A busy plate of United Launch Alliance (ULA) missions for the remainder of 2021 continues to take shape, following Friday’s completion of stacking operations of a Mighty Atlas V booster at Space Launch Complex (SLC)-41 at Cape Canaveral Space Force Station, Fla. The final topping-off of the rocket involved installation of the Extra-Extended Payload Fairing (XEPF), with launch targeted for 1:35 p.m. EDT on Monday, 17 May. The mission will deliver the fifth geostationary element of the U.S. Space Force’s Space-Based Infrared System (SBIRS GEO-5) to orbit and marks the eighth flight of an Atlas V in its “421” configuration, equipped with a 13-foot-wide (4-meter) fairing, two strap-on solid-fueled boosters and a single-engine Centaur upper stage.
The XEPF is a two-piece (or “bisector”) shell-like fairing, which affords vibrational, acoustic and aerodynamic protection for SBIRS GEO-5 during the launch and ascent phase; it will be jettisoned in the rarefied high atmosphere to expose this critical early-warning satellite to the space environment. Standing 45 feet (13.7 meters) tall, the XEPF comprises an aluminum skin/stringer construction, with vertical split-line longerons. After integration of the XEPF, the Atlas V—which is set to embark on its 87th mission—rises a towering 194 feet (59.1 meters) above the Mobile Launch Platform (MLP).
As previously reported by AmericaSpace, the flight hardware for the Atlas V arrived safely in Port Canaveral on 1 April. The 107-foot-long (32.6-meter) Common Core Booster (CCB) for the rocket, together with its 41-foot-long (12.6-meter) Centaur upper stage, departed ULA’s manufacturing site in Decatur, Ala., on 23 March and traveled via the Mississippi River and the Gulf of Mexico, aboard the R/S RocketShip transport vessel. Shortly after its arrival on the Space Coast, the Centaur was transferred to ULA’s facilities for flight preparations, whilst the Atlas V CCB headed via flatbed truck to the ordnance bay in the Atlas Spaceflight Operations Center (ASOC).
Here it was put through initial preparations and declared ready to commence stacking operations for launch. Vertical integration of the two-stage rocket with its two Aerojet Rocketdyne-provided AJ-60A solid-fueled boosters began on 21 April in the cavernous interior of the VIF, when the Atlas V was hoisted upright on the MLP. This completed the Launch Vehicle On Stand (LVOS) milestone and officially marked the start of the SBIRS GEO-5 launch campaign.
Late last month, the two AJ-60A boosters—each standing 55.7 feet (17 meters) tall—were installed on opposite sides of the Atlas V CCB. With a combined propulsive yield of just under 760,000 pounds (340,000 kg), they will afford the stack more than half of its energy at liftoff. This will mark the 40th use of AJ-60-class boosters on Atlas V missions since July 2003. The most recent flight of an Atlas V with the boosters occurred during last summer’s launch of the Perseverance mission to Mars.
ULA intends to gradually retire its existing stock of AJ-60As over the coming months, in favor of Northrop Grumman’s GEM-63 booster, which first flew during last November’s NROL-101 mission. “They are being cut into our launches using a pre-defined schedule,” ULA’s Heather McFarland told AmericaSpace of the upgraded boosters, “with the complete transition to GEM-63s in the near future.”
With two solids, a 13-foot-diameter (4-meter) fairing and a single-engine Centaur, the Atlas V for SBIRS GEO-5 is designated “421” and will mark the eighth use of this particular configuration of the rocket since October 2007. It most recently saw service for the October 2017 launch of NROL-52 for the National Reconnaissance Office. In addition to a pair of missions for the NRO, other past customers have included two Wideband Global Satcoms (WGS) for the U.S. Space Force, two commercial communications satellites and NASA’s 2015-launched Magnetospheric Multiscale Mission (MMS). All told, the 421 configuration can lift up to 30,800 pounds (14,000 kg) to low-Earth orbit or up to 15,200 pounds (6,890 kg) to Geostationary Transfer Orbit (GTO).
SBIRS GEO-5 completed an ahead-of-schedule construction and testing campaign last October, with the elimination of unnecessary programmatic oversight and reporting, a restructured test program and a streamlined production schedule having enabled Lockheed Martin Corp. to finish SBIRS GEO-5 in only five years. Described as a “global guardian” for ballistic missile detection and defense, it is the fifth geostationary element of an upgraded set of space-based infrared “eyes” and follows four previous missions also launched atop Atlas Vs between May 2011 and January 2018.
SBIRS forms part of a multi-billion-dollar Pentagon effort to replace the earlier Defense Support Program (DSP) network of early-warning satellites, whose own ancestry extends back to the 1970s. It is expected to enable the United States’ space surveillance needs for the next two decades, with focuses including advanced early warning, missile defense and battlespace characterization. In its final form, it will comprise six GEO satellites at geostationary altitude, together with adjunct sensors aboard the HEO-1 and HEO-2 satellites, which were inserted into highly-elliptical orbits back in June 2006 and March 2008.
The successful launch of SBIRS GEO-1 in May 2011 marked the culmination of a long and tortured development process, which saw costs balloon by over 400 percent from an estimated $4 billion to over $17 billion. According to General Accounting Office (GAO) auditors, as reported by Defense Industry Daily in February 2013, the program suffered from “immature technologies, unclear requirements, unstable funding, underestimated software complexity [and] poor oversight”.
In the meantime, a $284.4 million contract for the purchase of long-lead items for GEO-5 and GEO-6 were awarded in March 2013, ahead of the definitive $1.86 billion deal between the Air Force and Lockheed Martin in June 2014 to fabricate both satellites. At the time of the award, it was noted that the contract formed part of “a thoughtful acquisition strategy aimed at further reducing cost and cycle time”. In particular, more than a billion dollars’ worth of saving were achieved through “block-buy” contracting practices and the elimination of unnecessary program oversight and reporting, a restructured test program and a streamlined production schedule.
In September 2017, both the GEO-5 and GEO-6 satellites wrapped up their Critical Design Review (CDR) at Lockheed Martin’s Sunnyvale, Calif., facility, with Col. Dennis Bythewood, director of SMC’s Remote Sensor Systems Directorate, praising the “resiliency” of the program. Upon the completion of the CDR, both satellites moved directly into manufacturing and integration. In February 2019, ULA was awarded a $441.6 million contract to launch three payloads—including SBIRS GEO-5 and GEO-6—with an expectation that the GEO-5 element would fly atop an Atlas V from Space Launch Complex (SLC)-41 at Cape Canaveral Air Force Station, Fla., as early as March 2021.
GEO-5 pressed smoothly through Thermal Vacuum (TVAC) testing last summer, which constituted a “major milestone” in readying the satellite for final assembly. “Lockheed Martin Space overcame COVID-19-related challenges,” noted the Air Force, “to maintain assembly and test operations with minimal impacts.” Following its completion last fall, SBIRS GEO-5 was delivered aboard a C-5M Super Galaxy transport aircraft from Moffett Airfield in California to the Space Coast in March.
The design of SBIRS GEO-5 marks the inaugural use of Lockheed Martin’s heavily modernized LM2100 “Combat Bus”, carrying twin solar arrays and a powerful communications and imaging payload. In what has been described as a “technical refresh update”, their newer components and more modern electronics are expected to achieve a boost in capability and reliability.
The new SBIRS benefits from 26 enhancements, ranging from improved cyber-hardening, greater spacecraft power, propulsion and electronics, common components to streamline manufacturing and a flexible design architecture. According to Lockheed Martin, the LM2100 Combat Bus architecture will also form the baseline for the upcoming Next-Generation Overhead Passive Infrared (Next-Gen OPIR) Block 0 satellites and the Global Positioning System (GPS) Block III Follow-On series, both of which are expected to enter service around the middle of this decade.
Led by the Infrared Space Systems Directorate at the Air Force’s Space and Missile Systems Center (SMC) at Los Angeles Air Force Base in Los Angeles, Calif., the SBIRS GEO satellites and their ground systems are operated by the 460th Space Wing at Buckley Air Force Base in Aurora, Colo. “SBIRS’ role as an ever-present, on-orbit guardian against global ballistic missile threats has never been more critical,” said Tom McCormick, Lockheed Martin’s vice president for OPIR Systems. “In 2019 alone, SBIRS detected nearly one thousand missile launches, which is about a two-fold increase in two years.”
In addition to SBIRS GEO-5, the Atlas V will also be transporting a pair of “Multi-Manifest Satellite Vehicles” on behalf of the Multi-Manifest Office of the Space and Missile Systems Center (SMC), headquartered at Los Angeles Air Force Base in Los Angeles, Calif., in partnership with the U.S. Air Force Academy. Designated “TDO-3” and “TDO-4”, the two 12U CubeSats—each measuring approximately 7.8 x 7.8 x 13.4 inches (20 x 20 x 34 cm)—are set to be deployed shortly before SBIRS GEO-5 itself.
Little has been revealed about their precise objectives, with ULA noting only that “a multi-manifest mission set allows more capability to be placed on-orbit”, with the eventual goal of “providing more critical capabilities to the warfighter”. Two earlier missions with similar designators, TDO-1 and TDO-2, rode aboard Atlas Vs in August 2019 and March 2020, alongside the second-to-last and last Advanced Extremely High Frequency (AEHF) military communications satellites. In the case of TDO-2, the small satellite was released from its perch at the aft-facing end of the Centaur upper stage about a half-hour after liftoff. The two missions focused upon a range of orbital debris tracking and space domain awareness functionality tasks.
Coming only three weeks since the spectacular 26 April launch of a giant Delta IV Heavy booster from Vandenberg Air Force Base, Calif.—laden with the classified NROL-82 payload for the National Reconnaissance Office—an otherwise flightless spring for ULA seems to be giving way to a busy second half of the year. Following SBIRS GEO-5, a long-delayed mission in support of Space Test Program (STP) objectives is presently targeted for June, with the second uncrewed Orbital Flight Test (OFT-2) of Boeing’s CST-100 Starliner to the International Space Station (ISS) now formally scheduled for 30 July.
Heading into the late summer and fall, a pair of classified U.S. Space Force missions—USSF-8 in August on an Atlas V in its never-before-flown “511” configuration and USSF-12 before year’s end—will be joined in December by the latest Geostationary Operational Environment Satellite (GOES-T) for the National Oceanic and Atmospheric Administration (NOAA) and in October by NASA’s ambitious, decade-long Lucy mission to explore a half-dozen Trojan-class asteroids. All of these flights will originate from Cape Canaveral Space Force Station, with the launch of Landsat-9 targeted for September from Vandenberg.
It remains to be seen if the Crew Flight Test (CFT) of the CST-100 Starliner will fly this year. In recent months, there has been much speculation that Commander Barry “Butch” Wilmore, Pilot Nicole Mann and Joint Operations Commander (JOC) Mike Fincke are not likely to fly their CFT mission until about six months after OFT-2, which would place their launch sometime in the spring 2022 timeframe. In any case, as ULA’s manifest for the second half of 2021 gathers pace, it looks increasingly probable that the recent Delta IV Heavy launch will be followed by as many as eight Atlas Vs and perhaps the maiden voyage of the Vulcan-Centaur heavylifter before New Year’s Eve.