PONTE VEDRA, Florida — A Europeanized Russian Soyuz rocket on Aug. 22 successfully placed two European Galileo positioning, navigation and timing satellites into medium Earth orbit in the first launch of Galileo’s fully operational satellite models.
European Space Agency officials said they expect to launch another pair of Galileo satellites aboard a Europeanized Soyuz in December, with 18 more identical satellites to launch between 2015 and 2017.
Operating from Europe’s Guiana Space Center in French Guiana, on the northeast coast of South America, the four-stage Soyuz rocket, including its Fregat upper stage, placed the two 732.8-kilogram Galileo satellites into a medium Earth orbit inclined at 56 degrees relative to the equator. Their operating altitude is 23,222 kilometers.
Ground teams confirmed that the two satellites were healthy in orbit and sending signals.
They join four In-Orbit Validation Galileo spacecraft launched in 2011 and 2012. The full constellation is expected to be 30 satellites in orbit, including three spares. All the satellites are designed to operate for at least 12 years.
OHB AG of Bremen, Germany, is prime contractor for the 22 Full Operational Capability (FOC) satellites ordered so far byand Galileo’s owner, the 28-nation European Union. OHB and its team, including payload provider Surrey Satellite Technology Ltd. of Britain, are about a year late in delivering the spacecraft.
ESA officials said the next two satellites have completed their key test cycles in a thermal vacuum chamber. Didier Faivre, ESA’s director of navigation, said the agency has secured from launch service providera launch date in December for the next two.
After a long debate at the European Commission about whether to rely exclusively on the medium-lift Soyuz or also include Europe’s heavy-lift Ariane 5 rocket in the Galileo program, the commission has agreed to a mix of the two vehicles.
Faivre and Arianespace Chief Executive Stephane Israel on Aug. 21 signed a contract, valued at slightly more than 500 million euros ($681 million), for three Ariane 5 rockets, each to launch four Galileo satellites between 2015 and 2017.
Ariane 5 prime contractor Airbus Defence and Space has designed a special dispenser to house the four Galileo spacecraft and to release them in orbit from the Ariane 5.
The Galileo program is fully funded by the European Commission, which is the European Union’s executive arm, through 2020. But the year’s delay, plus the additional costs of the Ariane 5 dispenser — co-funded by ESA and the European Commission — and the need to build at least four more satellites to complete the 30-satellite constellation has nonetheless put pressure on the budget.
In the past, the European Commission has threatened to slap financial penalties on the OHB-led team to compensate for delay-related cost overruns. Whether that will occur remains unclear.
Faivre said the mix of Soyuz and Ariane 5 rockets should be able to assure that six to eight satellites are launched in 2015, with an additional six to eight in 2016. The last of the OHB-built satellites should be in orbit in 2017, Faivre said in an Aug. 20 briefing with journalists.
The OHB satellites are slightly heavier than the four validation spacecraft, and are designed to deliver 1.9 kilowatts of power compared to the earlier satellites’ 1.4 kilowatts. One of the reasons for the sharp increase in power was to enable Galileo’s jam-resistant Public Regulated Service signal, reserved for government use, to function even if its frequencies partially overlay spectrum used by China’s Beidou navigation constellation.
A signal overlay has no effect on either system’s performance, but would become problematic in the event of a conflict in which either China or Europe would seek to jam the other’s signals. In that event, jammers would interfere with both services.
With the technical hurdles of the new satellite design now apparently resolved, ESA will focus its attention on managing the regular delivery and launch of spacecraft — a serial production that the agency has never before managed.
“We need to demonstrate regular production cadence for the satellites and we’ve never done this before,” Faivre said. As a research and development organization, ESA is unaccustomed to building multiple models of identical satellites.
Faivre said the Galileo satellites, having received their payloads from Britain, move from integration at OHB in Germany to ESA’s European Space Research and Technology Centre in Noordwijk, Netherlands. From there they are flown to the French Guiana spaceport for final tests and integration into the Soyuz and Ariane 5 rockets.
Evry, France-based Arianespace, which manages launches of Europe’s light-class Vega rocket in addition to the Ariane 5 and Soyuz campaigns, has a full schedule for 2015 and has already been forced to arbitrate between ESA and commercial customers that want priority use of Soyuz.
The order of the final four first-generation Galileo satellites is not imminent. Faivre said ESA wants first to verify the system performance of the current spacecraft to be able to make modifications where necessary.
Also to be decided is whether to ask the OHB team to continue the current production for an additional four spacecraft, or to select another contractor — Airbus andboth want the order — to start a new production line.
European Commission and ESA officials have said OHB likely would best Airbus and Thales Alenia Space for a four-satellite order given that the nonrecurring engineering charges have been incurred during construction of the 22 satellites.
But these same government officials have also said they would prefer not to be left with a monopoly Galileo supplier as they look to a second-generation system.