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GAO Report on GPS. “Significant Challenges in Sustaining and Upgrading Widely Used Capabilities”. Presented on 30 April 2009 to Subcommittee on National Security and Foreign Affairs, Committee on Oversight and Government Reform, House of Representatives Released to the public on 8 May 2009
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GAO Report on GPS “Significant Challenges in Sustaining and Upgrading Widely Used Capabilities” Presented on 30 April 2009 toSubcommittee on National Security and Foreign Affairs, Committee on Oversight and Government Reform, House of Representatives Released to the public on 8 May 2009 http://www.gao.gov/new.items/d09325.pdf
Context • 11 of 46 papers at US Hydro 2009 depend upon the assumption that GPS is a reliable infrastructure, that can only get better. • This assumption may be too optimistic
Subsystem Status (Sept 2008) 33 in orbit 21 okay 4 unhealthy 7 last clock Riedesel, CGSIC48 [05] Sept 08
GPS signal evolution Previouslaunches Launchesfrom Dec 2005
GPS Ground Station Upgrades Military use of modernized signal Army, Navy, Marine Corps fully equipped with modernized GPS equipment by 2025, 12 years after IOC - 18th modernized launch (2013) 10 years after FOC - 24th modernized launch (2015)
IIF Procurement problems • Significant technical problems (not yet solved) • New acquisition policy relaxed oversight and quality inspections, introducing problems • Contractor changed locations, teams, and ownership several times (7 project managers so far) • Requirements creep • 3 years behind, 120% over budget
Block III acquisition • Divide into 3 evolutionary phases • IIIA - stronger military signal, L1C • IIIB - crosslinks • IIIC - improved military antijam • Two civil payloads for IIIB, IIIC • Distress Alerting Satellite System (DASS) • Satellite Laser Ranging retromirrors • GAO report judges planned delivery schedule too optimistic, and predicts 2 year delay
http://www.glonass-ianc.rsa.ru/pls/htmldb/f?p=202:20:11394786619100357095::NO:::http://www.glonass-ianc.rsa.ru/pls/htmldb/f?p=202:20:11394786619100357095::NO:::
Bottom line “For civil and commercial users, one possible impact of a smaller GPS constellation could be an increased use of other positioning, navigation and timing (PNT) services, including those expected to be offered through Europe’s Galileo system . . .” Department of State asks for higher priority for US expert participation in international PNT activities, to ensure compatibility with GPS is maintained.