GPS III is a Lockheed Martin satellite that sends positioning and timing signals to civil and military users.
lockheed-gps-iii GPS III is a navigation satellite for the US Space Force. Its signals give military and civil users their position and the time, and this generation adds a civil signal, better accuracy and more resistance to jamming. Lockheed Martin built the satellite body, or bus, on its A2100 design, and ITT built the navigation payload.
Each satellite hosts three enhanced rubidium atomic clocks, with a fourth slot kept for an experimental clock design such as a hydrogen maser. The tanks that hold the fuel and the pressurising gas are made of lightweight, high-strength composite. One antenna has eight deployable elements of the jack-in-the-box type.
Navigation satellite for the GPS constellation, giving positioning and timing signals to military and civil users. GPS III adds a civil signal, better accuracy and anti-jamming, with a 15-year design life.
The payload computer, called the mission data unit, includes the waveform generator first used on the GPS IIR-M satellites. L-band transmitters send the L1, L2, L3 and L5 signals. Three enhanced rubidium atomic clocks keep time, and a fourth slot is kept free for an experimental clock.
A liquid apogee engine handles the final move into orbit. Thrusters of 5 lbf, or pounds of force, make the large manoeuvres, and the smaller 0.2 lbf thrusters handle coarse ones such as periodic station keeping. Orbital ATK made the propellant and pressurant tanks from lightweight, high-strength composite.
Power comes from solar arrays, batteries and a power regulation unit. To control its orientation the satellite has coarse sun sensors, earth sensors and an inertial measurement unit, with reaction wheels and magnetic torque rods for fine manoeuvres.
The antenna subsystem has an Earth-coverage L-band panel, S-band antennas and UHF antennas. A further antenna has eight deployable elements of the jack-in-the-box type, designed and made by Northrop Grumman Astro Aerospace. General Dynamics was subcontractor for the communications payload.
In the three enhanced atomic clocks on each satellite. SV10 also carried a demonstration digital rubidium clock.
The propellant and pressurant tanks, made by Orbital ATK. The type of composite is not named.
The 2011 design names these for the batteries, though lithium-ion was also mentioned as lighter. The flown chemistry is not confirmed.
Most GPS III satellites flew on SpaceX Falcon 9 rockets, whose first stage burns nine Merlin engines. SV02 flew on a United Launch Alliance Delta IV in August 2019. Lockheed Martin built them on its A2100 bus, borrowing design elements from the earlier GPS Block IIR and IIR-M satellites. ITT, later L3Harris, built the navigation payload. SV10, launched on 21 April 2026, paves the way for the GPS IIIF series.
SpaceX
launched SV01 (2018), SV03, SV04, SV06 and SV09 per Lockheed; Wikipedia lists Falcon 9 Block 5 for SV05, SV07, SV08 and SV10 too
second Lockheed-confirmed Falcon 9 flight
Lockheed-confirmed Falcon 9 flight, January 2023
SpaceX
Falcon 9 first stage burns nine Merlin engines (2010 page; Block 5 flights use the Merlin 1D family, linked to the catalog hub)
launched SV02 in August 2019
design elements and the waveform generator come from the IIR and IIR-M satellites
expandable GPS III design is based on the A2100 bus
navigation payload
communications payload subcontractor
composite propellant and pressurant tanks
JIB deployable antenna elements
Lockheed provides early on-orbit operations before handover
Little is said about what the structure, panels, solar cells and thermal blankets are made of. Published figures for the satellite's mass do not agree, and the flight battery chemistry is unconfirmed. The description of the bus dates from the design stage, so the flown hardware may differ.
What is written above is built from these numbers and quotes. Each row links to the page it was taken from. Get all of it as JSON, or ask our MCP server.
| What | Value |
|---|---|
| Design life | 15 years (12-year mean mission duration) |
| Bus | Lockheed Martin A2100 |
| SV01 mass | About 4,400 kg (9,700 lb); secondary source |
| Atomic clocks | Three enhanced rubidium clocks per satellite |
| Final block launch | SV10 launched 21 April 2026 |
| Launch mass (Wikipedia) | 3,880 kg (8,550 lb) |
| Dry mass (Wikipedia) | 2,269 kg (5,002 lb) |
| End-of-life power (Wikipedia) | 4,480 W |
| Operational orbit | about 12,550 miles above Earth |
| Accuracy and anti-jamming | 3x better accuracy and up to 8x improved anti-jamming |
| Navigation accuracy requirement | 1.0 m user range error at 24 hours |
| M-code received power | at least -153 dBW at five degrees elevation |
| Production facility | GPS III Processing Facility near Denver, $128 million |
| Final launch | SV10, 21 April 2026, 2:53 a.m. ET |
| Mean mission duration | 12 years, with a 15-year design life |
| Bus variant (Wikipedia) | A2100M |
Each material named in the sources: where it is used here, which other products use it, and its key numbers when its material page exists.
Used in 2 partsAtomic frequency standards (3) · Digital Rubidium Atomic Frequency Standard (demonstration, SV10)
Used in 1 partPropellant and pressurant tanks
Used in 1 partBatteries
Only battery chemistry and clock element are named; structure materials are unpublished in sources found. Components, suppliers and links were added from public sources. A material is left blank where no source states it.
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Batteries“It consists of the solar arrays, nickel-hydrogen batteries, and the power regulation unit.” | nickel-hydrogennickel-hydrogen-cell | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Atomic frequency standards (3)“Each GPS III SV hosts three enhanced rubidium AFSs” | rubidiumrubidium | — | — |
| Navigation payload element (NPE)generates and transmits the navigation signals“The NPE includes the payload computer (the mission data unit or MDU), the L-band transmitters (L1, L2, L3, L5)” | Not said | — | Supplier: ITT (later Exelis, Harris, L3Harris) |
| Mission data unit (MDU) payload computerpayload computer with the waveform generator first used on GPS IIR-M“The MDU incorporates the waveform generator functionality first introduced in the modernized IIR-M SV.” | Not said | — | — |
| L-band transmitters (L1, L2, L3, L5)send the navigation signals“the L-band transmitters (L1, L2, L3, L5)” | Not said | — | — |
| Signal filtersfilter the L-band signals in the payload“and signal filters.” | Not said | — | — |
| Fourth clock slot (experimental frequency standard)slot for a new or experimental frequency standard such as a hydrogen maser; the three operational clocks are in the entry bom“The GPS III SV also includes a fourth slot for enhanced new or experimental frequency standard designs, such as a hydrogen maser.” | Not said | — | — |
| Digital Rubidium Atomic Frequency Standard (demonstration, SV10)advanced atomic clock demonstration flown on the final satellite“equipped with a demonstration Digital Rubidium Atomic Frequency Standard clock” | rubidiumrubidium | — | — |
| Optical crosslink demonstration payload (SV10)lets GPS satellites communicate directly in orbit“an optical crosslink demonstration payload” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Basic SV structure“The MSS consists of the basic SV structure, hinges, and the frangibolts for deployable elements.” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Enhanced crosslink transponder subsystem (ECTS)crosslink and command path of the network communications element“It consists of the enhanced crosslink transponder subsystem (ECTS)” | Not said | — | Supplier: General Dynamics (communications payload subcontractor) |
| Thin communications unit (TCU)distributes commands and collects telemetry“the thin communications unit (TCU) to distribute commands and collect telemetry, and the S-band boxes” | Not said | — | — |
| S-band boxesS-band radios of the network communications element“the thin communications unit (TCU) to distribute commands and collect telemetry, and the S-band boxes” | Not said | — | — |
| Hosted payload element (government-furnished equipment)hosts government-furnished equipment items“The HPE hosts several government-furnished equipment (GFE) items provided to GPS III.” | Not said | — | — |
| Earth coverage L-band antenna panelnominally Earth-pointing panel that radiates the navigation signals“The antenna subsystem consists of the Earth coverage L-band antenna panel, the S-band antennas, and the UHF antennas.” | Not said | — | — |
| S-band antennascommand and telemetry antennas“the S-band antennas, and the UHF antennas” | Not said | — | — |
| UHF antennasUHF antennas of the antenna subsystem“the S-band antennas, and the UHF antennas” | Not said | — | — |
| Deployable antenna with 8 JIB elementsdeployable antenna built from eight Jack-in-the-Box elements“Each satellite will carry an antenna with 8 JIB (Jack-in-the-Box type) deployable antenna elements, all designed and manufactured by Northrop Grumman Astro Aerospace” | Not said | — | Supplier: Northrop Grumman Astro Aerospace |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Coarse sun sensors, earth sensors and inertial measurement unitattitude sensors“coarse sun sensors, earth sensors, the inertial measurement unit (IMU), reaction wheels, magnetic torque rods for fine maneuvers” | Not said | — | — |
| Reaction wheelsattitude actuators“coarse sun sensors, earth sensors, the inertial measurement unit (IMU), reaction wheels, magnetic torque rods for fine maneuvers” | Not said | — | — |
| Magnetic torque rodsfine maneuvers“coarse sun sensors, earth sensors, the inertial measurement unit (IMU), reaction wheels, magnetic torque rods for fine maneuvers” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Solar arraysprimary power source; deployed after the satellite reaches its operational orbit“It consists of the solar arrays, nickel-hydrogen batteries, and the power regulation unit.” | Not said | — | — |
| Power regulation unitregulates power from the arrays and batteries“It consists of the solar arrays, nickel-hydrogen batteries, and the power regulation unit.” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Thermal control hardwareinsulation, reflectors, heaters, radiators, heat pipes and thermistors“It consists of insulation, reflectors, heaters, radiators, heat pipes, and thermistors.” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Bus computer (on-board computer, OBC)flight computer of the TT&C subsystem“The TT&C subsystem consists of the bus computer (the on-board computer or OBC)” | Not said | — | — |
| Uplink/downlink unit, remote interface units, deployment device control, event detectorscommand and telemetry path with the GPS Operational Control Segment“remote interface units, deployment device control, and event detectors” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Liquid apogee engine (LAE)final orbit insertion; raises the satellite from launch orbit to its operational slot“the liquid apogee engine for final orbit insertion” | Not said | — | — |
| 5-lbf thrusterslarge on-orbit maneuvers“the 5-lbf thrusters for large on-orbit maneuvers” | Not said | — | — |
| 0.2-lbf thrustersattitude control and station keeping“0.2-lbf thrusters for more coarse maneuvers including periodic station keeping” | Not said | — | — |
| Propellant and pressurant tankscomposite tanks for the propulsion subsystem“The propellant and pressurant tanks are manufactured by Orbital ATK from lightweight, high-strength composite materials.” | composite (type not stated)fibre-reinforced-polymer-composite | — | Supplier: Orbital ATK (now Northrop Grumman) |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Lockheed Martin A2100 bus structurebasic satellite structure, hinges and frangibolts for deployable elements“The MSS consists of the basic SV structure, hinges, and the frangibolts for deployable elements.” | Not said | — | Supplier: Lockheed Martin |
| Frangibolts and hingesrelease and hinge the deployable elements“The MSS consists of the basic SV structure, hinges, and the frangibolts for deployable elements.” | Not said | — | — |
No structural, panel, solar-cell, thermal-blanket or tank material is stated in the Lockheed Martin or InsideGNSS pages read. The InsideGNSS article (2011, design stage) names nickel-hydrogen batteries but later says lithium-ion batteries will reduce weight, so the flight battery chemistry is unconfirmed. SV01 mass comes from a secondary source (Wikipedia) and was not matched to a Lockheed or Space Force document. More detail: Not published on the pages read: solar cell type and array maker, the flight battery chemistry (the 2011 article says nickel-hydrogen then lithium-ion for later builds; Wikipedia says nickel-hydrogen), reaction wheel, IMU, sun sensor and thruster makers, the liquid apogee engine model and maker, the bus panel and tank liner materials, thermal blanket film types, antenna element materials, and the makers of the bus computer and uplink/downlink unit. The subsystem list is from a 2011 design-stage article, so the flight hardware may differ. The 2010 SpaceNews page that Wikipedia cites for the Orbital ATK tanks no longer loads, so the tank and JIB antenna statements rest on Wikipedia. Per the sources read, GPS III flew on Falcon 9 (SV01, SV03 to SV10) and on a Delta IV (SV02); no GPS III launch on Vulcan was found. The Delta IV Medium+ (4,2) engines and the Falcon 9 second-stage Merlin Vacuum engine were not sourced here. More detail: Not published on the pages read: solar cell type and array maker, the flight battery chemistry (the 2011 article says nickel-hydrogen then lithium-ion for later builds; Wikipedia says nickel-hydrogen), reaction wheel, IMU, sun sensor and thruster makers, the liquid apogee engine model and maker, the bus panel and tank liner materials, thermal blanket film types, antenna element materials, and the makers of the bus computer and uplink/downlink unit. The subsystem list is from a 2011 design-stage article, so the flight hardware may differ. The 2010 SpaceNews page that Wikipedia cites for the Orbital ATK tanks no longer loads, so the tank and JIB antenna statements rest on Wikipedia. Per the sources read, GPS III flew on Falcon 9 (SV01, SV03 to SV10) and on a Delta IV (SV02); no GPS III launch on Vulcan was found. The Delta IV Medium+ (4,2) engines and the Falcon 9 second-stage Merlin Vacuum engine were not sourced here.
Maker credit: Lockheed Martin (navigation payload by ITT). Collected from public pages and documents, checked 4 Nov 2026.
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