Contractors want America’s “moon rocket” to be more than that
By Cat Hofacker|August 26, 2021
Reporting from the Space Symposium
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COLORADO SPRINGS, Colo. — When the first Space Launch System rocket blasts off from Florida with an unoccupied Orion capsule, possibly by the end of the year, a successful loop around the moon could prove to be a win for more than the U.S. politicians and space enthusiasts who have stood by the SLS program through delays and cost overruns in the name of seeing Americans return to the moon in 2024.
The win could help the SLS contractors make their case that the emerging fleet of huge, government-owned expendable rockets can do more than launch astronauts for NASA. They envision SLS rockets boosting robotic probes and fantastic new astronomy telescopes for NASA, and spy satellites and military spacecraft for the Pentagon and intelligence community.
“This is a national asset for a national agenda,” said Jim Maser, who leads the space business unit at Aerojet Rocketdyne that builds the RS-25 engines that will propel the SLS core stages built by Boeing.
Maser was among the executives who spoke during a Wednesday media roundtable discussion with reporters here at the Space Symposium.
The executives touted the flexibility of a planned larger variant of the SLS rockets, the Block 1B, each with the same core as the Block 1 design but with a more powerful upper stage.
A single SLS equipped with this Exploration Upper Stage and its four Aerojet Rocketdyne RL-10 engines could propel an Orion capsule plus a cargo spacecraft toward the moon, or it could boost multiple spacecraft enclosed in a fairing toward the outer solar system without requiring gravity assists.
With a diameter of 8.4 meters, the fairing would be ideal for launching large robotic probes beyond the moon to destinations such as Jupiter’s moons, or whatever space telescopes NASA pursues after the James Webb, said David Burks, director of sales and marketing for Boeing’s deep space programs.
Fairing size is a big limitation for today’s telescopes, including Webb, whose 6.5-meter-diameter primary mirror had to be designed to fold up inside the 5-meter-diameter fairing of its Ariane 5 launch vehicle.
Burks said the Pentagon and U.S. intelligence agencies have also expressed interest in launching payloads on SLS.
“The point is that SLS is not just NASA’s rocket; it’s America’s rocket,” he said. “It’s a strategic asset that can be used for many other purposes.”
One limiting factor on these grand plans is the current SLS production rate. NASA has contracted Boeing and the other SLS contractors for a combination of eight Block 1s and Block 1Bs through 2030. That amounts to one SLS per year starting in 2023 with the Artemis-2 mission, the flight of an Orion and four astronauts around the moon and home. Additionally, Boeing and the other SLS contractors ran into a series of delays building the first SLS rocket, the one for Artemis-1, the inaugural SLS launch with the unoccupied Orion capsule around the moon. That mission was supposed to happen in 2017, but Boeing in the past has largely attributed the slipping launch date to challenges associated with first-time production.
Burks said production of the second, third and fourth SLS core stages is “going so much more smoothly,” and Boeing could increase production to two core stages per year if contracted by NASA or another agency for additional missions.
Each core’s RS-25 engines are among the SLS components that take the longest to produce, Aerojet’s Maser said. The company is refurbishing previously flown RS-25s from the space shuttle orbiters for the first four Artemis flights, and in parallel has begun producing more engines at its Los Angeles factory.
Aerojet’s production capacity could support two SLS launches per year “in the Artemis-4 timeframe” of 2025, Maser said, “but we just have to get it going.”
Before an SLS can launch anything to deep space, the first rocket must blast the unoccupied Orion capsule on its way around the moon “within this calendar year,” said Lorna Kenna of Jacobs.
At the briefing Kenna provided an update on the company’s progress in stacking the Artemis-1 hardware in the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida.
In late September, technicians are scheduled to roll the Orion capsule over to the VAB where the rocket is waiting and begin joining the two vehicles for final tests. Those include wet dress rehearsals in which the core stage’s propellant tanks will be filled with liquid hydrogen and liquid oxygen as if in preparation for a launch, but the engines won’t be fired.