PARIS — Mobile satellite services provider Inmarsat on Oct. 7 said it had exercised an option with satellite builder Boeing Space and Intelligence Systems for a fourth Ka-band Global Xpress satellite to serve as a spare in case one of the three others under construction is lost in a launch failure.
London-based Inmarsat said the fourth satellite, to cost between $220 million and $250 million, will be used to expand the company’s mobile broadband coverage in the event it is not required to replace a lost satellite.
Three satellites in geostationary orbit can effectively cover the world, except the poles. The three Global Xpress satellites El Segundo, Calif.-based Boeing is building already are expected to be launched starting late this year, with full commercial service to start in late 2014 or early 2015.
All three of the satellites under construction are scheduled for launch on Russian Proton rockets contracted through International Launch Services of Reston, Va. The Proton rocket returned to flight Sept. 30 with the successful launch of a commercial telecommunications satellite following a July launch failure on a Russian government mission.