**Launch dates and times are subject to change** A United Launch Alliance Atlas 5 rocket will launch the fourth Advanced Extremely High Frequency (AEHF) satellite. Built by Lockheed Martin, this U.S. military spacecraft will provide highly-secure communications. The rocket will fly in the 531 vehicle configuration with a five-meter fairing, three solid rocket boosters and a single-engine Centaur upper stage. Delayed from Dec. 15 and Jan. 26.
**Delayed from Dec.15, Jan. 26 and May 4**