Kicking off United Launch Alliance’s ambitious 2016 with as many as 15 launches planned for the U.S. military, intelligence community, NASA and commercial clients, an Atlas 5 rocket will thunder to orbit Friday to deploy the last satellite in the current generation of GPS navigation spacecraft.

The first of up to seven missions planned on United Launch Alliance’s Atlas and Delta rocket fleets this year is scheduled for Saturday from California’s Central Coast, when a Delta 4-Heavy is set for blastoff on a spy satellite delivery flight delayed a month to troubleshoot a hydrogen fuel leak in a booster.

A $1.8 billion U.S. Air Force communications satellite rode a United Launch Alliance Atlas 5 rocket into orbit Wednesday from Cape Canaveral, joining three similar craft perched more than 22,000 miles above Earth to ensure government leaders can remain in contact with military commanders in the worst-case scenario of nuclear war.