Again full success of United Launch Alliance during next launch contracted for Department of Defense. Weighing 6740 kg next generation communication satellite MUOS-5 was delivered to designated orbit on atop of Atlas V (551) today from Cape Canaveral SLC-41.

Today weather for launch was favorable and probability of launch was at 100%. Atlas V, supported with 5 solid fueled boosters with US Navy MUOS-5 satellite on atop covered with long for over 5 m fairing, was ready for its 63rd mission. Temperature was around 30°C with slight wind from East blowing with speed of 5 m/s.

At 14:23 GMT final tests of the rocket and ground systems were started. Every parameter was carefully checked both for rocket and Centaur second stage. All systems like propulsion, hydraulics, pneumatics, LH2, LO2 and water were ready. One minute later start was confirmed by launch director and countdown started at 14:26 GMT. Punctually at 14:30 GMT Atlas V started to rise over SLC-41. After 40 seconds of flight rocket reached speed of sound and at T+49″ it reached point where dynamic pressure is on highest level during whole flight. At T+1’48” five SRB boosters were separated from core of the rocket. At T+3’27” rocket jettisoned payload fairing during flight performed with speed of 12000 km/h. At T+4’26” RD-180 engine was cut off; fairing of Centaur nozzle was separated together with first stage one second later. At T+4’41” RL-10C engine was started and Centaur upper stage begun its mission. At T+12’28” Centaur shut down its engine for the first time. Upper stage continued ballistic flight over Atlantic Ocean and started its engine again, when was getting close to Africa at T+20’27”, to cut it off again at T+26’14”. Next it continued ballistic flight over South Africa to start engine for the last time at T+2h48’40” during pass over Indonesia. Last burn was finished at T+2h49’38”. MUOS-5 was successfully deployed on at T+2h53’17” (17:23 GMT) on orbit with perigee at 3841.752 km, apogee at 35706.86 km and inclination of 19.10°.

MUOS program started in 2004 when Department of Defense signed worth $7.7 billion contract for five satellites and ground infrastructure. Three contractors were chosen for satellites with two additional for ground segment of system: Lockheed Martin, Boeing, Harris, General Dynamics and Ericsson (last two were responsible for creating ground part of MUOS). First satellite was launched in 2012 and is covering Pacific Ocean region. Next satellite, MUOS-2, was launched in 2013 to cover with its range continental part of USA. MUOS-3 and MUOS-4 were launched in 2015 and are providing communication over Atlantic and Indian Ocean. MUOS-5 was designed as identical, backup satellite and will remain on GEO over Indian Ocean.