SpaceX Falcon 9 Block 5 - Nilesat-301 - Launched June 8, 2022
Screenshot from SpaceX Webcast of the launch of Nilesat-301
Mission Rundown: SpaceX Falcon 9 B5 - Nilesat-301
Written: August 9, 2022
Ahh.. - It’s GTO - We finally meet again
Wednesday, June 8 at 5:04 p.m. ET, SpaceX launched a Falcon 9 with Nilesat 301 to a geosynchronous transfer orbit from Space Launch Complex 40 (SLC-40) at Cape Canaveral Space Force Station in Florida.
Falcon 9 followed an eastward trajectory for this mission, like all other GTO flights. Geostationary orbits have a zero-degree inclination relative to the equator, so SpaceX wants to send Falcon 9 directly east so as not to create any additional orbital inclination than the natural 28.6 degrees — the lowest possible inclination — achieved by going due east from the Cape during the initial ascent to orbit.
Just over one minute into the flight, the vehicle passed through Max-Q, the moment of maximum aerodynamic pressure on the vehicle. As the name suggests, this is often one of the harshest moments of the ascent. To deal with the stresses, the first stage engines are throttled down momentarily for this period of flight.
Approximately two and a half minutes after liftoff, the first stage engines shut down in a process called Main Engine Cutoff (MECO). The two stages separated 4 seconds later, followed by the ignition of the second stage’s Merlin Vacuum engine 7 seconds later. Finally, the fairing will separate nearly a minute later.
The second stage completed its first burn: an event that is designated Second Stage Engine Cutoff (SECO-1). After this, the stage coasted for a period of time before restarting its engine for an approximately one-minute burn, sending itself and the payload into a supersynchronous geostationary transfer orbit. The satellite will separate from the stage after this burn, beginning its months-long orbit raising and commissioning campaign.
The two fairing halves stabilized their fall back to earth, bore the brunt of the reentry heat into the atmosphere, and parachuted into the Atlantic Ocean for recovery.
SpaceX will also recover both fairing halves in the Atlantic Ocean with the recovery vessel Bob, named after Demo-2 Astronaut Bob Behnken.
B1062-7 will have made its seventh flight after launching the following mission:
B1062-7 didn’t perform a static fire test after refurbishment and waiting for an east coast launch out of the Cape. SpaceX has since Starlink V1.0 L08 omitted this safety precaution many times so far. It is not required to perform a static fire test inhouse missions like Starlink, that was to save money and time before the launch.
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.
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 new pair from no previous mission. Both fairings survived the landing. Active fairings are equipped with four pushrods to separate the two fairing halfs.
Fairings had evenly spaced venting ports that have been redesigned a number of times by having first ten, then eight and now having their venting ports built as close pairs along the fairing edge. This prevents saltwater from the ocean from flooding and sinking the fairing, and makes refurbishment toward the next flight easier.
The Payload
The single satellite payload on this mission is Nilesat-301, a multi-purpose broadcasting satellite owned and operated by the Egyptian company Nilesat.
The 4,100-kilogram spacecraft was built by Thales Alenia Space in France and is based on their Spacebus 4000B2 satellite bus. Attached to this bus are 32 Ku-band transponders and 6 Ka-band transponders. These are powered by two large deployable solar arrays, and batteries to hold power through the orbital night.
The satellite will operate in a geostationary orbit, occupying a slot at 7° West. From there, it will deliver television, radio, and internet to customers across North Africa and the Middle East. While it will be available to urban users, the internet service has a large focus on commercial and industrial use, such as in remote oil fields.
It will deliver 6 Ka-band (26.5–40 gigahertz – portions of the 5G network operate in this frequency range) coverage to all of Egypt and 32 Ku-band (12 to 18 gigahertz – most commonly used by communications satellites, by NASA for ISS and Tracking and Data Relay Satellite communications, by SpaceX for Starlink frequencies, and by law enforcement for radar traffic speed measurements) to the rest of its aforementioned service area.
The new satellite is expected to have a service life of over 15 years, which will begin once it raises itself into geostationary orbit and Thales Alenia Space completes all of its checkouts and tests of the craft.
Thales Alenia Space have built the Nilesat-301 satellite as a follow up to the Nilesat-101, Nilesat-102, Nilesat-103, and Nilesat-201 satellites. This geostationary satellite constellation provides television, radio, and data transmission to Northern Africa and the Middle East. Nilesat-301 will replace the aging Nilesat-201 satellite, which was launched in 2010 atop an Ariane 5.
Nilesat-301 is equipped with an S400 engine which runs on monomethylhydrazine and dinitrogen tetroxide. The S400 creates ~420 newtons of thrust in a vacuum with a specific impulse of 3,150 m/s (321 seconds).
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