ULA Successfully Launches Next Generation Communication MilSat

This afternoon at 2:42 p.m. EDT a United Launch Alliance Atlas V successfully launched the Advanced Extremely High Frequency (AEHF-2) satellite for the Air Force. The satellite is the second of the next generation constellation of military communications satellites to be used by all branches of the service which will result in a 10 fold increase in capability.

The first four AEHF satellites are being built by Lockheed Martin with Northrop Grumman building and integrating the payloads. The fiscal year 2012 budget includes procurement of more parts to start work on AEHF-5 and AEHF-6 to complete the constellation.

The overall AEHF system has three segments:

- Space segment - comprised of an integrated constellation of Milstar and AEHF satellites.

- Mission Control segment - includes fixed and mobile telemetry, tracking, and commanding sites; fixed and transportable communication planning elements; and the common user interface with the Space Ground-Link Subsystem and the Unified S-Band capability.

- Terminal (or User) segment - includes ground-fixed, ground-mobile, man-portable, transportable, airborne, submarine, and shipboard configurations.

Atlas V 531 Launch vehicle expanded view.

The first satellite in the new constellation, AEHF-1 now known as USA-214, was launched by an Atlas V rocket on August 14, 2010 from Space Launch Complex 41 at the Cape Canaveral Air Force Station.

Although the launch successfully placed the satellite into a supersynchronous-apogee transfer orbit, the satellite vehicle's Liquid Apogee Engine failed to raise the orbit after 2 attempted burns. To solve the problem Aerojet monopropellant thrusters were used to raise the perigee and the Aerojet Hall Thrusters provided several hundred propulsive burns, adjusting both the apogee and perigee until AEHF-1 arrived at its intended location.

The next launch for AEHF-3 is scheduled no earlier than Q3, 2013 according to the Air Force.

Please follow SpaceRef on Twitter and Like us on Facebook.