Eurostar (satellite bus)

The original Eurostar E1000 satellite was designed for the Inmarsat-2 fleet requirements by an international team led by Matra Marconi Space and British Aerospace Space Systems (BAe Dynamics), the former of which would ultimately acquire BAe Dynamics to eventually become Astrium and eventually merge with Airbus Military to form the present Airbus Defence and Space. Three-axis stabilized, and designed for a 10-year service life, the Inmarsat-2 had 4 (+2) L-band transponders and 1 (+1) C-Band transponders. The satellite featured a launch mass of 1.31 t (2,900 lb), however, the satellite bus was designed to weigh up to 2.5 t (5,500 lb) to accommodate future customer requirements. Subsequently, the spacecraft also came with different payload power options ranging from 1300 W to 3000 W. This degree of customization was the result of a highly modular design that would carry over onto the upgraded variants.[3][4]

A total of four satellites based on the E1000 bus have been built and launched, all of which were for Inmarsat.

The Eurostar E2000, which debuted with France Telecom as the launch customer in December of 1991, was a larger and more capable upgrade of the E1000. It was developed from a set of requirements by the French Space Agency (CNES) and the French Ministry of Armed Forces via the Directorate-General for Armaments (DGA). The DGA had decided to repartner with CNES in order to add X-Band capabilities to the mission to enable the creation of their Syracuse II military ground-based telecommunications network, and to replace and enhance the role of the Syracuse I systems aboard the aging Telecom-1 fleet. The first of the satellites to be launched would be the Telecom 2A. Each of the four Telecom-2 satellites in the constellation had 10 x C-Band transponders, 14 x Ku-Band transponders and 5 x X-Band transponders. Despite the increase in capabilities, the E2000 bus used for Telecom-2 was only slightly heavier than the E1000, with an on-orbit mass of 1.38 t (3,000 lb) and a dry weight of 700 kilograms (1,500 lb), however, like its predecessor, was also designed to accommodate larger payloads with a total launch mass of up to 2.5 t (5,500 lb), should the customer require it. The E2000’s operational/maneuverability life varied by customer, but ranged from 7 to 10 years. The E2000’s main power comes from two swivelling solar arrays, with later models capable of producing up to 3600W per array, or 6200 W total with an optional array spanning 22 m (72 ft).[5][4]

The E2000+ satellite bus offered a series of significant upgrades, in addition to being slightly larger than the E2000. Upgrades included:[4]

• Increased efficiency in its ability to operate over 40 transponders
• Increased maximum launch mass of up to 3.4 t (7,500 lb)
• Increased payload power up to 6.2 kW (6,200 W)
• Capability to carry up to 48 high powered amplifiers in addition to large multiple antenna configurations
• Increased maneuverability life to 15 years
• Integration of CCSDS telemetry and telecommand protocols.

The first E2000+ customer was Eutelsat’s Hot Bird 2. At least 23 E2000 and E2000+ satellite busses were built, with a total of 22 launches.

The Eurostar E3000 satellite bus was first launched in 2004 with Eutesat’s Eutelsat W3A payload. Building upon the idea of modularity, the satellite itself can be built with several modules to serve different missions, all based around a common service module, communications module with 1,2, or 3 floors, a chemical or chemical-electric propulsion module, and scalable payload power options. Satellite power can be up to 16 kW (16,000 W) stored in either NiH2 or Lithium-Ion batteries. The solar array’s wingspan is also scalable, and capable of deploying to be up to 45 m (148 ft) wide. The spacecraft’s maximum launch mass has increased to 6.4 t (14,000 lb), while its telecommunications payload capacity has been increased to up to 120 installed high-power amplifiers/transponders. In 2018, Airbus D&S launched the first E3000e - a modified E3000 with all-electric propulsion, removing the standard propulsion module and over 2,000 kg (4,400 lb) of excess mass with it. SES-12 for SES S.A. was the first customer for the E3000e in June of 2018. At least 48 x E3000 and E3000e satellite busses had been built and launched by the end of 2018.

An improved model based on the E3000e called the Eurostar Neo was announced in 2017, and offers electric, hybrid, or chemical propulsion, in addition to a scalable power range of 7 kW to 25 kW. As of 2020, a total of 84 Eurostar satellites had been ordered, with 6 E3000e satellites already in operation.[6]