The no. 1 Soyuz launcher at the Spaceport in French Guiana has completed the first step of its initial build-up, with all four of the vehicle's first stage strap-on boosters now mated to the Block A core second stage. This activity is taking place in the Launcher Integration Building at the Spaceport's new Soyuz operating base, which is being readied for the Russian-built medium-lift vehicle's service introduction later this year.

The launcher's current build-up is part of regular maintenance checks that are typical for Soyuz vehicles in storage awaiting liftoff, and the integration also is being used to qualify assembly processes in the Spaceport's new Launcher Integration Building. These procedures are similar to those used for decades in Soyuz operations from the Baikonur Cosmodrome in Kazakhstan and the Plesetsk Cosmodrome in Russia, with more than 1,750 flights performed to date from those facilities. With completion of the boosters' mating to the no. 1 Soyuz' Block A stage on Saturday, May 8 at the Spaceport, pneumatic testing of this integrated portion of the launcher is now underway. The next step will be installation of the Soyuz' Block I third stage, enabling electrical testing to be performed with the launcher's three assembled stages. The launcher being built-up is one of two Soyuz 2-1a vehicles delivered to the Spaceport last November, and its is scheduled to be used on the maiden flight from French Guiana — carrying the HYLAS 1 telecommunications satellite for Avanti Communications.