Oct. 16 (UPI) -- United Launch Alliance launched the fourth Advanced Extremely High Frequency satellite into space for the U.S. Air Force early Wednesday.
AEHF-4 launched atop an Atlas V rocket from Cape Canaveral Air Force Station in Florida at 12:15 a.m. EDT.
The 197-foot rocket was rolled out to the launch pad Monday afternoon to prepare for take-off.
The Atlas V 551 variant was used for the launch, ULA said, which includes a kerosene-fueled common core booster and five solid rocket motors strapped on, as well as the Centaur upper stage and five-meter-diameter payload fairing.
The first three AEHF satellites were launched in 2010, 2012 and 2013, with the system being declared at initial operational capability in 2015.
The AEHF system is intended to be a joint-service communications system that provides "survivable, global, secure, protected and jam-resistant communications for high-priority military ground, sea and air assets." It is expected to provide 10 times the coverage of the 1990s-era system it replaced.
Wednesday's launch, the 131st for ULA and 79th for an Atlas V rocket, can be viewed on ULA's YouTube channel.