First Ariane 5 flight of 2018 to deliver SES-14 and Al Yah 3 communications satellites into orbit
On Thursday, January 25, Europe’s flagship Ariane 5 booster is scheduled to fly for the first time this year. The rocket is being prepared to orbit the SES-14 and Al Yah 3 communications satellites.
Ariane 5 is slated to take to the skies from Ariane Launch Complex No. 3 (ELA 3) located in Kourou, French Guiana. The 45-minute launch window opens at 22:20 GMT (5:20 p.m. EST).
Preparations for the mission, designated VA241 in Arianespace’s numbering system, commenced with the arrival the Al Yah 3 satellite in late November of 2017. The spacecraft was fueled in mid-December and was then readied for its remaining pre-launch preparations.
SES-14 was shipped to the spaceport in French Guiana on Dec. 22, 2017 and its fueling operations were carried out from January 3 until January 5, 2018. Afterward, on Jan. 10, the satellite was integrated on the launch vehicle’s payload adapter. The same was procedure done with the Al Yah satellite 3 two days later.
By January 16, both satellites were encapsulated in the protective payload fairing and were ready for pre-launch payload checks.
The launch rehearsal was conducted on January 19 and four days later, the launch vehicle itselfas well as its payload passed the launch readiness review, what means that they are flight-ready. The rollout of the rocket from the Final Assembly Building (BAF) to the launch pad is scheduled to take place on Wednesday, January 24.
Thursday’s flight is expected to last for approximately 35 minutes, ending with the separation of Al Yah 3. If everything goes as it is currently planned, SES-14 will have been deployed eight minutes earlier. Both satellites are planned to be injected into geostationary transfer orbits (GTO).
Manufactured by Airbus Defence and Space, the SES-14 telecommunications satellite weighs approximately 4.4 metric tons and has dimensions of 23 x 17.7 x 8.86 feet (7 x 5.4 x 2.7 meters). It is based on the E3000 EOR platform with an onboard power of 16 kW and is fitted with two deployable solar arrays.
When it reaches orbit, SES-14 will be operated by the Luxembourg-based telecommunications satellite operator SES for a designed lifetime of some 15 years. Positioned 47.5 degrees West, the spacecraft is being sent aloft so as to offer its services to Latin America, the Caribbean, North America and the North Atlantic region with its C- and Ku-band wide beam coverage, as well as Ku-band high-throughput spot beams coverage.
SES-14 also carries the Global-Scale Observations of the Limb and Disk (GOLD), as a hosted payload for NASA.
GOLD’s main goal is to advance humanity’s understanding of the space environment. The payload is designed to examine the response of the upper atmosphere to forces from the Sun, the magnetosphere, and the lower atmosphere.
Al Yah 3 was built by Dulles, Virginia-based Orbital ATK for the United Arab Emirate’s (UAE) Al Yah Satellite Communications Company (Yahsat). The satellite has a mass of nearly 3.8 metric tons and its dimensions are 17 x 11 x 9.4 feet (5.18 x 3.35 x 2.87 meters). The spacecraft is based on the GEOStar-3 bus and has two deployable solar arrays and an onboard power of 8.0 kW. It is designed to be operational for 15 years.
Al Yah 3 is equipped to transmit in 53 active Ka-band user beams and four gateway beams. It should be positioned 20 degrees West from where it will provide its services to Brazil and Africa.
If everything works, the satellite will offer two-way communications services to facilitate high-speed delivery of data to end-user applications such as broadband Internet and corporate networking as well as IP backhaul for telecommunications service providers.
The Ariane 5 in its ECA configuration, which will be employed for Thursday’s launch, is the heavy-lift rocket Arianespace uses for missions to geostationary transfer orbit (GTO) and usually carries two telecommunications satellite payloads.
The flight is powered during the initial flight phase by a cryogenic core stage and two solid rocket boosters, followed by the use of a cryogenic upper stage for orbital injection of the payload.
The 180-foot (54.8-meter) tall ECA is an improved version of the Ariane 5 launcher and is designed to deliver payloads, primarily communications satellites, which weigh up to 10 metric tons.
Although it has the same general architecture, some significant changes were made to the basic structure of the generic version of this launch vehicle to increase thrust and enable it to carry heavier payloads. The ECA is also used by institutional customers for non-GTO missions; for example, launching the European Space Agency’s Herschel and Planck scientific missions in 2008.
As was noted in an earlier article appearing on SpaceFlight Insider, After more than twenty years in service, the Ariane 5 launch vehicle is going to be taken out of service. The European rocket was first flown in June of 1996, and ArianeSpace has now ordered the final ten Ariane 5 rockets. The booster is scheduled to be replaced by the new Ariane 6 launcher.
The Ariane 5 itself, succeeded the Ariane 4 launch vehicle, but was not derived from this earlier system. The rocket’s cryogenic main stage burns hydrogen and oxygen, using the Vulcain 2 engine that is capable of producing some 310,000 pounds of thrust.
Tomasz Nowakowski is the owner of Astro Watch, one of the premier astronomy and science-related blogs on the internet. Nowakowski reached out to SpaceFlight Insider in an effort to have the two space-related websites collaborate. Nowakowski's generous offer was gratefully received with the two organizations now working to better relay important developments as they pertain to space exploration.