The first of two Galileo navigation satellites to be orbited on Arianespace’s May 24 Soyuz flight has been integrated on its payload dispenser system, marking a key step as preparations advance for this medium-lift mission from French Guiana.

Named “Danielė”, the spacecraft was installed last week during activity inside the Spaceport’s S3B payload preparation facility. It is to be joined on the dispenser system by the mission’s other passenger, “Alizée”, whose own installation is forthcoming in a side-by-side arrangement.

The pair are then to be mated atop Soyuz’ Fregat upper stage and encapsulated in the protective payload fairing. Prime contractor OHB System in Bremen, Germany produced the satellites, and their onboard payloads are supplied by UK-based Surrey Satellite Technology Limited (SSTL), which is 99-percent owned by Airbus Defence and Space.

“Danielė” and “Alizée” will become the 13th and 14th FOC (Full Operational Capability) spacecraft to join the Galileo constellation

The May 24 flight is designed Flight VS15 and will be performed from the purpose-built ELS launch complex at Europe’s Spaceport, with Arianespace’s Soyuz carrying out a nearly 3-hour, 48-minute mission to place its Galileo passengers into a targeted circular orbit at an altitude of 23,522 km., inclined 57.394 degrees to the equator. Total payload lift performance is estimated at 1,599 kg.