The first launches by the veteran Russian rocket Soyuz and a new light rocket called Vega from Europe's space base will be postponed to 2010, the European Space Agency (ESA) said on Monday.
They had been scheduled to take place by the end of the year.
A workhorse of space, Soyuz is being added to ESA's launch pad at Kourou, French Guiana, to provide the agency with operational flexibility, to cope with medium-level payloads while the Ariane 5 rocket takes care of heavy payloads.
ESA Director General Jean-Jacques Dordain told reporters at the Paris Air Show that there were delays in a Russian-made mobile gantry that will be added to the launch pad.
"The mobile gantry should have been integrated now, meaning that the first launch of Soyuz from French Guiana will take place now in the first weeks of 2010 instead of the end of 2009," Dordain said.
Soyuz until now has only been launched from Plesetsk, northern Russia, and from Baikonur, in Kazakhstan, and has not used a gantry for support.
The version that will be used in Kourou will be a "Soyuz 2", able to hoist three tonnes into geostationary orbit, compared to 1.7 tonnes that can be launched from Baikonur.
Meanwhile, Dordain added there were delays in completing the testing of a new light rocket called Vega that will be the third component of the flexible launcher strategy.
Vega, with a payload capacity of 1.5 tonnes, is to be deployed from the launchpad of the old Ariane-1 rocket. ESA had hoped to have the rocket take its maiden flight by the end of 2009.
"Unfortunately we had some delays in the integratedness and the qualification of some sub-systems of the launcher, which mean that we have postponed the start of the last phase of the (test) programme... from May to December 09, meaning that there will be a delay of several months in the first flight of Vega," said Dordain.
"We shall fix the date of this first flight by the end of the year," after a combined test of the rocket and ground facilities, he said.
The three rocket systems are being marketed by the Arianespace launch company.
(c) 2009 AFP
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