A Rare Atlas V 551 Launch Deploys AFSPC-11 Payloads

A United Launch Alliance (ULA) Atlas V successfully deployed both Air Force Space Command 11 (AFSPC-11) payloads over the weekend. The mission utilized the rarely used 551 Atlas V configuration, the most powerful launch vehicle ULA offer.

The Atlas V 551 launched from Cape Canaveral Air Force Station in Florida at 23:13 GMT (19:13 local time) on April 14.

An Atlas V 551 launches with the AFSPC-11 payloads aboard.
AFSPC-11 Launches from Cape Canaveral Air Force Station | Image Credit: ULA

The AFSPC-11 payloads have been confirmed as the CBAS (Continuous Broadcast Augmenting SATCOM) and EAGLE (EELV Secondary Payload Adapter (ESPA) spacecraft. As the mission was on behalf of the US military, there has been no confirmation that the satellites were successfully brought online. However, ULA has confirmed that both payloads successfully separated from the Atlas V upper stage.

CBAS is a communications satellite designed to be used to relay communications between senior leaders and commanders in the field. Apart from a broad description, no additional details are known about the CBAS satellite. Both the launch provider, ULA and the manufacturer have opted not to disclose either the satellite’s operating frequencies or its designated Geostationary Orbit.

The EAGLE satellite was launched between the Atlas V payload adapter and the much larger CBAS satellite above. Manufactured by Orbital ATK, Eagle features five slots for Space Test Program-sponsored payloads. The slots serve as a testbed for several technology demonstrations including the Hypertemporal Imaging Space Experiment (HTI-SpX), Inverse Synthetic Aperture Ladar (ISAL) and the ARMOR resilient spacecraft bus development experiment.

Saturday’s launch was the 77th Atlas V launch and the fourth ULA launch of 2018. The last mission the provider supported launched the SBIRS GEO Flight 4 satellite aboard an Atlas V rocket. The mission was the provider’s second national security launch within seven days.

Image Credit: ULA

Andrew Parsonson is a space enthusiast and the founder of Rocket Rundown. He has worked as a journalist and blogger for various industries for over 5 years and has a passion for both fictional and real-life space travel. Currently, Andrew is the primary writer for Rocket Rundown as we look to expand our reach and credibility.