Photo from SpaceX of the Amazonas Nexus waiting to launch standing patiently under the Moon
Mission Rundown: SpaceX F9 - Amazonas Nexus
Written: February 7, 2023
Watching TV in South America
SpaceX has launched the Amazonas Nexus satellite for Hispasat on a Falcon 9 rocket for the 111th time from SLC-40 at the Cape Canaveral Space Force Station. Liftoff occurred at 20:32 EST on Monday evening, February 6, 2023 - 01:32 UTC on Tuesday, February 7, 2023 - under extremely favorable weather conditions.
Amazonas Nexus will provide TV and internet communications for all of the Americas — including Greenland as well as maritime shipping corridors — and marks the first time an Amazonas satellite was launched on a Falcon 9.
From the NOTAM notice. It seems that Just Read The Instruction is located 621 km downrange
The booster launched from SLC-40 is B1073-6. It landed on the drone ship Just Read The Instruction, 621 km east of the launch site, roughly eight and half minutes after liftoff.
After boosting the second stage along with its payload towards orbit, the first stage will freefall in a parabolic curve before it performs a 19 second re-entry burn meant to slow the vehicle down before the atmospheric reentry. The booster will then perform a 23 second landing burn and softly land aboard SpaceX’s autonomous spaceport drone ship.
B1073-6 will have made its sixth flight after launching its next mission:
Booster B1073-6 didn’t perform or complete 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 its payload and fairing.
SpaceX is the first entity ever that recovers and reflies its fairings. The recovery vessel Bob - named after Astronaut Bob Behnken - will salvage the fairing halves.
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.
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.
The fairings are a used pair from four and five 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.
Not relevant for this flight. 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 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.
Material usages and building techniques may also vary in all fairing models. Acoustic tiles are not used for protection of Starlink 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 ± more than a meter during fairing separation. SpaceX must have a blooper reel of recordings from the early type 1 days.
The mission payload
Amazonas Nexus will provide TV and internet communications for all of the Americas — including Greenland as well as maritime shipping corridors — and marks the first time an Amazonas satellite was launched on a Falcon 9. Previous missions flew on either Ariane 5 or Proton-M rockets out of the Centre Spatial Guyanais (CSG) in French Guiana.
The 4,500 kg satellite was launched into a geostationary transfer orbit (GTO) and will now maneuver itself into a geostationary orbit (GEO) at the 61 degrees West GEO slot.
The Amazonas Nexus spacecraft is owned and operated by the Spanish communications company Hispasat. Formed in 1989, the company has already launched 13 satellites and currently transmits over 1,250 television channels and radio stations to more than 30 million customers.
Amazonas Nexus will join the overall fleet as a high throughput satellite, which means it utilizes - transmit data on the Ku and Ka bands simultaneously. As a result, it can handle more data compared to other spacecraft operating in the same spectrum.
Another significant development is its Digital Transparent Processor, which allows Hispasat to make operational changes on orbit and adapt to the needs of different markets and customers based on what data is needed.
Graphic image moving over the North American continent toward the North Atlantic and Greenland
Amazonas Nexus joins five other Amazonas satellites in orbit and is designed to replace Amazonas 2, which launched aboard an Ariane 5 in 2009. All Amazonas satellites are located at either 36 degrees West or 61 degrees West.
Specifically, Amazonas Nexus will provide coverage for all of North and South America, the North and South Atlantic Ocean corridors, and Greenland. The main target is to connect companies in remote areas, on the water, and in the air.
The satellite was built by Thales Alenia Space, a joint venture between Thales and Leonardo in Europe. The company had previously built two satellites for Hispasat, including Hispasat 1C and 1D.
Amazonas Nexus was built on a Spacebus NEO platform that uses electric propulsion in form of Hall effect thrusters, provides 20 kW of spacecraft power via two deployable solar arrays, and has an expected lifespan of 15 years.
While integrated by Thales Alenia Space, Spacebus NEO was developed under a European Space Agency (ESA) Partnership Project managed jointly by ESA and the French Space Agency CNES.
The rocket launch
The mission followed a traditional Falcon 9 countdown. At T-35 minutes before liftoff, equipment at the launch pad began to load both stages of Falcon 9 with RP-1 fuel, a type of refined kerosene. At the same time, liquid oxygen (LOX), the oxidizer for the Falcon fleet of rockets, began loading into the first stage.
At T-1 minute, Falcon 9 entered “startup,” meaning the onboard computers have full control of the countdown as the propellant tanks are pressurized for flight.
At T-3 seconds, the command was given to ignite the nine Merlin 1D# engines at the base of the first stage, leading to liftoff at T0.
A little over a minute into the flight, Falcon 9 experienced the maximum dynamic pressure on the vehicle, known as Max-Q.
Almost two and a half minutes into the mission, a series of events happened in quick succession. The first stage engines experienced main engine cutoff (MECO), followed four seconds later by separation of the first and second stages. About seven seconds after that, the second stage engine started.
Three and a half minutes into the flight, the fairing halves separated and began their journey back towards the Atlantic Ocean for recovery so they can be used again on an upcoming flight.
The first stage then performed two burns, with the second gently landing the vehicle on top of Just Read the Instructions in the Atlantic Ocean nearly eight and a half minutes after taking off.
Meanwhile, the Merlin Vacuum engine performed a second stage engine cutoff, or SECO-1, a little more than eight minutes and 10 seconds into the mission.
The second stage lit its engine once more at T+26 minutes 41 seconds for a burn lasting just over a minute that raised the orbit’s apogee to the desired altitude for the mission.
Thirty-five minutes after launch, Hispasat’s Amazonas Nexus was deployed into its target elliptical Geostationary Transfer Orbit - GTO - from where Hispasat’s Amazonas Nexus will find its own way to its allotted geostationary slot.
The Falcon 9 rocket
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 17x34 feet reusable fairing halves.
The Falcon 9 first stage contains 9 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 their thrust increases to 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.
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.
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 ignitions - 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. This package consists of a gray paint strip, which helps keep the RP-1 tank warm, and extra composite overwrapped pressure vessels (COPVs) for pressurization control, and additional TEA-TEB.
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