...has reached a new milestone with integration of the "upper composite"—composed of its ESC-A cryogenic upper stage and the vehicle equipment bay that functions as the launcher's "brains." The activity was performed last week in the Spaceport's Launcher Integration Building at French Guiana, where the upper composite was installed as a single unit atop Ariane 5's core cryogenic stage.

Power for the ESC-A is provided by an HM-7B engine, whose reliability has been proven during years of service on Ariane 5 and with the predecessor Ariane 4 launcher series. Located above the upper stage is Ariane 5's vehicle equipment bay, containing the launcher's onboard computers, inertial guidance units, sequencing electronics, power supplies and telemetry equipment. When the assembled Ariane 5 completes its current check-out phase, it will be ready for transfer to the Spaceport's Final Assembly Building, where it will be equipped with the mission's dual-satellite payload: the Meteosat Second Generation-3 (MSG-3) weather satellite for EUMETSAT (the European Organisation for the Exploitation of Meteorological Satellites); and the EchoStar XVII high-throughput telecommunications platform for Hughes Network Systems.

Ariane 5’s “upper composite” is raised inside the Launcher Integration Building (photo at left) and is moved into position for installation atop the vehicle’s core cryogenic stage (center and right). Photo is courtesy of Arianespace.

Liftoff of this mission is scheduled for June 19. It will follow Arianespace's May 15 launch of another Ariane 5, which currently is in the Spaceport's Final Assembly Building awaiting integration of the mission's JCSAT-13 and VINASAT-2 telecommunications satellites.