SpaceX Falcon 9 Block 5 - GPS III SV05 - Launched June 17, 2021
Screenshot of GPS III SV05 from SpaceX webcast
Mission Rundown: SpaceX Falcon 9 B5 - GPS III SV05
Written: July 28, 2021
Finally approved to launch military stuff.
SpaceX is being commissioned by the US Air Force to launch the first Third Generation Global Positioning System (GPS) satellite to orbit. This was originally planned as the second GPS launch with ULA launching the first. The US Air Force changed the order of launches because SpaceX sued the US Government to get the launch contract in a bidding war with ULA, who had won a 36 launch-block without competitive bidding from SpaceX.
After the lawsuit was dropped, the Air Force followed through on its promise and publicly requested fixed-price contract bids for the launch of the second GPS III satellite. The competitive bid was submitted as part of the Air Force’s Evolved Expendable Launch Vehicle (EELV) program – the “Expendable” part of which being a holdover from the era of full expendability of rockets. The Falcon 9 can fly “bareback” without legs and gridfins, thus it is regarded as an expendable part of the EELV program even though it is capable of being recovered and reused.
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 the booster to launch again.
SpaceX Falcon 9 rocket B1062-2 will launch the GPS Block III SV05 satellite for the American military. SV05 is part of the United States Space Force’s new generation GPS constellation. It is launching on Thursday July 17, at 12:09:35 EST, from Space Launch Complex-40 (SLC-40) at the Cape Canaveral Space Force Station (CCSFS).
Booster B1062-2 completed a static fire test 15:30 EDT at SLC-40 on June 12 without a payload. It was later rolled back to be mated with GPS III SV05 in its fairing.
SpaceX is the first entity ever that recovers and reflies its fairings. A leased recovery vessel HOS Briarwood will most likely salvage the fairing halves.
After being jettisoned, the two fairing halves will use cold gas thrusters to orientate themselves as they descend through the atmosphere. Once at a lower altitude, they will deploy parafoils to help them glide down to a soft landing for recovery.
Comparison of Type 1 and 2 with measurements based on pixels - Type 2 are 5-6 inches thicker
There are three known types of 34 x 17 foot fairings used by SpaceX to protect payload during ascent through the atmosphere. The first type had 10 evenly spaced ventilation ports in a circle on the bottom part of the fairings. This type was not aerodynamic enough to carry a parachute and ACS - Attitude Control System.
The aerodynamic balance during descent must have made them prone to stalling, or they burned up too easily. ACS gas tanks, flight orientation computers and ACS thrusters must have helped with these problems during development of type 2 fairings.
The second type is a slightly thicker fairing with only 8 evenly spaced ventilation ports in a circle on the bottom part of the fairings. The ventilation ports release the pressurized Nitrox gas during ascent, but let seawater in which makes it harder to refurbish the fairings after recovery from the ocean.
The new third type has 8 ventilation ports in pair’s near the edge of the fairings. Some old type 2 fairings have been rebuilt and reused in Starlink launches. That have been a test program to develop the type 3 fairings.
Material usages and building techniques may also vary in all fairing models. Acoustic tiles are not used for protection of Starlink V1.0 satellites but are used with fragile payloads.
A fairing half is basically built like a boat hull without keel and ribs, which makes it wobbly and flimsy because it can flex ± a meter during fairing separation. SpaceX must have a blooper reel of recordings from the early type 1 days.
GPS satellite constellation
GPS, or Global Positioning System, is a medium-Earth orbit satellite constellation which is operated by the United States Space Force. It is America’s global navigation satellite system, providing worldwide coverage for geolocation and time. Currently, there are 31 active GPS satellites in orbit, with an additional 25 planned.
Out of those 31 active satellites, there are four different models, and two different blocks. From newest to oldest there are two operational GPS Block IIIs, which were launched in 2018 and 2019. There are also 12 operational GPS Block IIFs, which launched from 2010-2016. Next, 7 operational GPS Block IIR-Ms; they launched from 2005-2009. Finally, there are 10 operational Block IIRs, launched between 1997 and 2004. Learn more about the block versions here.
The GPS constellation brings impressively accurate readings to the civilian population, with even more accuracy for the branches of the military. For the civilian population, GPS provides an impressive 500-30 cm of accuracy. This is especially impressive as each satellite is a circular orbit with an orbital height of 20,180 km. GPS Block III plans to improve on this even further.
The payload
Under the military designation USA-319, also known as GPS-III SV05 or Neil Armstrong, is an United States navigation satellite which forms part of the Global Positioning System. It was the fifth GPS Block III satellite to be launched.
USA-319 was launched by SpaceX on 17 June 2021 at 16:09 UTC atop Falcon 9 booster B1062-2. The launch took place from SLC-40 of the Cape Canaveral Air Force Station, and placed USA-319 directly into semi-synchronous orbit. About eight minutes after launch, Falcon 9 B1062-2 successfully landed on Just Read the Instructions.
As of 2021, USA-319 was in a 54.9 degree inclination orbit with a perigee of 20,181 kilometers (12,540 mi) and an apogee of 20,198 km (12,550 mi).
GPS Block III is the third major iteration of the GPS satellite. Each satellite was designed and manufactured by Lockheed Martin. Each satellite is designed to have a 15 year lifespan, but based on previous blocks lasting over twice as long as their lifespan, each satellite will likely last longer.
The goal of GPS Block III was to provide enhanced signal reliability, accuracy, and integrity. The satellites will build upon, or improve, features included on the Block IIR-M and IIF satellites are including:
L1C signal on the 1575.42 MHz L1 frequency
L2C signal on the 1227.6 MHz L2 frequency
L5 “Safety of Life” signal on the 1176.45 MHz L5 frequency
The first satellite was supposed to launch in 2014, but experienced many delays that pushed the first launch back to December 2018. The 10th, and final, GPS Block III satellite is expected to launch NET Q2 2023.
Under the build contract, Lockheed Martin served as prime manufacturer and provided the A2100 bus structure for the satellites. Additionally, Orbital ATK, now Northrop Grumman Innovation Systems, provided the propellant tanks, the pressure tanks and the propulsion jets, and Northrop Grumman Astro Aerospace provided the eight deployable JIB antennas.
Under the administration of President Barack Obama, the Next Generation GPS Operational Control System contract was awarded to Raytheon on 25 February 2010 to build the ground control system for the GPS III satellites.
The first GPS III satellite was originally to launch in 2014, And was scheduled to be taken to orbit aboard a United Launch Alliance (ULA) Delta IV M+ rocket, but delays due to late technology, late build deliveries and lawsuits pushed the launch into december 2018.
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