. To date, the Air Force and DOT have continued to fully fund the Engineering and Manufacturing Development phase, avoiding the crippling effects that can come with budget instability.

The Air Force also recognized that delivering on its commitments depends on stable program office leadership, and enacted three-year or longer tours for critical acquisition personnel. Newly retired Col. David Madden, held the positions of vice commander and commander of the GPS Wing from 2006 to 2010 and Lt. Col. Donald Frew has been in place as program manager since shortly after the contract's award in 2008 through integrated baseline review, preliminary design review and critical design review. He will remain in his current position for at least another year as GPS III begins manufacturing.

Rigorous systems engineering at the beginning of the program has ensured that designers understand what their systems must do to effectively meet overall satellite performance requirements and also ensured that the individual components will work together as planned when they are integrated onto the space vehicle. The GPS Wing and Lockheed Martin empowered the individual Integrated Product teams and systems engineering leadership with the authority to recommend the best design decisions for the program in terms of overall system risk. For example, the navigation payload team recognized that the Mission Data Unit that generates the navigation signals would not have all of its drawings or its field programmable gate array design complete in time to meet the scheduled payload subsystem CDR date. The Lockheed Martin systems engineering team and the MDU subcontractor, ITT, worked with the government to reschedule the subsystem CDR to ensure proper preparation across the whole team.

"We immediately called timeout, then sat down with Lockheed Martin, ITT, and Aerospace to assess the risk of moving forward with the current level of design maturity. We established a closure plan and delayed the review until we were confident that all entrance criteria were fully satisfied, said Capt. Gina Peterson, the government's Navigation Payload lead." The MDU CDR was successfully completed three weeks later.

One of the significant highlights of the CDR was the completion and government approval of 100 percent of the 577 Source Control Drawings (SCD) for custom parts for the GPS IIIA satellite. SCDs describe required build, test, screening, and other unique requirements for specialized parts for which a standard Space Quality Baseline part does not exist. Parts problems, late deliveries and insufficient part quality are traditional sources of risk and cost growth on most space programs. The approval of SCDs at the GPS IIIA CDR is a significant risk reducer.

David Podlesney, GPS III Program Director for Lockheed Martin, compared this to the GPS IIR program, also built by Lockheed Martin. "At this stage of the GPS IIR program, we were just beginning to count how many SCDs we needed. On GPS IIIA we have 100 percent of our SCDs through government approval and are placing orders for qualification and flight parts," he said.

Successful execution for the CDR campaign depended on detailed planning which began immediately after the completion of the Preliminary Design Review in May 2009. Keem Thiem, GPS Squadron; Christian Reascos, Systems Engineering & Integration contractor; and Doug Chalmers and Marty O'Conner, Lockheed Martin, led the planning team. Together they mapped out an intricate schedule for all data deliveries required to satisfy the program's stringent design criteria. They also managed a weekly review and feedback process that allowed the prime contractor, subcontractors, suppliers and the government to clearly understand expectations and key dependencies necessary for an integrated detailed design. A key precept of the GPS III approach was to evaluate the design and its artifacts prior to arriving at each subsystem, element, and spacecraft CDR event so that key risks could be identified and mitigated ahead of the review.

The depth of analysis and review conducted by the GPS III Squadron and the Lockheed Martin-led industry partners was unprecedented in the last 20 years.

"This was by far the best CDR I've seen in my 35 years in the space business. The quality of the data provided by the contractor, the depth of review by the government, and the partnership in which the campaign was conducted were simply extraordinary, " said Mike Dunn, GPS Wing technical director.

"This is one of the most outstanding government/industry partnerships I've seen in 25 years," said Col. Chris Warack, GPS Space Group commander.

Throughout the campaign, the GPS III squadron relied on excellent leadership across the board. "I am extremely proud of the team," said Lt. Col Frew. "Everyone pulled together to make this happen, and we did it while maintaining uncompromising quality standards."

The foundation set by this CDR puts the program on the best possible footing for continued success. The next challenges are to effectively transition to manufacturing and test, and to effectively manage traditional challenges such as flight software and manufacturing process escapes. Not everything will go perfectly; however, the team believes the foundation is solid and the program is strongly postured to overcome the upcoming challenges. The successful GPS IIIA spacecraft CDR continues the high standard set by the Air Force in managing the GPS Program so it continues to be the Gold Standard for positioning, navigation and timing around the world.