A Closer Look at Ariane 6

Two possible configurations for the Ariane 6 launch vehicle with two and three strap-on boosters at the base. (Credits: ESA /CNES/Arianespace)

CNES has published an overview of the planned Ariane 6 launch vehicle, which could eventually replace Ariane 5 in 2021 if the project gains the support of ESA members next year.

Ariane 6 would be a three-stage rocket capable of launching communications satellites weighing up to 6.5 metric tons into geosynchronous transfer orbit orbit (GTO). It is designed to launch single communications satellites rather than the pairs of them that the larger Ariane 5 launches.

Ariane 6 would have two solid or powder stages and an upper stage that uses hydrogen and liquid oxygen. (Credit: ESA / CNES / Arianespace)

Ariane 6’s first two stages would use P135 engines powered by solid or powder propellant. The third stage would use a new Vinci motor fueled by hydrogen and liquid oxygen. The rocket would have two or three strap-on solid-rocket motors on its first stage depending upon payload requirements.

The impetus behind the Ariane 6 is the larger growth of communications satellites. Not only are they getting heavier, it is increasingly difficult to find pairs of them to launch on the Ariane 5, which has a capacity of 9.4 metric tons to GTO.

Further, the launch market is very competitive, with Russia’s Proton and Ukraine’s Zenit boosters in the mix. By 2020, the Chinese Long March rockets — which account for very little of the commercial market — could also be a force, according to CNES.

Interestingly, the French space agency makes no mention of SpaceX and the Falcon 9 and Falcon Heavy launch vehicles. The Falcon 9 is already a force in the market, having captured many launch contracts before it has even placed a single communications satellite into orbit. That is a sign that the satellite community really wants competitors to the existing fleet of commercial boosters.

Europe has been divided over how to meet this new threat. The French have favored immediately beginning work on Ariane 6. The Germans — who have replaced France as ESA’s largest national contributor — have favored an interim plan to upgrade Ariane 5 booster.

The Ariane 5 ME (Mid-life Evolution), set to launch in 2016 or 2017, would enable the rocket to lift 11.2 metric tons to GTO.  The Ariane 5 ME could also cut launch current launch costs by up to 20 percent, reducing the need for European governments to subsidize the vehicle. The upgraded launcher also would feature the new Vinci cryogenic upper stage, which is also slated for use on Ariane 6.

When SpaceX CEO Elon Musk was asked last year what Europe should do, he said they should start on Ariane 6 immediately. Even with the upgrades, Ariane 5 had no chance to compete with Falcon 9, he said.

“Does this mean Elon Musk wants to contribute to Ariane 6? I don’t know,” ESA Director General Jean-Jacques Dordain joked. “I must say we are more than ready to have additional contributors.”

It was a funny riposte, but an ironic one: Dordain actually agreed with Musk. He personally backed the French plan to immediately go forward with the development of Ariane 6.

ESA didn’t follow his advice. At the space agency’s ministerial meeting in November, officials instead backed immediate expenditures on Ariane 5 ME while going forward with  detailed definition studies on Ariane 6. They postponed any decision on whether to fully fund the new Ariane 6 booster until they meet again in 2014.