After almost three launchless months for United Launch Alliance (ULA), and one of its slowest years on record in terms of overall flight cadence, the Centennial, Colo.-headquartered organization has welcomed rocket hardware for a critical U.S. Space Force mission, targeted for early next spring. ULA CEO Tory Bruno announced yesterday that a 107-foot-long (32-meter) Atlas V Common Core Booster (CCB) and 41-foot-long (12.6-meter) Centaur upper stage had arrived safely at Cape Canaveral Air Force Station, Fla., aboard the company’s RocketShip transport vessel after a journey from the factory in Decatur, Ala.
Teamed with a single solid-fueled booster to form a never-before-tried Atlas V variant, the vehicle will deliver a pair of Geosynchronous Space Situational Awareness Program (GSSAP) satellites into orbit as soon as March 2021 on a Space Force mission designated “USSF-8”.
“#ULARocketShip delivering the #AtlasV booster and Centaur for the #USSF8 mission for the @SpaceForceDoD,” tweeted ULA CEO Tory Bruno late Tuesday evening. “Launch is planned for Spring 2021.”
The USSF-8 mission will carry the fifth and sixth GSSAP birds into geosynchronous orbit, some 22,600 miles (35,900 km) above Earth, to follow on the heels of previous pairs of satellites which rode Delta IV Medium+ boosters in July 2014 and August 2016.
Initially built by Orbital Sciences Corp.—and now Northrop Grumman Corp.—they were based upon the GEOStar-1 satellite “bus”, specially optimized for a range of defense and civil missions from weather and Earth observations to intelligence, surveillance and reconnaissance and from positioning, navigation and timing to tactical communications and reportedly capable of supporting payloads up to 330 pounds (150 kg).
And the specific remit of GSSAP sits within the Space Situational Awareness (SSA) arena. They were designed to support U.S. Strategic Command space surveillance operations as a dedicated Space Surveillance Network (SSN) sensor, as well as providing assistance for the Joint Functional Component Command for Space (JFCC-Space) in its task of more accurately tracking and characterizing human-made objects in orbit.
The GSSAP satellites “drift” above and below the Geosynchronous Earth Orbit (GEO) “belt” and employ advanced electro-optical sensors to observe other objects. This data is expected to enhance the abilities of the U.S. Space Force to understand the geosynchronous environment and develop new safety systems, including collision-avoidance mechanisms.
In March 2014, then-head of Air Force Space Command Gen. William Shelton described GSSAP as nothing less than a “neighborhood watch” system for U.S. satellites. “GSSAP will produce a significant improvement in space object surveillance, not only for better collision avoidance, but also for detecting threats,” Gen. Shelton remarked. “GSSAP will bolster our ability to discern when adversaries attempt to avoid detection and to discover capabilities they may have which might be harmful to our critical assets at these higher altitudes.”
Two such assets are the Advanced Extremely High Frequency (AEHF) fleet of military communications satellites—the most recent of which was launched last March and completed on-orbit testing just last month—and the Space-Based Infrared System (SBIRS), whose fourth geosynchronous-orbiting member flew in January 2018. “One cheap shot against the AEHF constellation would be devastating,” Gen. Shelton noted. “Similarly, with our Space-Based Infrared System, one cheap shot creates a hole in our environment.”
Following the emplacement of the first four GSSAP satellites in orbit, in March 2018 the Air Force selected ULA to launch GSSAP-5 and GSSAP-6 as part of a $351.8 million contract for two Air Force Space Command missions originally designated AFSPC-8 and AFSPC-12. Following the redesignation of Air Force Space Command and the formal creation of the U.S. Space Force last December, the missions henceforth became known as USSF-8 and USSF-12.
With yesterday’s arrival of the rocket hardware at the Cape for USSF-8, the Atlas V CCB will head for the Atlas Spacecraft Operations Center (ASOC) for initial receiving checks and horizontal processing and the Centaur will move into the 30-story Vertical Integration Facility (VIF) at Space Launch Complex (SLC)-41 to commence installation of its inter-stage adapter, payload fairing base segments and support ring.
Early next year, the Atlas V CCB will be hauled a distance of 4 miles (6.4 km) atop a semi-truck to the VIF for the Launch Vehicle On Stand (LVOS) milestone. There it will be craned into a vertical configuration and positioned atop the Mobile Launch Platform (MLP). This will be followed by the addition of the Centaur and a single solid-fueled rocket booster.
With a 16-foot-diameter (5-meter) payload fairing, a single-engine Centaur and a single booster, this will be the first launch of a new variant of the Atlas V, known as the “511”. Like its smaller cousin, the Atlas V 411—which carries a slightly smaller payload fairing, measuring 13 feet (4 meters) across, and which saw service most recently in February 2020 to launch Solar Orbiter—the 511 will exhibit an unusual “sideways-flying” perspective as it “slides” upward from the pad.
Steering actuators on the Atlas V’s RD-180 engine will counteract the asymmetrical thrust from the single solid and ensure that the rocket flies straight and true, but it will undoubtedly offer a disconcerting sight for spectators. And as Mr. Bruno previously noted, all Atlas Vs have their own nicknames. With the 411 already dubbed “Slider”, the moniker for the bigger 511 is “Super Slider”.
Elsewhere, three other Atlas V rockets are at various stages of their own processing for flights later this fall and early in 2021. The CCB and Centaur for the highly secretive NROL-101 mission, flying on behalf of the National Reconnaissance Office, arrived on the Space Coast in early July and were joined a few weeks later by three of Northrop Grumman’s upgraded Graphite Epoxy Motors, known as the “GEM-63”, on account of their 63-inch (1.6-meter) cases.
The GEM-63 is being test-flown on successive Atlas V missions to validate its performance ahead of next year’s debut of the “extended” GEM-63XL which will help to power ULA’s next-generation Vulcan-Centaur heavylifter. The three GEM-63s were attached to the Atlas V last month, with launch from SLC-41 anticipated later this fall.
Next up after NROL-101, possibly as soon as the first week of January, an Atlas V N22—flying only its second mission with a Dual-Engine Centaur (DEC) upper stage—will launch from SLC-41 for the second uncrewed test of Boeing’s CST-100 Starliner vehicle to the International Space Station (ISS). The Atlas V and Centaur hardware for this mission has been at the Cape since June 2019, having originally been earmarked to fly the first crewed test flight. That changed following last December’s troubled uncrewed test and it has since been pressed into service for this critical second uncrewed test.
And as early as February, the most powerful operational member of the Atlas V fleet (the “551”, equipped with five solid-fueled boosters) will deliver the Space Test Program (STP)-3 mixed-payload suite to orbit. Contracts to fly STP-3 were signed between ULA and the Air Force back in June 2017.
It includes the STPSat-6 primary payload, built by Northrop Grumman, which will serve as a testbed for a number of experiments, including the Space and Atmospheric Burst Reporting System (SABRS)-3 to provide nuclear detonation detection and space environment measurements. Also aboard is NASA’s Laser Communications Relay Demonstration (LCRD) and a number of other experimental technologies.