Arianespace has delivered another Ariane 5 to the launch zone at Europe's Spaceport in French Guiana, clearing the way for tomorrow's heavy-lift mission with a pair of telecommunications satellites: Sky Muster II and GSAT-18.

Riding atop a mobile launch table, the Ariane 5 vehicle has completed its transfer from the Spaceport's Final Assembly Building – where payload integration occurred – to the dedicated ELA-3 launch complex. With this rollout completed, the final countdown will begin for an October 4 liftoff at the start of a 1-hr., 15-min. launch window opening at 5:30 p.m. local time in French Guiana.

Tomorrow's mission is designated Flight VA231, and it has an estimated payload performance of 10,660 kg. – a total that factors in Sky Muster II and GSAT-18, plus the dual-satellite dispenser system and integration hardware. Both passengers are to be deployed to geostationary transfer orbit during a 32-min. flight sequence.

Arianespace supports Australian and Indian customers

Sky Muster II is the mission's upper passenger and will be released first in the flight sequence at 28 min. after liftoff. Produced by SSL (Space Systems Loral) for operator nbn, it will help extend high-speed internet across Australia, including the country's rural and isolated regions.

To be deployed from Ariane 5's lower passenger position is GSAT-18, which was built by the Indian Space Research Organisation (ISRO) to strengthen its current fleet of 14 operational telecommunications satellites. This spacecraft's separation will occur approximately 32 min. after liftoff – completing the October 4 mission.

As the fifth heavy-lift Ariane 5 flight so far in 2016, tomorrow's launch will continue a busy year of mission activity for Arianespace's full family of launchers, which also has included two flights performed with the medium-lift Soyuz and one using the lightweight Vega.