United Launch Alliance has begun final preparations for its Atlas V vehicle ahead of launching a national security payload for the National Reconnaissance Office from Cape Canaveral Air Force Station in Florida.
ULA said Friday that NROL-101 will launch from Cape Canaveral's Space Launch Complex-41 on Tuesday at 5:58 p.m. EST.
NROL-101 will serve as ULA's first mission using Northrop Grumman's Graphite Epoxy Motors 63 boosters that use solid propellants designed to generate 1.8M pounds of thrust at liftoff.
Aerojet Rocketdyne is the manufacturer of the RL10C-1 engine for the Atlas V rocket's Centaur upper stage.
Gary Wentz, vice president of government and commercial programs at ULA, said NROL-101 serves as ULA's 29th mission for the NRO as well as the 17th NRO mission that will use Atlas V.
The Atlas V vehicle for NROL-101 will have a 531 configuration, which the U.S. Space Force also used to launch the three initial Advanced Extremely High Frequency satellites.
Atlas V 531 will send a pair of C-band satellite buses to orbit for an SES mission in 2022.