Atlas V performed flawlessly its 70th mission and delivered to orbit classified payload for National Reconnaissance Office.
United Launch Alliance, operator of the Atlas V, decided to launch rocket in 401 configuration – payload was covered under 4 m payload fairing, first core stage was not supported with boosters and upper stage was equipped with single RL10C-1 engine. Launch was planned from Vandenberg Air Force Base originally to December 1, 2016 but due the delay of previous mission covering delivering to orbit WorldView-4 satellite, it was necessary to postponed mission to 2017.
Core and upper stage of Atlas V were integrated with NROL-79 payload inside of the SLC-3E in February 2017, after payload was delivered to Vandenberg a February 15. On Monday 27th February, rocket was already at launch pad and last service reviews were performed.
Launch was performed at 17:49:51 UTC from SLC-3E. Rocket performed impressive liftoff and at T+1’20″reached speed of 1 Mach. MaxQ point, when dynamic pressure reaches highest level, was reached ten seconds later. First stage was cut off at T+4’6″ on altitude of 150 km and separated ten seconds before first ignition of centaur upper stage. After another ten seconds payload fairing was separated as rocket reached altitude of 193 km. At that point broadcast was terminated as usual during NROl missions. Until that moment mission was successful, no problems with payload or launch vehicle were reported. United Launch Alliance already confirmed success of NROL-79 mission ended with payload deployment. Next time when we will be able to see another rocket from fleet belonging to ULA is planned for 8th MArch 2017. Delta IV will deliver to orbit WGS-9 satellites for the U.S. Air Force from Space Launch Complex-37 at Cape Canaveral Air Force Station, Florida.