GPS Block IIIF
GPS Block IIIF, or GPS III Follow On (GPS IIIF), is the second set of GPS Block III satellites, consisting of up to 22 space vehicles. The United States Air Force began the GPS Block IIIF acquisition effort in 2016. On 14 September 2018, a manufacturing contract with options worth up to $7.2 billion was awarded to Lockheed Martin. The 22 satellites in Block IIIF are projected to be delivered starting in 2026, with launches estimated to last through at least 2034. Development. The U.S. Air Force employed a two-phase competitive bid acquisition process for  the GPS Block IIIF satellites. Phase One: Production Feasibility Assessment. On 5 May 2016, the U.S. Air Force awarded three Phase One Production Readiness Feasibility Assessment contracts for GPS III Space Vehicles (SV's) 11+, one each to Boeing Network and Space Systems, Martin Space Systems Company, and Northrop Grumman Aerospace Systems. The phase one contracts were worth up to six million dollars each. During the phase one effort, both Boeing and Northrop Grumman successfully demonstrated working navigation payloads. Phase Two: Satellite Manufacturing. On 19 April 2017, the US Air Force Space Command announced the start of the second  phase of its acquisition strategy with the publication of a special notice for an "Industry Day" for companies planning on bidding for the contract to manufacture GPS III vehicles 11+. During the Industry Day event, the Air Force shared the tentative acquisition strategy which it will use to evaluate proposals, then solicited feedback from potential bidders. In July 2017, the Deputy Director of the U.S. Air Force GPS Directorate stated the acquisition strategy for GPS Block IIIF would be to award the manufacturing contracts for all 22 Block IIIF satellites to the same contractor. In November 2017, the Deputy  Director of the US Air Force's GPS Directorate announced the name of the second tranche of GPS III satellites was "GPS Block IIIF". Also in November 2017, it was announced that development of the fully digital navigation payload for GPS Block IIIF satellites had completed. The Block IIIA program schedule was delayed multiple times due to issues with the navigation payload. Bidding. While the Air Force originally expected to publish the formal Request For Proposals (RFP) for GPS Block IIIF production in September 2017, it was not released until 13 February 2018. The RFP was for a firm-fixed  price (FFP) contract for a single company to manufacture all 22 space vehicles. All three participants from phase one (Boeing, Lockheed Martin, and Northrop Grumman) were believed to be likely to submit proposals. The government held a pre-proposal conference in El Segundo, California, to be held on 15 March 2018 for potential bidders to ask the Air Force questions about the solicitation. The submission deadline for proposals was 12:00 pm Pacific Daylight Time (PDT) on 16 April 2018. The bid status of companies who participated in phase one, in alphabetical order: Funding. Procurement funds for GPS Block IIIF satellite  manufacturing will be allocated from the federal budget, starting with Fiscal Year 2018 (FY18). FY 2020 provided funding to procure GPS IIIF SV-13 for delivery in September 2026. FY 2021 funded procurement of SV14 and SV15, with deliveries in November 2026 and February 2028. FY 2022 will fund procurement of SV16 and SV17, with deliveries in June and October of 2028. Contract awards. On 14 September 2018, the Air Force awarded a manufacturing contract with options worth up to US$7.2 billion to Lockheed Martin. The Space and Missile Systems Center exercised options on 26 Sept 2018 for the first  two satellites known as Space Vehicles 11 and 12. The $1.3 billion contract also included development costs. Options for SVs 13 and 14 were authorized in October 2020 for $511 million. Three more GPS IIIF satellites are planned to be placed under contract in 2022. Design. GPS IIIF is an evolution of GPS III, which uses the A2100 bus as its core. The new models use the modernized LM2100 bus along with a fully digital navigation payload from L3Harris, a significant upgrade from the previous 70% digital payload used in GPS III. An upgraded version known as the  LM2100 Combat bus will be used starting with the third service vehicle. It will enable on-orbit servicing at a later date, which may include hardware upgrades, component replacement, or refuelling. Medium Earth Orbit Search and Rescue (MEOSAR) payloads are being provided by the Canadian government on behalf of the Canadian Armed Forces. The time it takes to detect and locate a distress signal will be reduced from an hour to five minutes, along with greatly improved accuracy in locating a distress beacon. Laser Retro-reflector Arrays (LRAs) will be built by the Naval Research Lab. This is a passive  reflector system that improves accuracy and provides better ephemeris data. The National Geospatial-Intelligence Agency (NGA) will fund the integration costs of the LRA. Other significant enhancements include: unified S-Band (USB) interface compliance, integration of hosted payloads including a redesigned USNDS payload, Energetic Charged Particles (ECP) sensor, and Regional Military Protection (RMP) capabilities that provide the ability to deliver high-power regional Military Code (M-Code) signals in specific areas of intended effect. The Air Force has identified four "technology insertion points" for GPS Block IIIF. These four points are the only four times during the block's lifecycle  where new capabilities will be allowed to be introduced to Block IIIF satellites. Satellites. The 22 GPS Block IIIF satellites are scheduled for launch between FY2025 and FY2034. The Space and Missile Systems Center exercised options on 26 Sept 2018 for the first two satellites known as Space Vehicles 11 and 12. The $1.3 billion contract also included development costs. Options for SVs 13 and 14 were authorized in October 2020 for $511 million. Three more GPS IIIF satellites are planned to be placed under contract in 2022. SV 11 is expected to be “Available For Launch” in  February 2026. SV12 AFL is projected for August 2026.