Europe's two new launchers to fly from the French Guiana spaceport next year are facing cost challenges to their successful commercial introduction.

Samara Space Center Soyuz 2-1a and its more powerful 2-1b variant, purchased for launch from French Guiana, have a price tag almost double that when bought for Baikonur cosmodrome launches.

In addition plans for the Vega booster to have a more cost-effective engine that replaces its upper stages have been postponed because overall launcher costs could not be reduced.

"When [Russia] sells us Soyuz [for French Guiana] the launcher itself increases in cost, almost doubling. This shows us that the price is not linked to cost but very much linked to politics," explains Italian space agency commissioner Enrico Saggese.

He admits that the long-distance logistics of operating Soyuz in South America is a factor, but the dramatic overall price hike, in his view, had to be political.

Because of growing competition from developing countries, Vega's consortium of seven ESA member states had wanted to replace the Attitude Vernier Upper Module (AVUM) to improve the booster's performance and cost-effectiveness.

Today Vega consists of three solid motor stages and its AVUM fourth stage that uses storable propellant. The use of EADS Astrium's Aestus II engine has also been studied. Aestus powers the Ariane 5 upper stage. But Saggese says that the partners found that "when computed, the cost [of Vega with Aestus II] was increasing without advantage in mass capability".

Instead, after Vega's maiden flight Germany and the Vega team will work on a new propulsion system, which could replace the third and fourth stages of Vega with a single stage that reduces the overall costs of the launch vehicle. Germany has been interested in joining the Vega programme, which includes Italy, Spain, Sweden and Switzerland.

Source: Flight Daily News