ViaSat-3 Americas launches on expendable Falcon Heavy

by Justin Davenport

Falcon Heavy’s second launch 2023 set sail on Sunday, with liftoff with the ViaSat-3 Americas satellite as the main payload, plus the much smaller Arcturus and G-Space 1 rideshare satellites. 

Liftoff was scheduled for Wednesday, April 26, at 8:26 PM EDT (00:26 UTC on Monday) at the start of a 57-minute window. However, SpaceX has since delayed it to Friday following bad weather during Thursday’s window. The launch was then moved to Friday, before scrubbing with under a minute to launch from Launch Complex 39A at the Kennedy Space Center in Florida. The latest attempt on Sunday was successful.

This flight — the sixth overall for Falcon Heavy — had been scheduled for April 18 but was delayed after its preflight static fire. The firing was not nominal and revealed at least one undisclosed issue with the vehicle that needed to be corrected in the hangar. Accordingly, SpaceX replaced two engines on Falcon Heavy’s first stage.

The Falcon Heavy for this mission — consisting of core B1068, booster B1052, and booster B1053 — was expended due to the need for all available performance. This results from needing to insert the ViaSat-3 Americas satellite directly into geostationary orbit.

The Falcon Heavy, after firing its 27 Merlin engines with a total of 22.82 meganewtons of thrust, launched due east into a trajectory typical for geostationary satellite launches. The second stage flew an extended mission and had a band of gray thermal insulation to keep the stage’s propellant at its proper temperature.

A direct geostationary orbit insertion required the upper stage to perform multiple maneuvers, including the circularization burn at apogee, before releasing the satellite to conduct its mission at an altitude of 35,786 kilometers above Earth. Since the satellite itself does not need to expend fuel on the circularization burn, the fuel saved can extend the spacecraft’s useful life.

Due to the direct geostationary orbit insertion, Falcon Heavy’s boosters were expended by falling into the Atlantic Ocean after separation. The core stage was expended in a similar manner. None of the booster elements contain recovery hardware such as titanium grid fins and landing legs.

Boosters B1052 and B1053 have served as Falcon Heavy boosters on previous flights, while B1052 also served as a Falcon 9 first-stage booster for five launches. B1052 and B1053 flew as side boosters on the Arabsat-6A and STP-2 flights in 2019, making successful dual return to launch site landings at Cape Canaveral Air Force Station.

Falcon Heavy conducts a static test firing of its 27 engines before the ViaSat-3 Americas mission. (Credit: Nathan Barker for NSF)

B1052 was converted to become a Falcon 9 booster before flying the CSG-2, Starlink 4-10, Starlink 4-18, the South Korean Danuri Moon probe, and the Starlink 4-20 missions in 2022. This was B1052’s eighth and last flight and B1053’s third and final launch as well.

After Starlink Group 4-20 last September, B1052 was converted back into a Falcon Heavy side booster for its final flight, while B1053 has not flown since STP-2. B1068 was manufactured strictly as a Falcon Heavy core and is making its first and last flight. Falcon Heavy cores require additional reinforcement and are not used as Falcon 9 boosters.

The main payload for this flight was the ViaSat-3 Americas, the first of three new geostationary communication satellites that together are intended to provide continuous near-global broadband service to 99% of the populated world.

ViaSat-3 satellites, each massing approximately 6,000 kilograms (kg), utilize the Ka-band, and will deploy one of the largest reflectors ever flown.  The reflector, made of carbon fiber, reinforced polymers, and graphite, will be deployed at the end of a boom derived from one that deployed the James Webb Space Telescope’s sunshade.

The ViaSat-3 Americas satellite. (Credit: Viasat)

The ViaSat-3 series will also have eight solar panels that can collectively generate around 25 kilowatts (kW) of power, one of the highest power-generating capabilities ever for any communications satellite. The spacecraft and its solar panels will have a span of 43.9 meters, which is just about a third of the span of the International Space Station.

The power system and reflector will enable the ViaSat-3 Americas to have a throughput of up to one terabit per second, which is double the throughput of Viasat’s entire satellite fleet up to now. The entire ViaSat-3 constellation will have a throughput of up to three terabits per second, up to 500-600% of the capacity of the Viasat network before this year.

ViaSat-3 Americas is planned to use the geostationary orbital slot at 88.9 degrees West and is designed for an orbital lifetime of at least 15 years. The satellite, based on the Boeing 702MP bus, was built at Boeing’s El Segundo, California facility and shipped to Florida aboard a Ukrainian Antonov AN-124 cargo aircraft.

There are two small satellites on this flight were placed into geostationary orbit. The Arcturus satellite, with a mass of 400 kg, was built by Astranis to provide broadband services to the state of Alaska for Pacific Dataport. The spacecraft will use a slot at 163 degrees West longitude.

Arcturus, also known as Aurora 4A, is the first Astranis commercial satellite to be launched. The spacecraft is designed for a lifetime of 10 years. It utilizes the Ku band with a throughput on the order of 7.5 Gbps. The spacecraft, built in San Francisco, will use electric propulsion to maintain its orbit, along with two solar panels to provide electric power.

The Arcturus satellite, the first commercial MicroGEO satellite to fly. (Credit: Astranis)

The Arcturus satellite is one of Astranis’ MicroGEO satellites, which are meant to provide dedicated service to one region. In this case, Arcturus will serve Alaska, whereas other MicroGEO satellites built by the company will serve Peru and mobility markets (air and sea).

The G-Space 1 satellite is a 16U cubesat built in Denmark for Gravity Space. The satellite, massing 22 kg, is designed to support communication services for the internet of things. The satellite contains several payloads. One payload is a bring-into-use placeholder for Indonesia’s PT Pasifik Satelit Nusantara known as the Nusantara H-1A. 

The Nusantara H-1A payload will enable the operator to retain Ka and Ku band rights to a geostationary orbital slot reserved for a satellite that has been delayed. Other payloads on G-Space 1 include an “orbit guard” space situational awareness imaging system and an experimental rendezvous and docking payload. G-Space 1 has a design lifetime of 15 years.

The Falcon Heavy is scheduled to fly three more missions this year. The USSF-52 mission is scheduled for launch no earlier than June 23, while the Echostar 24 (Jupiter 3) payload will fly no earlier than this coming August. The NASA Psyche asteroid probe launch is targeted for Oct. 5.

(Lead image: Falcon Heavy launches – via Julia Bergeron for NSF)

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