Featured image credit: SpaceX
Lift Off Time
(Subject to change)
November 08, 2022 – 16:06 UTC | 11:06 EST
Mission Name
Galaxy 31 & 32, two telecommunication satellites
Launch Provider
(What rocket company is launching it?)
SpaceX
Customer
(Who’s paying for this?)
Intelsat
Rocket
Falcon 9 Block 5, B1051-14; 114.07 day turnaround time
Launch Location
Space Launch Complex 40, Cape Canaveral Space Force Station, Florida, USA
Payload mass
Unknown, ~3,500 kg each
Where are the satellites going?
Geostationary Transfer Orbit (GTO)
Will they be attempting to recover the first stage?
No
Where will the first stage land?
B1051 will splash down in the Pacific Ocean
Will they be attempting to recover the fairings?
The fairing halves will be recovered from the water ~760 km downrange by Bob
Are these fairings new?
TBD
How’s the weather looking?
The weather is currently 30% GO for launch (as of November 5, 12:30 UTC)
This will be the:
– 185th Falcon 9 launch
– 122nd Falcon 9 flight with a flight-proven booster
– 126th re-flight of a booster
– 48th re-flight of a booster in 2022
– 52nd launch for SpaceX in 2022 (a record)
– 103rd SpaceX launch from SLC-40
– 155th orbital launch attempt of 2022
Where to watch
Official Livestream
What’s This All Mean?
SpaceX is set to launch two communication satellites to geostationary transfer orbit (GTO) for Intelsat. The Galaxy 31 & 32 satellites will be launched from SpaceX’s launch pad Space Launch Complex 40, at the Cape Canaveral Space Force Station, in Florida, USA. Following deployment from the second stage, the satellites will spend the coming months raising their orbits to their operational orbit in geostationary Earth orbit (GEO). It is expected that the satellites will be operational by November 2022.
What are the Galaxy 31 & 32 satellites?
The Galaxy 31 & 32 satellites are replacements for Intelsat’s aging satellites in GEO slots above America. Each of these satellites is a C-band-only communication satellite, allowing the satellites to service North America with television broadcasting.
The satellites are thought to be based on the GEOStar-3 satellite Bus and is equipped with the IHI BT-4 propulsion module. Built by the Japanese company IHI aerospace, the BT-4 is a pressure-fed engine that runs on N2O4 and Hydrazine. It produces 500 N of thrust in a vacuum with an ISP of ~320 seconds. This engine is also used on Cygnus and HTV — two ISS resupply vehicles.
These satellites are a part of Intelsat order of six new satellites: four of which will be built by Maxar Technologies and two which will be built by Northrop Grumman. If all of these satellites are operational by December 5, 2023, Intelsat will receive $4.87 billion from the Federal Communication Commission (FCC) in the FCC’s attempts to clear the 300 MHz spectrum, which is used in cellular 5G networks.
The satellites have an expected lifespan of 15 years, and they are powered by two deployable solar arrays and batteries. While neither Intelsat or Maxar have released the mass of the satellite, it is expected that the satellite masses roughly 3,500 kg based on previous satellites and the Falcon 9’s performance.
What Is Falcon 9 Block 5?
The Falcon 9 Block 5 is SpaceX’s partially reusable two-stage medium-lift launch vehicle. The vehicle consists of a reusable first stage, an expendable second stage, and, when in payload configuration, a pair of reusable fairing halves.
First Stage
The Falcon 9 first stage contains nine Merlin 1D+ sea level engines. Each engine uses an open gas generator cycle and runs on RP-1 and liquid oxygen (LOx). Each engine produces 845 kN of thrust at sea level, with a specific impulse (ISP) of 285 seconds, and 934 kN in a vacuum with an ISP of 313 seconds. Due to the powerful nature of the engine, and the large amount of them, the Falcon 9 first stage is able to lose an engine right off the pad, or up to two later in flight, and be able to successfully place the payload into orbit.
The Merlin engines are ignited by triethylaluminum and triethylborane (TEA-TEB), which instantaneously burst into flames when mixed in the presence of oxygen. During static fire and launch the TEA-TEB is provided by the ground service equipment. However, as the Falcon 9 first stage is able to propulsively land, three of the Merlin engines (E1, E5, and E9) contain TEA-TEB canisters to relight for the boost back, reentry, and landing burns.
Second Stage
The Falcon 9 second stage is the only expendable part of the Falcon 9. It contains a singular MVacD engine that produces 992 kN of thrust and an ISP of 348 seconds. The second stage is capable of doing several burns, allowing the Falcon 9 to put payloads in several different orbits.
For missions with many burns and/or long coasts between burns, the second stage is able to be equipped with a mission extension package. When the second stage has this package it has a grey strip, which helps keep the RP-1 warm, an increased number of composite-overwrapped pressure vessels (COPVs) for pressurization control, and additional TEA-TEB.
Falcon 9 Booster
The booster supporting the Galaxy 31 & 32 mission is B1051, which has supported thirteen previous flights. Hence, its designation for this mission is B1051-14.
B1051’s missionsLaunch Date (UTC)Turnaround Time (Days)SpaceX Demonstration Mission-1March 2, 2019 07:49N/ARADARSAT ConstellationJune 12, 2019 14:17102.27Starlink V1.0 L3January 29, 2020 14:06230.99Starlink V1.0 L6April 22, 2020 19:3084.22Starlink V1.0 L9August 7, 2020 05:12106.40Starlink V1.0 L13October 18, 2020 12:2572.30SXM-7December 13, 2020 17:3056.21Starlink V1.0 L16January 20, 2021 13:0237.81Starlink V1.0 L21March 14, 2021 10:0152.87Starlink V1.0 L27May 9, 2021 06:4255.86Starlink Group 4-4December 18, 2021 12:41223.25Starlink Group 4-12March 19, 2022 04:4290.67Starlink Group 4-22July 17, 2022 14:20120.40Galaxy 31 & 32November 7, 2022 16:06114.07
Falcon 9 Fairings
The Falcon 9’s fairing consists of two dissimilar reusable halves. The first half (the half that faces away from the transport erector) is called the active half, and houses the pneumatics for the separation system. The other fairing half is called the passive half. As the name implies, this half plays a purely passive role in the fairing separation process, as it relies on the pneumatics from the active half.
Both fairing halves are equipped with cold gas thrusters and a parafoil which are used to softly touch down the fairing half in the ocean. SpaceX used to attempt to catch the fairing halves, however, at the end of 2020 this program was canceled due to safety risks and a low success rate. On Galaxy 31 & 32, SpaceX will attempt to recover the fairing halves from the water with their recovery vessel Bob.
In 2021, SpaceX started flying a new version of the Falcon 9 fairing. The new “upgraded” version has vents only at the top of each fairing half, by the gap between the halves, whereas the old version had vents placed spread equidistantly around the base of the fairing. Moving the vents decreases the chance of water getting into the fairing, making the chance of a successful scoop significantly higher.
An active Falcon 9 fairing half (Credit: Greg Scott)
Falcon 9 passive fairing half (Credit: Greg Scott)
Half of the fairing being taken off Go. Navigator. (Credit: Lupi)
A passive fairing half being unloaded from Shelia Bordelon after the Starlink V1.0 L22 mission (Credit: Kyle M)
Galaxy 31 & 32 Countdown
All times are approximate
HR/MIN/SECEVENT00:38:00SpaceX Launch Director verifies go for propellant load00:35:00RP-1 (rocket grade kerosene) loading underway00:35:001st stage LOX (liquid oxygen) loading underway00:16:002nd stage LOX loading underway00:07:00Falcon 9 begins engine chill prior to launch00:01:00Command flight computer to begin final prelaunch checks00:01:00Propellant tank pressurization to flight pressure begins00:00:45SpaceX Launch Director verifies go for launch00:00:03Engine controller commands engine ignition sequence to start00:00:00Falcon 9 liftoff
Galaxy 31 & 32 Launch, Landing, And Deployment
All times are approximate
HR/MIN/SECEVENT00:01:12Max Q (moment of peak mechanical stress on the rocket)00:02:331st stage main engine cutoff (MECO)00:02:371st and 2nd stages separate00:03:25Fairing deployment00:06:271st stage entry burn begins00:06:481st stage entry burn completes00:08:152nd stage engine cutoff (SECO)00:08:181st stage landing burn begins00:08:401st stage landing00:26:192nd stage engine restarts (SES-2)00:27:062nd stage engine cutoff (SECO-2)00:32:57Galaxy 33 deploys00:38:07Galaxy 34 deploys
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