MUOS-5 failed to reach designated orbit

Last from series of five next generation communication satellites for U.S. Navy, MUOS-5, failed to reach its designated orbit. Its present position is far for about 20000 km from place where it should start its operational life.

MUOS-5 was launched on June 24, 2016 on atop of Atlas V (551 configuration) rocket from Cape Canaveral SLC-41. It was last satellite from MOUS series and its main application was to remain as backup spacecraft over Indian Ocean and replace in case of problems one from previous four satellites. Now it seems that backup satellite will need replacement.

MUOS-5 was delivered by Atlas V to transfer orbit with apogee at 35750 km, perigee at 3827 km and inclination of 19.1°. Using its propulsion, satellite should move to GEO orbit. Apogee Kick Motor, Japanese IHI BT-4 bi-fueled (N2H4/MON-3) engine with 450 N of thrust seemed to operate correctly and satellite was gradually approaching to GEO orbit during following days. On July 3, 2016, satellite should already reached position over Pacific; on GEO circular orbit with altitude on 35398 km. Unfortunately MUOS-5 on July 3 was not in designated position. Satellite spotters lost MUOS-5 on July 5 and first gossips about problems with worth $340 million satellite started to appear. U.S. Navy press office announced in statement on July 8, 2016, that MUOS-5 failed to reach GEO orbit planned for testing and remains on medium orbit. MUOS-5 is on orbit with inclination at 9.8° with apogee at 35703 km and perigee at 15242 km. No further details were announced, but according to U.S. Navy, specialists are still working to resume transfer maneuver (surely along with engineers from Lockheed Martin, which was manufacturer of the MUOS-5). Observation of the satellite confirmed that it is probably in controlled spin flight (it generates flashes with regular intervals); it confirms partially that attitude control system (based on reaction wheels and 18 thrusters) is working correctly and it is still possible to continue its journey.

On picture above: Naval Computer and Telecommunications Area Master Station Pacific in Wahiawa, Hawaii. Installing one of three dishes, which were designated to perform first in-orbit tests of MUOS-5.