SpaceX has launched another next-generation Global Positioning System (GPS) satellite for the United States Space Force. Falcon 9 lifted off with the GPS-III-SV05 satellite on June 17 from SLC-40 at the Cape Canaveral Space Force Station in Florida right on time at 12:09EDT (16:09 UTC).
This was the 19th Falcon 9 launch in 2021, and GPS-III-SV05 is the company’s fourth overall mission for the GPS program and the first to use a flight-proven first stage booster.
Space Launch Delta 45 had predicted a 70% chance of acceptable weather conditions for launch on June 17 as well as for the backup opportunity 24 hours later.
At 3:30 PM EDT on June 12, SpaceX completed a successful static fire of Falcon 9’s first stage booster, B1062-2. After the test, the first stage and attached second stage were rolled back into the hangar at SLC-40 to be mated to the encapsulated GPS-III-SV05 spacecraft, before returning to the pad prior to launch.
On the afternoon of June 13, tug Finn Falgout departed Port Canaveral with drone ship Just Read the Instructions in tow. On June 16, the two ships arrived at the landing zone about 642 kilometers downrange from the launch site. GO Quest, the drone ship support vessel, also arrived near the recovery zone shortly after.
For this mission, a new vessel joined SpaceX’s oceangoing recovery fleet. HOS Briarwood will recover Falcon 9’s payload fairing halves after they splash down in the Atlantic Ocean.
Similar in size to Shelia Bordelon, the previous temporary fairing recovery vessel, HOS Briarwood can be booked as a “flotel” and features an enormous crane, along with seemingly just enough deck space to support two recovered fairing halves.
Space Force Advancing Reusability
Falcon 9 booster B1062-2 supported this mission. The first stage previously launched GPS-III-SV04, the previous GPS mission, in November 2020.
Prior to the GPS-III-SV04 launch, SpaceX announced that the US Space Force would allow the company to recover and reuse Falcon 9 boosters on national security missions, which includes the GPS program.
In order to certify SpaceX’s recovery and reuse process, B1062 was specifically reserved for GPS-III-SV05. After returning to port following the GPS-III-SV04 mission, the Space Force conducted a lengthy review of the booster and SpaceX’s refurbishment procedures, before finally clearing it to launch.
Last year, SpaceX was also awarded a “fleet surveillance” contract from the Space Force, which gives the branch insight into all of SpaceX’s non-military launches. The agreement was then expanded after the company won the NSSL Phase 2 launch contract in August.
Going forward, SpaceX will be able to fly other boosters on national security missions, not just ones that previously flew government payloads.
The GPS-III-SV05 satellite is the fifth of 10 spacecraft in the third generation of GPS satellites. This generation includes improvements such as more accurate precise location tracking and time referencing.
The aging second generation of GPS satellites were launched from 1989 to 2016. Soon the GPS-III and GPS-III Follow-On satellites will replace some of the older satellites before replacing the second generation entirely.
The GPS-II generation of satellites were built by Rockwell, then by Boeing, as well as Lockheed Martin. This time around, the GPS-III satellites are based on Lockheed Martin’s A2100 modernized (A2100M) satellite bus.
A2100M is Lockheed Martin’s Medium Earth Orbit and Geostationary Orbit satellite bus offering. First launched in 1996, this bus has been used for many military and commercial satellites including the SBIRS-GEO satellites, the Arabsat 6A telecommunications satellite, and the Advanced Extremely High Frequency military satellite constellation.
A more modern version of the A2100, known as the A2100M (modernized), will be used for the GPS-III Follow-On. These satellites will provide even more accurate location tracking and time referencing, but the satellites are also designed to be serviceable on orbit. This can allow the satellites to be upgraded over time. 22 of these satellites will launch starting in 2026.
In 2008, Lockheed Martin won the contract for the GPS-III satellites. The first GPS-III satellite launched on an expendable Falcon 9 in December 2018. The second GPS-III satellite was launched on the final Delta IV Medium in August 2019.
This was followed by the third and fourth GPS-III satellites on Falcon 9 in 2020. GPS-III-SV03 was launched by Falcon 9 booster B1060 in June 2020. GPS-III-SV04 was launched by Falcon 9 booster B1062, the same booster to launch the GPS-III-SV05 satellite.
GPS-III-SV05 weighs approximately 4,331 kilograms, the same as GPS-III-SV03 and GPS-III-SV04. Every GPS-III satellite is equipped with a single LEROS-1 apogee propulsion system as well as twin solar arrays for electrical power.
The navigation payload for the satellite is provided by L3Harris Technologies. Both GPS-III and GPS-III Follow-On will have a lifetime of 15+ years.
GPS-III-SV05 was completed during Q1 of 2021 at the Lockheed Martin A2100 production facility in Waterton, Colorado. On April 6, it was transported to Florida by a C-17 Globemaster transport aircraft. There it was taken to the Astrotech Space Operations facility to begin final preparations, which included final testing and fueling of the satellite.
After fueling, the satellite was then encapsulated inside Falcon 9’s 5.2 meter diameter payload fairing.
As the countdown clock reached T0, Falcon 9 lifted off and began pitching downrange towards the northeast, targeting a 55 degree inclined orbit.
Liftoff of Falcon 9 delivering #GPSIIISV05 to orbit. It was a beautiful day for a launch (and landing) after several days of rain on the coast.@NASASpaceflight mission recap:https://t.co/wpolxu6ixA pic.twitter.com/I3Lb3ounsR
— Julia Bergeron (@julia_bergeron) June 17, 2021
At T+2:32, B1062’s nine Merlin engines shut down, followed shortly by stage separation and second stage ignition.
Falcon 9’s payload fairings then separated at T+3:47, exposing GPS-III SV05 to space. The second stage’s Merlin vacuum engine then shut down at T+8:07, placing the satellite into a parking orbit.
After doing its job, booster B1062 touched down on the deck of Just Read the Instructions roughly 8 minutes and 30 seconds after launch.
At T+1:03:35, the second stage ignited for a second and final time to place the payload into a Medium Earth transfer orbit. GPS-III-SV05 was then deployed at T+1:29:20 and will eventually use its own propulsion to circularize its orbit.
SpaceX has one more mission planned for June, Falcon 9 B1060-8 launching from SLC-40 with the Transporter-2 rideshare mission. Meanwhile, the drone ship Of Course I Still Love You is currently en route to the west coast via the Panama Canal to support a launch manifest at Vandenberg Space Force Base in California.
(Lead image: Falcon 9 launch GPS III SV05. Credit: Stephen Marr for NSF L2)