United Launch Alliance (ULA) will not launch its next Atlas V until 25 March, following yesterday’s announcement of a firm date for the second uncrewed test flight of Boeing’s CST-100 Starliner to the International Space Station (ISS) and a delay to the Department of Defense’s Space Test Program (STP)-3 mission for “launch readiness” evaluations. Both are expected to fly from storied Space Launch Complex (SLC)-41 at Cape Canaveral Space Force Station, Fla. A new launch date for STP-3 has not been revealed.
Flying only five missions in 2020—one of its “lightest” years on record, in terms of launch cadence—ULA successfully lofted the Solar Orbiter mission to investigate the Sun at high heliographic latitudes last February, followed by the sixth and last Advanced Extremely High Frequency (AEHF) military communications satellite to Geostationary Earth Orbit last March. In mid-May, it sent the X-37B Orbital Test Vehicle (OTV) mini-shuttle on its sixth long-duration clandestine voyage for the U.S. Space Force and last July boosted the long-awaited Perseverance rover and attached Ingenuity helicopter toward Mars.
Sadly, the second half of 2020 proved distinctly more troubled, as ULA’s triple-barreled Delta IV Heavy booster—making its first flight in over a year, as ULA phases out its entire Delta product line by the middle of this decade—was hit by multiple technical and weather-related delays in its bid to get the highly secretive NROL-44 payload launched for the National Reconnaissance Office.
Postponed repeatedly from August, the mission finally got airborne Launched finally in December, the mission finally got airborne in the second week of December. Added to the list was another flight in November, laden with the classified NROL-101 payload for the National Reconnaissance Office, whose Atlas V was equipped for the first time with Northrop Grumman Corp.’s upgraded GEM-63 solid-fueled motors.
As a direct consequence of the delays, other missions planned for 2020 correspondingly slipped into 2021, including NROL-82 from Vandenberg Air Force Base, Calif.—also slated to ride a Delta IV Heavy—and the second uncrewed test flight of Boeing’s CST-100 Starliner to the space station, atop an Atlas V.
This placed ULA in pole position for 2021 to mark a resurgence in operations, with two Delta IV Heavy missions slated to fly the classified NROL-82 and NROL-91 payloads out of Vandenberg, multiple Atlas V launches in support of U.S. Government, scientific and commercial objectives and the maiden voyage of the Vulcan-Centaur heavylifter to send Astrobotic Technology’s Peregrine lunar lander to the surface of the Moon.
Opening 2021’s launch salvo was expected to be an Atlas V in its most-powerful “551” configuration—equipped with a 17-foot-diameter (5-meter) payload fairing, five strap-on, solid-fueled boosters and a single-engine Centaur upper stage—to deliver the Space Test Program (STP)-3 payload into orbit from the Cape’s SLC-41 in late February.
Contracts worth $191 million to launch STP-3 were awarded to ULA back in June 2017, under the Air Force’s Phase 1A procurement strategy, with initial expectations that the mission would fly within the June-August 2019 timeframe, although it has since met with significant delay. The payload’s primary space vehicle is STPSat-6, the design and integration contracts for which were awarded to Orbital Sciences Corp. (now Northrop Grumman Corp.) back in February 2017.
Based upon the A500 satellite “bus”, the geostationary-bound STPSat-6 will house nine payloads for the Department of Defense, the National Nuclear Security Administration (NNSA) and NASA to “operationally demonstrate advanced communication capabilities, collect space weather data and support nuclear detonation detection in the Earth’s atmosphere or in near space”.
Leading those payloads in the NNSA’s third Space and Atmospheric Burst Reporting System (SABRS)-3, built by Los Alamos National Laboratory (LANL) in Los Alamos, N.M., which is part of an ongoing effort to replace neutron, gamma-ray and particle detectors flown aboard Defense Support Program (DSP) satellites from the 1970s through the 1990s. It augments the optical, radio frequency, X-ray and particle sensors of the Global Burst Detector (GBD) payload aboard in-service Global Positioning System (GPS) satellites.
Also aboard STPSat-6 is the Laser Communication Relay Demonstration (LCRD), built by NASA’s Goddard Space Flight Center (GSFC) in Greenbelt, Md., which provides an end-to-end optical relay, capable of sending and receiving data from orbiting spacecraft to ground control stations.
“This evolution to more internet-like communications will reduce the amount of processing required before data can be sent to science and mission operations centers,” it was reported. “LCRD will demonstrate the robust capabilities of optical communications.” Specific benefits from optical communications systems include lower sizes, masses and power requirements and bandwidths 10-100 times greater than traditional radio frequency systems.
Seven additional experiments from the Department of Defense’s Space Experiments Review Board are also assigned to fly aboard STPSat-6. One of them is thought to be the NNSA’s Space and Endo-Atmospheric NuDet Surveillance Experiment (SENSER), which seeks to reduce the developmental risks for future Nuclear Detection sensors by testing and evaluating critical technologies in the space environment, ahead of production and integration into next-generation systems.
Also part of the STP-3 mission is an Integrated Propulsive Evolved Expendable Launch Vehicle (EELV) Secondary Payload Adapter (IP-ESPA), capable of holding up to six small payloads. Early last month, this complete payload—formally known as the Long Duration Propulsion ESPA-1 (LDPE-1)—was delivered from Northrop Grumman’s Gilbert, Ariz., facility to Cape Canaveral Space Force Station, Fla., for final processing.
“The satellite will be processed at the Astrotech Space Operations Facility in Florida to ensure full functionality and prepare for propellant loading,” it was noted. “At the completion of these activities, the satellite will be mated to the STPSat-6 satellite and the two space vehicles will be integrated to a United Launch Alliance Atlas V 551 launch vehicle.”
However, on Monday it was reported by ULA that the STP-3 mission—expected to fly as soon as 26 February—was being postponed, “to enable the customer to evaluate the launch readiness of the [STPSat-6] spacecraft”. No further details were provided and a new launch date for the already-long-delayed mission is unclear. What is clear, however, is that the next mission on ULA’s books will be the second uncrewed Orbital Flight Test (OFT-2) of Boeing’s troubled CST-100 Starliner to the International Space Station (ISS), whose own launch from SLC-41 has moved four days to the left, from the original target of 29 March to settle upon a new No Earlier Than (NET) date of 25 March.
Flying atop an Atlas V equipped for only the second time with a Dual-Engine Centaur (DEC) upper stage, the mission will attempt a second uncrewed visit to the ISS to fulfil a critical Commercial Crew transportation Capability (CCtCap) requirement, following the troubled flight of OFT-1 in December 2019. As outlined by AmericaSpace’s Mike Killian last summer, the CST-100 Starliner suffered a pair of software coding errors and an unexpected loss of space-to-ground communications, which conspired to preclude a docking at the space station and forced a premature return to Earth.
Earlier this month, Boeing reported that it had formally requalified the spacecraft’s flight software, ahead of OFT-2. A series of static and dynamic tests in the Avionics and Software Integration Lab (ASIL) in Houston, Texas, served to validate the performance of the software in tandem with the recommended flight hardware across “hundreds of cases, ranging from single-command verifications and comprehensive end-to-end mission scenarios with the core software”.
In announcing that the OFT-2 launch date has moved to the left, NASA explained that “an opening on the Eastern Range”, together with the readiness of both the Atlas V, steady progress on the hardware and software “and an International Space Station docking opportunity” had aided the move.
A 25 March launch will, however, create an undesirable period of more than 3.5 months between flights by ULA, following its most recent mission with the long-delayed NROL-44 in December. Following OFT-2, other missions with firm definitive launch dates in 2021 include Landsat-9 in September and the Lucy asteroid explorer in October. Assuming that OFT-2 flies without significant anomalies, a Crewed Flight Test (CFT) of the CST-100 Starliner—carrying NASA astronauts Barry “Butch” Wilmore, Nicole Mann and Mike Fincke—may launch later this summer.
Other missions include the fifth geostationary element of the Space-Based Infrared System (SBIRS), the next Geostationary Operational Environmental Satellite (GOES-T), a pair of dedicated U.S. Space Force payloads and the two Delta IV Heavy flights out of Vandenberg.