spacetoday.net: Atlas 5 launches AEHF-6

Posted: Fri, Mar 27, 2020, 2:13 PM ET (1813 GMT)
Atlas 5 launch of AEHF-6 (ULA)

A United Launch Alliance Atlas 5 successfully launched a military communications satellite Thursday afternoon. The Atlas 5 551 lifted off from Cape Canaveral at 4:18 pm EDT (2018 GMT), nearly 90 minutes later than planned after a problem with a ground system hydraulic pump controller halted the countdown in its final minute. The payload, the Advanced Extremely High Frequency (AEHF) 6 satellite, was deployed from the rocket's Centaur upper stage several hours later. The Lockheed Martin-built satellite completes the AEHF system, which provides protected military communications. The launch also carried a cubesat secondary payload, TDO-2, with payloads that will test optical calibration and satellite laser-ranging technologies for space domain awareness.