China has moved a step closer to completing its own navigation and positioning satellite network with the launch of two more navigation satellites.
It brings the Beidou system, which became operational with coverage of China last December, to 13 satellites.
To have global coverage, the country eventually aims to have 35 satellites in orbit by 2020.
China hopes that Beidou will wean it off the US Global Positioning System.
That means the system is now partially operational, and competes with the functioning US and Russian systems. 24 out of 31 of Russia's Glonass satellites are operational. Meanwhile Europe has 2 out of 26 of its Galileo GPS satellites in position.
Full story here http://www.bbc.com/news/technology-17896353


I heard a rumour that during the Gulf wars, those without  military GPS were restricted accuracy in sensitive areas!