Screenshot of GPS III SV06 from SpaceX webcast. The early bird got the second worm so to speak
Mission Rundown: SpaceX Falcon 9 - GPS III SV06
Written: January 18, 2023
Took a while to launch more stuff
SpaceX is being commissioned by the US Space Force to launch the sixth Third Generation Global Positioning System (GPS) satellite into a medium-Earth orbit.
The Falcon 9 will lift off from Space Launch Complex 40 (SLC-40), at the Cape Canaveral Space Force Station, in Florida, USA. As the name implies, this launch will mark the sixth launch of a GPS block III satellite to date.
Notam map of the launch corridor. The ASDS A Shortfall Of Gravitas is waiting 637 km downrange
Like all GPS Block III the SV06 satellite is nicknamed after a historically significant figure; in this case the female aviator Amelia Earhart.
B1077-2 will have made its second flight after launching its next mission:
SpaceX Falcon 9 rocket B1077-2 will launch the GPS Block III SV06 satellite for the US Space Force. SV06 is part of the United States Space Force’s new generation GPS constellation. It is launching on Wednesday January 18, at 07:00:00 EST, from Space Launch Complex-40 - SLC-40 at Cape Canaveral Space Force Station - CCSFS.
Booster B1077-2 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 SV06 in its fairing.
SpaceX will also recover both fairing halves in the Atlantic Ocean with the recovery vessel Doug, named after Demo-2 Astronaut Doug Hurley.
SpaceX is the first entity ever that recovers and reflies its fairings. 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 drogue chutes and parafoils to help them glide down to a soft landing for recovery.
Lately it’s apparent that the fairings are actively being aiming for the droneship in order to speed up the recovery process and cut corners of the time table. The fairing is actively breaking its speed and turning back before deploying its parachute at the last moment. It’s not clear whether or not the cold gas nitrogen thrusters are capable of doing a boost back ‘push’ so the fairings stop their forward momentum mid flight.
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.
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.
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 to prevent saltwater from the ocean from flooding and sinking the fairing, and makes refurbishment toward the next flight easier.
Falcon fairings halfs have been recovered and reused since 2019. Improved design changes and overall refurbishment procedures have decreased the effects of water landings and led to an increased recovery rate of fairings.
The fairings are a used pair from three and four previous missions with no known joint mission. Both fairings are expected to survive the landing. Active fairings are equipped with four pushrods to separate the two fairing halfs.
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.
The newest consists of 5 operational GPS Block IIIs launched from 2018 to 2021.
There are 12 operational GPS Block IIF follow-ons, which launched from 2010-2016.
Next is 7 operational GPS Block IIR-M modernizes; they launched from 2005-2009.
Finally, there are 7 operational Block IIR replenishments, launched between 1997 and 2004.
There may be one less old satellite soon. 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. Accuracy depends on the number of decimals given your GPS receiver from the clocks on the GPS satellites regardless of age.
The GPS III SV06 payload
Assumed to be given the military designation USA-343, GPS-III SV06 or Amelia Earhart, is an United States navigation satellite which forms part of the Global Positioning System. It was the sixth GPS Block III satellite to be launched.
USA-343 was launched by SpaceX on January 18, 2023 at 12:24 UTC atop Falcon 9 booster B1077-2. The launch took place from SLC-40 of the Cape Canaveral Air Force Station, and placed USA-343 directly into semi-synchronous orbit. About eight minutes after launch, Falcon 9 B1077-2 successfully landed on A Shortfall of Gravitas.
As of 2023, USA-343 will be 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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