UPDATED Aug. 23 3:03 p.m. EDT
PARIS — A six-month joint French-German government study of future launch vehicle and space station investment options has reinforced the German space agency’s preference for an upgraded Ariane 5 rocket instead of a new-generation Ariane 6, and cooperation with the United States on a U.S.-led crew vehicle instead of a European-led alternative, the agency’s chief said Aug. 21.
Johann-Dietrich Woerner, chairman of the German Aerospace Center, DLR, insisted in an interview that he was speaking only for himself, and not for the German government.
The government’s formal position on both subjects will be crafted in the coming weeks as Germany and the 18 other members of the European Space Agency () prepare for a late-November conference to set Europe’s space policy and budget priorities.
As a prelude to this conference, Woerner said, the French and German ministers responsible for space policy will meet Sept. 22 in Zurich along with their counterparts from Italy, Switzerland and Luxembourg. The goal of this meeting is to iron out remaining differences, particularly between France and Germany — which together account for about 50 percent of ESA’s annual member-state contributions — in advance of the November meeting in Caserta, Italy.
In an attempt to head off a confrontation at the conference between Europe’s two biggest space powers, the French and German governments in February appointed a committee to investigate the two most controversial items likely to be raised at the meeting.
The French-German committee, including representatives from DLR and the French space agency, CNES, submitted its report to the two government ministries in late July. The report has not been made public.
The first of the two contentious issues assessed in the report is whether to complete development of the Ariane 5 Midlife Evolution (ME) rocket, giving the vehicle a 20 percent boost in payload-carrying power and a reignitable upper stage.
Opposing that idea was a French view that Europe should bypass Ariane 5 ME and begin immediate investment in a next-generation rocket with a modular design. Unlike its more powerful predecessor, built to carry two satellites at a time to geostationary transfer orbit, the new vehicle would be designed to profitably carry single satellites weighing 2,500 to 6,500 kilograms, with a possible increase to 8,000 kilograms.
Backers of the new rocket, tentatively called Ariane 6, say the commercial market is developing in such a way as to make the current Ariane 5 too costly to remain competitive in the coming years. Without a dominant share of the commercial market, these officials say, Europe’sconsortium cannot make ends meet and will be even more dependent than it is today on annual government support payments.
Evry, France-based Arianespace, which operates the Ariane 5, needs about 120 million euros ($150 million) in annual government payments to break even, despite the fact that the rocket has captured about 50 percent of the competitive global market and has posted 50 consecutive launch successes.
Ariane 5 ME backers say debt-laden ESA governments cannot afford to begin full-scale development of the Ariane 6 now, and should finish the work on Ariane 5 ME that started in 2008, when ESA members agreed to spend 357 million euros on the effort, mainly on the Vinci restartable engine.
ESA now assumes it will cost about 1.4 billion euros to complete Ariane 5 ME, including an inaugural flight by 2018.
To sweeten the appeal of Ariane 5 ME, Ariane 5 contractor Astrium Space Transportation in early August wrote ESA to guarantee that, under certain conditions, the upgraded rocket will enable Arianespace to operate with no annual support payments once it is operational in 2018.
The conditions, according to Woerner, include industrial work-share concessions that will give Astrium Space Transportation a de facto monopoly, a scenario he said may be acceptable after further discussion.
“If we are going to accept these conditions, we have to be sure that the guarantee is very, very clear,” Woerner said.
Woerner said that while different cost estimates have been assigned to the Ariane 6 option, the price tag is likely to be around 4.5 billion euros over 10 years. During that time, he said, the current version of Ariane 5 will require 120 million euros per year in support payments, which brings the total cost to ESA governments to 5.7 billion euros over 10 years.
Woerner said pursuing Ariane 5 ME and Ariane 6 development simultaneously might be no more expensive than proceeding directly to Ariane 6 because of synergies in the two vehicles’ designs that would shave total costs by 15-20 percent or so.
But the Ariane 5 ME option is still the most cost-effective alternative now and leaves ESA governments with sufficient additional financing to back other ESA programs in Earth observation and relating to the space station.
The French-German study also examined whether Europe should join the United States in developing the Orion deep-space crew transport vehicle by investing the 450 million euros Europe owes NASA for space station charges to 2020.
A French alternative, which had found support in Italy, proposed a Europe-led vehicle that would operate in low Earth orbit and perform a variety of missions, including possible removal of orbital debris.
Woerner said the alternative vehicle would cost far more than the 450 million euros ESA has to spend to repay NASA for station use, and that Europe’s current financial condition will render that option unfeasible for now.
Whether France will be willing to invest in the Orion vehicle remains unclear. A CNES official said Aug. 22 that the agency will reserve comment about the report until the French government has reviewed it.