EL SEGUNDO, Calif. -- The successful U.S. Space Force USSF-44 mission launch was notable for several reasons: it was the first National Security Space Launch (NSSL) on a Falcon Heavy rocket and the first Falcon Heavy launch since June of 2019.
But Dr. Walter Lauderdale, Space Systems Command's chief of Falcon Systems & Operations and USSF-44 Mission director, said what made the launch unique “and a sign of what’s to come,” was the fact that the Nov. 1 launch included a variety of payloads from multiple commercial and government mission partners, all successfully deployed into geosynchronous orbit (GEO).
“USSF-44 highlighted the kinds of ways we need to work together to accomplish that objective,” Lauderdale said. “We will see more of that – we need to be learning from these campaigns and taking those ‘lessons learned’ as an entire command and putting it into what we do for the future, to make sure we’re ready for 2026.”
SSC and its industry and mission partners have maintained a 100 percent mission success rate for launches conducted under the NSSL program since 2003, and USSF-44 continued that record.
USSF-44 launched from NASA’s Kennedy Space Center in Florida, using a SpaceX Falcon Heavy rocket. The rocket’s two side boosters were recovered on land and will be reused for the USSF-67 launch in January 2023, Lauderdale said.
The Falcon Heavy can lift nearly 64 metric tons (140,660 lbm) to low Earth orbit (LEO) and 58,860 lbm to geosynchronous orbit (GEO). The Falcon Heavy is comprised of a center core and two side core boosters, each with nine Merlin engines, totaling 27 Merlin rocket engines that produce roughly five million pounds of thrust at liftoff.
“The whole concept of reuse which SpaceX has matured in a tremendous way – you don’t want to throw away rockets that can be used again if you don’t have to,” Lauderdale noted.
In order to reuse the rocket boosters, they have to have enough fuel to bring them back in a safe and controlled manner, Lauderdale said. Landing on the ground is one thing, but SpaceX also has landed boosters on drone ships in the ocean, where the water is constantly moving.
“If you have a drone ship, you have to worry about how bumpy the ocean is – that could make recovery more hazardous for the rocket coming back,” Lauderdale said. “The waves are going up and down, the ship is going up and down six and seven feet – that’s going to affect the ability to make a safe landing.”
GEO orbits also can be more difficult to obtain than LEO, Lauderdale noted. More propulsion is needed to reach GEO, which is about 22,000 miles above Earth. In order to be in a particular orbit, an object also must be traveling at a certain speed – either from the rocket itself, or the satellite’s own propulsion mechanisms.
Often, satellites will be deposited in a transfer orbit, at the perigee – the point closest to Earth – and finish the ellipse to the apogee, or point farthest from the Earth, Lauderdale said. If the rocket does the work, more of the satellite’s mass can be dedicated to its capabilities; if a transfer orbit is used, it may mean a cheaper rocket ride, but then part of the satellite’s mass is going to be dedicated to propulsion.
USSF-44 included six payloads on one satellite that advance communications, space weather sensing, and other technologies into near-geosynchronous orbits.
Managing multiple payloads isn’t just a matter of weight and size. Some payloads need to be kept at certain temperatures, others need power or fuel. To accomplish this, USSF-44 used the
Long Duration Propulsive EELV (Evolved Expendable Launch Vehicle) Secondary Payload Adapter (ESPA). The LDPE-2 is a spacecraft built around the ESPAStar Bus, developed by Northrop Grumman, and provides added propulsion, power, and avionics subsystems enabling operations as a fully functional satellite, said Lt. Col. Michael Rupp, materiel leader for the LDPE and Rooster programs at SSC.
"ESPAStar vehicles can use excess payload space on launches and our streamlined integration process allows for unification at the launch site," said Troy Brashear, vice president, national security systems, Northrop Grumman. "These capabilities enhance mission value and redefine rapid access to space as we provide the U.S. Space Force with the technology to make their missions more efficient."
The six payloads included three separable and three hosted payloads on LDPE-2. The separable payloads – which will fly independently – included Alpine, a Millennium Space Systems program to demonstrate GEO small satellite designs and leverage commercial GEO communications; Linus, a Lockheed Martin Independent Research and Development GEO servicing risk reduction effort; and Tetra-1, an SSC prototype small satellite designed as a pathfinder for streamlined acquisition processes, innovative methods of space vehicle design and on-orbit Tactics Techniques and Procedures development.
The hosted payloads - which stay attached to the LDPE-2 in orbit - include: Mustang, a small size/weight/power communications experiment; Xenon, a commercial off-the-shelf component maturation for flight at GEO; and Energetic Charged Particle-Lite, an SSC space weather sensor.
“A lot of this is tech demonstration to make sure that we can get the capabilities to meet the coming challenges later in the decade,” Lauderdale said.
“We’re working with these multiple payloads, making sure they don’t cause any harm to each other, working through the integration issues and staying on the schedule so that we can safely deliver every one of them to their orbits and bring this new capability to the warfighter,” Lauderdale said.
“Our space capabilities are supporting our terrestrial forces in accomplishing our nation’s objectives,” Lauderdale said. “That’s a key role. One of the things we see is an asymmetric threat from our near peers – they are going to look to attack some of our strengths and try to interfere with the capabilities we can deliver from and through space to the warfighter.”
“We are looking for how we can rapidly reconstitute and deliver capabilities,” in the event some space assets are damaged or destroyed, Lauderdale said. “These kinds of multi-manifested missions, where you have all these disparate payloads, they provide us the ability to deliver multiple things into different places. It’s part of a layered strategy for getting mission capability on orbit.”
LDPE-2 has now completed its month-long post-launch checkout phase, and is in the process of deploying the three separable payloads into their respective orbits, Rupp said. LDPE-2, with the remaining three payloads on board, will be in GEO orbit for a one-year mission life, with the space vehicle being operated from the Research, Development, Test, and Evaluation Support Complex at Kirtland AFB, New Mexico.
“LDPE has propulsion so it can move these satellites around in orbit and place them exactly where they want to be,” Rupp said. “It’s a coordinated effort between SSC and the mission partners as to when they want to be deployed and where they need to be to maximize their testing and prototyping.”
This is the second launch to use the LDPE satellite, Rupp noted. The first was the STP-3 launch in late 2021, the second was USSF-44, and the third will be USSF-67 in January 2023.
“We’re launching two satellites within 70 days of one another, which is fantastic from a program perspective,” Rupp said.
“The real benefit of the LDPE program is to essentially provide a ride for these smaller payloads,” Rupp said. “The mission partners are able to cheaply and rapidly test out and prototype these capabilities and insert them into future programs without having to spend a lot of time and resources doing it themselves. It enables that technology insertion to get after the fight now.”
“We had a great launch and we’re really happy with the partnership between SSC Launch Enterprise and SpaceX – our work started then, but it didn’t end there,” Rupp said. “We’re looking forward to our year of mission life and to future success.”