PARIS — Mobile satellite services provider momentum-wheel problems, according to the satellites’ builder and launch services provider.will launch its third batch of six second-generation satellites Dec. 28, three weeks later than planned, to give satellite builder time to replace one of the six because of suspected
Covington, La.-based Globalstar said it expects to launch the last batch of six satellites in the first half of 2012. Both launches will be aboard Russian Soyuz rockets operated from Russia’s Baikonur Cosmodrome in Kazakhstan, with launch services provided by the French-Russian Starsem company, which is part-owned by Europe’slaunch consortium of Evry, France.
The second-generation satellites, plus some of the newer spacecraft from Globalstar’s first-generation constellation, together will permit Globalstar to reinstate its two-way voice service. Most of the first-generation satellites have been unable to deliver voice traffic since suffering an on-board failure likely related to radiation exposure. The decline in two-way voice service, which is Globalstar’s most profitable offering, began in early 2007.
The first two batches of second-generation satellites were launched in October 2010 and July of this year. A few of them have suffered a momentum-wheel anomaly. The planned Dec. 5 launch of the third batch was held up to permit prime contractor Thales Alenia Space of France and Italy to replace one of the satellites planned for the December launch with a satellite that had been scheduled for the last batch.
Thales Alenia Space and Globalstar have said they are developing a software upload to be able to operate the second-generation satellites for their full 15-year service lives even if they lose the use of two of their four momentum wheels.