European Freighter Heads To Space Station

PARIS — European space officials are hoping that the flawless launch of Europe’s second Automated Transfer Vehicle (ATV-2) to the International Space Station (ISS) Feb. 16 will buoy efforts to fund a planned extension of the facility.

The cargo vessel, christened Johannes Kepler, lifted off from the European spaceport in Kourou, French Guiana, at 6:50 p.m. local time atop an Ariane 5 ES rocket, setting up a scheduled docking with the ISS on Feb. 24.

Soon after the launch, which had to be postponed 24 hr. because of a main stage liquid oxygen tank level measurement anomaly, the vehicle deployed its four solar arrays and prepared for early orbit operations in the same orbital plane as the ISS — but well below its 350-km (220-mi.) orbit — before beginning its final ascent.

The mission, which inaugurates regular ATV service to the station, had initially been scheduled for December but had to be pushed back because of ISS and Ariane 5 scheduling issues. It will deliver cargo, propellant and oxygen to the orbital outpost but — unlike the first ATV, Jules Verne — no water. A series of design improvements to the ATV and the Ariane 5 ES solid boosters subsequent to the Jules Verne launch in March 2008, including lighter racks designed for soft packaging, allowed cargo capacity to be increased by 300 kg (660 lb.) and 2 cubic meters.

Design changes

Other design changes served to correct defects detected during the inaugural mission, including a pressure regulator latch valve failure and degradation of multilayered insulation mounted on the vessel exterior. Others reflected development improvements to items, such as the solar array drive mechanism, that could not be completed by the first flight, to add redundancy or to continue structural dynamic modeling.

The vessel will remain docked to the ISS for three months and perform several station reboosts during the period before undocking and return for a destructive re-entry into the atmosphere.

ATV-2 will dock directly and autonomously with the Russian Zvezda module, in a short, eight-day campaign, instead of performing practice demonstrations that caused the Jules Verne rendezvous and docking campaign to stretch for a full month. The shorter timeline also reflects the tight manifest for ISS access, with the H-II Transfer Vehicle (HTV) — the second of which is currently docked to Node-2 — Progress and the space shuttle all competing for docking space with the ATV. Engineers had initially envisioned an 11-day campaign.

ISS logistics

Together, the ATV, HTV and Progress will be responsible for ensuring a secure logistics lifeline to the ISS after the shuttle is phased out this year and until commercial supply vehicles enter service later in the decade. Four other ATVs are currently planned. ATV-3, known as Edoardo Amaldi, is due to be ready for shipment to Kourou by August, for launch in about 12 months, says Simona di Pippo, manned spaceflight director for the European Space Agency (ESA). The vessel will include a package of improvements now in development. Assembly of ATV-4 and production of initial structures for 5, to follow by 2014, are under way.

Agency and industry executives hope the successful launch will encourage ESA member states to agree to support the planned ISS life extension with generous funding. Germany, Europe’s biggest station backer, estimates at least €380 million ($515 million) per year will be needed for the station over the next decade, including money to purchase an additional two ATVs to cover provision of another five years of NASA services, and to bankroll ATV design enhancements. Astrium says it has already submitted a proposal for additional ATVs.