Launch date
October 23, 2021
SES, French DGA
Prime contractor(s)
Thales Alenia Space
Launch vehicle
Ariane 5
Launch site
Spaceport, French Guiana (Guiana Space Center)
Geostationary transfer orbit (GTO)


Arianespace’s eleventh launch of 2021 with the second Ariane 5 of the year will place its satellite passengers into geostationary transfer orbit. The launcher will be carrying a total payload of approximately 11,210 kg.

The launch will be performed in Kourou, French Guiana.

Between 09:01 p.m. and 11:30 p.m.
Washington, D.C.
Between 10:01 p.m. and 00:30 a.m.
Kourou, French Guiana
Between 10:01 p.m. and 00:30 a.m.
Universal time (UTC)
Between 03:01 a.m. and 05:30 a.m.
Paris, France
Between 10:01 a.m. and 12:30 p.m.
Tokyo, Japan


SES-17 satellite

This High Throughput telecommunication satellite provides excellent coverage over the Americas, the Caribbean and the Atlantic Ocean and has been designed to transform the aviation connectivity landscape, address data demands across maritime, government and enterprise segments, as well as to accelerate digital inclusion initiatives. It features almost 200 spot beams, the power of which can be dynamically adjusted in step with customers’ changing requirements. It is also the first SES satellite to have a totally digital payload, powered by an advanced digital transparent processor (DTP), enabling far greater flexibility and efficiency than previously available. The satellite will form a multi-orbit network adaptable to varying bandwidth and latency requirements, operating with SES’s next generation non-geosynchronous satellite system, O3b mPOWER.

The Thales Alenia Space’s 5th generation Digital Transparent Processor (DTP) embarked on SES-17 allows for easy frequency conversions as well as unlimited gateway switching and traffic routing. Combined to flexible amplifiers, it will meet customer’s changing requirements and real time traffic demands.

  • Since 1984, SES has entrusted 42 satellites to Arianespace, demonstrating the trust of this strong relationship.
  • SES-17 will be the 164th Thales Alenia Space satellite to be launched by Arianespace; there are currently four Thales Alenia Space satellites in Arianespace’s backlog, including SES-17.

This military communications satellite, commissioned by the Armament General Directorate DGA, will allow to connect the armed forces together when deployed. At sea, in the air or on the ground, militaries need secured and powerful communication means in order to be able to exchange information with the command center. Thanks to its state-of-the-art equipment (anti-jamming antenna and digital transparent processor on board), SYRACUSE 4A will guarantee a high resistance to extreme jamming methods. At the service of France’s sovereignty, the satellite will also support NATO and European-led operations.

Developed under the leadership of the DGA in close coordination with the national center for space studies (CNES), the Space Command of the French Air and Space Force and the other armed forces, SYRACUSE 4A was built by Thales Alenia Space. In the upcoming years, two other military telecommunications satellites will join it in order to create a constellation that will serve the needs of the Armed forces in an ever-growing digitalization of the battlefield. SYRACUSE 4A will connect most naval vessels, moving armored vehicles or aircraft: in particular Griffon armored vehicles, upcoming Suffren attack submarines or the tanker Phoenix.

In order to complete this new generation of satellites, the DGA also contracted Thales to renew the ground segment with the construction of 200 new stations in order to provide state of the art capabilities to the French Armed Forces.

  • SYRACUSE 4A will be the 165th Thales Alenia Space satellite to be launched by Arianespace.
  • This satellite will be the 46th one that Arianespace launches for French Institutions.
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