‘Big Slider’ Atlas V launches the USSF-8 mission
United Launch Alliance’s Atlas V rocket lifts off in a “511” configuration for the USSF-8 mission. Credit: Theresa Cross / Spaceflight Insider
United Launch Alliance flew its first and only “Big Slider” Atlas V rocket to send two satellites into space for the United States Space Force.
Launching in a “511” configuration, ULA’s Atlas V rocket sported a five meter fairing with a single solid rocket motor. Liftoff occurred at 2 p.m. EST (19:00 UTC) Jan. 21, 2022, from Space Launch Complex 41 at Cape Canaveral Space Force Station in Florida.
ULA CEO Tory Bruno explained in a pre-launch company video that this unique configuration was needed to provide just the right amount of thrust to deliver the two spacecraft for the USSF-8 mission directly into a near-geosynchronous orbit.
Bruno also said it was known as the “Big Slider” because of how it power-slides off the pad because of the asymmetric torque produced by the one solid rocket motor. During the course of the flight, the Atlas booster core’s RD-180 engine has enough control authority to compensate for that torque.
This is to be the only Atlas V to fly in the “511” configuration because the vehicle is set to be replaced by the company’s Vulcan rocket, which is expected to debut later this year or early next year. Just over two dozen Atlas V rocket launches remain.
ULA’s Atlas V 511 soars toward space. Credit: Theresa Cross / Spaceflight Insider
A chart showing the nicknames of the various Atlas V variants. Credit: United Launch Alliance
The two satellites orbited for the USSF-8 mission were for the Geosynchronous Space Situational Awareness Program: GSSAP-5 and GSSAP-6. The spacecraft were deployed about 6 hours, 35 minutes and 6 hours, 45 minutes, respectively, after three separate engine burns of the Centaur upper stage.
These identical spaced-based satellites are designed to dutifully watch for optimal satellite positioning in the geosynchronous orbit to help enhance navigation, and to alert all spacefaring nations of other space objects approaching that could cause an operational threatening situation.
The information gathered from GSSAP-5 and GSSAP-6 is also expected to also provide for “timely and accurate orbital predictions” according to the ULA’s latest press release on the launch, strengthening knowledge of collision avoidance and flight safety in the space theater.
These satellites are also capable of adjusting their orbits as needed to image and approach other spacecraft.
Features of these satellites developed by the Air Force and Orbital Sciences Corporation, now Northrop Grumman, include many characteristics declassified in 2014 and two deployable solar arrays to generate power for the spacefaring duo.
This was the third mission of the Geosynchronous Space Situational Awareness Program. The previous two launched via Delta IV Medium rockets on July 28, 2014, and Aug. 19, 2016, with two satellites each.
Video courtesy of United Launch Alliance
Theresa Cross
Theresa Cross grew up on the Space Coast. It’s only natural that she would develop a passion for anything “Space” and its exploration. During these formative years, she also discovered that she possessed a talent and love for defining the unique quirks and intricacies that exist in mankind, nature, and machines. Hailing from a family of photographers—including her father and her son, Theresa herself started documenting her world through pictures at a very early age. As an adult, she now exhibits an innate photographic ability to combine what appeals to her heart and her love of technology to deliver a diversified approach to her work and artistic presentations. Theresa has a background in water chemistry, fluid dynamics, and industrial utility.
