Arianespace's new Spaceport processing facility has fueled another Fregat stage. This upper stage for the medium-lift Soyuz launcher will be used for the May 24 flight from French Guiana with two European Galileo navigation satellites.

Named the FCube (Fregat Fueling Facility), the purpose-built installation is utilized to "top off" Fregat upper stages during Soyuz launch campaigns at the Spaceport. In service since last year, the FCube supports Arianespace's sustained launch pace - giving the company greater flexibility in managing its mission manifest, while also increasing launch capacity with Soyuz and its other launch vehicle family members: the heavy-lift Ariane 5 and lightweight Vega.

Fregat upper stages are produced by NPO Lavochkin, a company that is part of the Soyuz launcher's Russian industrial team. Fregat serves as an autonomous upper stage enabling Soyuz to perform a full range of missions. During its processing in the FCube facility, Fregat was fueled with UDMH (unsymmetrical dimethyl hydrazine) and NTO (nitrogen tetroxide) storable propellants that are loaded into spherical tanks.

After its fueling in the FCube, the Fregat for Arianespace's Flight VS15 was transferred by road to the Spaceport's S3B clean room. At this facility, the upper stage will be integrated with passengers for this month's Soyuz mission: the latest two Galileo Full Operational Capability (FOC) spacecraft for Europe's satellite-based navigation system. This will create the "upper composite," which is protected by a payload fairing during the initial phase of flight through the atmosphere.

For Arianespace's May 24 mission, Fregat will perform a first burn, followed by a 3-plus hour ballistic phase. The Fregat will ignite its engine again to reach the circular orbit for separation of the two Galileo spacecraft - which will enter Orbital Plane A of the navigation satellite constellation.

Galileo's FOC phase is funded and managed by the European Commission, which has designated the European Space Agency as the system's design and procurement agent. OHB System in Bremen, Germany, is prime contractor, producing the Galileo FOC satellites. The satellites' navigation system is supplied by UK-based Surrey Satellite Technology Ltd (SSTL), which is 99% owned by Airbus Defence and Space.

Flight VS15 is one of up to 12 Arianespace missions targeted for 2016 with the company's complete launcher family. So far this year, Arianespace has performed three launches: two with Ariane 5, and one utilizing Soyuz.