WASHINGTON — A Cygnus cargo spacecraft is scheduled to launch on a Falcon 9 rocket for the first time, a combination that requires more changes to the rocket than the spacecraft.
NASA announced in a press conference on January 26 that it is targeting January 30 at 12:07 PM ET to launch the NG-20 cargo mission from Space Launch Complex 40 at Cape Canaveral. This represents a one-day delay from previous plans, which the agency said “accommodates launch pad readiness.” If Cygnus launches on that day, it will arrive at the ISS as early as February 1.
This launch marks the first time that Northrop Grumman's Cygnus cargo spacecraft has flown aboard a Falcon 9. All previous Cygnus launches have been on Northrop's Antares launch vehicle except for two missions that were launched on United Launch Alliance's Atlas 5 after a launch failure Antares in 2014.
Northrop plans to launch at least three Cygnus missions on Falcon 9 rockets, and is working with Firefly Aerospace on a new version of the Antares, replacing the Ukrainian-made first stage powered by Russian engines with a stage developed by Firefly using its own engines. The launch of this vehicle, Antares 330, is scheduled to begin in mid-2025.
The transition to the Falcon 9 has been relatively smooth for Northrop. “We didn't really have to make any modifications to the Cygnus,” Cyrus Dalla, vice president and general manager of Tactical Space Systems at Northrop Grumman, said during the press conference. The company has made minor changes to its cargo loading process, which it attributes to doing so in a new facility with different equipment.
He added that the shift in launch vehicles does not change Cygnus' capabilities. The NG-20 mission will carry just over 3,700 kilograms of cargo, which is the capacity of the current version of the vehicle.
However, SpaceX had to make changes to accommodate Cygnus, specifically its ability to “delay load” cargo within 24 hours of launch. Antares has a “pop-up” hatch at the top of the rocket's payload fascia, allowing access to the Cygnus inside for loading cargo after the spacecraft is packed.
To provide delayed loading capability similar to Falcon 9 launches for Cygnus, SpaceX created what Bill Gerstenmaier, SpaceX's vice president of construction and flight reliability, called a “giga door” in the Falcon 9's fairing. It's a 1.5 x 1.2 door. meters in the side of the fairing that can be opened to provide environmentally controlled access to the Cygnus inside.
“This will be the first time we've done this,” he said, as SpaceX's Dragon spacecraft launches without a fairing. “It took a lot of modifications on our part to get this device ready to fly.” He added that placing the door at the payload interface does not affect SpaceX's ability to recover and reuse it.
“We really appreciate how SpaceX has worked with us to accommodate cargo flow and integration, and we've been able to reuse a lot of our procedures,” Dalla said.
Along with developing the payload door for Cygnus launches, SpaceX has been testing modifications to its carrier erector at Launch Complex 39A, enabling it to load liquid methane and oxygen fuel. This is required for the upcoming launch of the IM-1 lunar lander by Intuitive Machines, which will be fueled on the pad, inside the payload interface, shortly before launch.
SpaceX has been testing this equipment to ensure it is ready for the launch of IM-1, which is currently expected to launch in mid-February, Gerstenmaier said. “This work is very much on the right track,” he added. “It's an interesting integration, but as you can see, even with this Northrop Grumman 20 mission, we at SpaceX like to do innovative and innovative things.”