Europe will launch an extra pair of satellites this year in a bid to speed up full deployment of its multi-billion-euro Galileo sat-nav system, launch firm Arianespace said Thursday.
The additional launch from Europe's spaceport in Kourou, French Guiana, is planned for May 2016, followed by a already scheduled four-satellite launch towards the end of the year, the company said in a statement.
"With these two launches, six new galileo satellites will be deployed in 2016, as in 2015, bringing the total number in the constellation to 18 by the end of the year," said Arianespace.
Galileo, Europe's rival to America's GPS, will ultimately comprise 30 orbiters. Arianespace has earlier said that initial services can start once 16 are in place.
The project, which will also provide crucial search-and-rescue services, has been plagued by delays, technical glitches and budgetary difficulties.
The launch of the seventh and eighth orbiters in March last year was about three months late to allow engineers time to probe an August 2014 mishap that sent satellites five and six into a lopsided orbit.
The pair have since been manoeuvred into a better, more circular path.
The mishap was blamed on frozen fuel pipes on the Soyuz rocket's fourth stage, called Fregat—a problem the European Space Agency says has since been fixed.
The launch of satellites five and six—meant to have been the first fully operational Galileo orbiters—had itself been delayed by more than a year due to "technical difficulties".
The first four orbiters were launched in 2011 and 2012.
The European Commission has budgeted seven billion euros ($7.7 billion) for the project until 2020.
The remaining satellites will be launched using a combination of Russian Soyuz rockets, which can take two into space at a time, and Europe's own Ariane 5 ES launcher, which is being adapted to handle four.
The extra Soyuz launch for 2016 had been approved by the European Commission, the European Union's executive body and programme manager of the Galileo programme, said the statement.
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