ABL Space Systems to debut its RS1 rocket as soon as January

An RS1 first stage at ABL’s headquarters in El Segundo, California. Note the nine radial mounting points for its engines. Credit: ABL Space Systems

DEC. 17, 2021—FCC filings by ABL Space Systems have revealed that the company is planning to launch the first flight of its RS1 launch vehicle as soon as January 31, 2022. The mission, which is being called Demo-1, will launch two 6U CubeSat payloads for OMNITEQ (formerly L2 Aerospace) from Launch Complex 3C at the Pacific Spaceport Complex – Alaska.

RS1 is a 27-meter-tall, two-stage rocket that has been in development by ABL since the company’s inception in 2017. The rocket uses a familiar engine configuration, with nine E2 gas-generator cycle engines on its first stage and a single vacuum-optimized E2 on its second stage, all burning RP-1 and liquid oxygen. Unusually, however, RS1 is also capable of running on Jet-A aviation fuel, and its first stage engines are mounted in a circle with no center engine.

The rocket is supported by ABL’s end-to-end ground system solution, named GS0. The system, like RS1 itself, is fully containerized with the aim of getting as close to a “pad-in-the-box” solution as possible. It supports RP-1 and Jet-A as well as cryogenic propellants such as methane and liquid hydrogen, with the goal of supporting not just RS1, but any small launch vehicle or payload that may use other propellants. The combined RS1-GS0 architecture is designed to be highly responsive for “launch-on-need” requirements, with ABL claiming launch readiness in just an hour “for a pre-planned mission employing pre-integrated payloads.”

The upcoming Demo-1 mission aims to demonstrate the full capability of the RS1 launch vehicle. This includes an initial orbit insertion into a 200 x 350 km orbit at an inclination of 87°, where RS1 will release the two 6U satellites flying onboard. However, unlike most test flights, the Demo-1 mission will also include a second ignition for RS1’s second stage, burning at apogee to circularize its orbit to a continuous 350 km altitude.

An RS1 first stage is raised to vertical at ABL’s Mojave test site. Credit: ABL Space Systems

Demo-1, in a manner reminiscent of Astra’s first flight attempts, will fly from the Pacific Spaceport Complex on Kodiak Island, AK. RS1 will lift off from launchpad 3C, flying a nearly due-south trajectory. Based on standard RS1 launch timelines, the Demo-1 rocket will likely be integrated just over a week before launch. With roll-out occurring two days before, the rocket will be raised to its vertical position just one day before launch. However, due to the nature of the mission, these timelines are likely to be extended more than normal. It is not yet clear whether the two OMNITEQ CubeSats on Demo-1 will be loaded like traditional payloads or in RS1’s integrated CubeSat bay, which has doors isolated from the rest of the fairing allowing late-loading of CubeSats up to five days before launch.

RS1’s reference launch profile. Credit: ABL Space Systems

On launch day, ABL uses a “load-and-go” style launch operation, similar to that of Falcon 9. Propellant loading starts at 20 minutes and 30 seconds before liftoff, with loading terminated and the terminal count starting at 5 minutes before liftoff. During a nominal launch, RS1’s first stage burns for just under three minutes, separating at 98 kilometers in altitude and at a velocity of 3.1 km/s. The second stage burns for another five minutes, cutting off at T+ 7:59 at a velocity of about 7.8 km/s.

An artist’s rendering of RS1 carrying NASA’s Cryogenic Demonstration Mission to orbit. The mission is planned to launch in 2023. Credit: Lavie Ohana/Space Scout

The imminent Demo-1 mission marks a major milestone for ABL, a company that while largely shrouded in secrecy, has gained an increasingly stunning launch manifest with at least 78 launches on contract for the yet-to-fly RS1 launch vehicle. Lockheed Martin has been the largest buyer of RS1 missions, purchasing 26 launches with options for an extra 32 through 2029, for a total of 58 launches. Other high-profile payloads flying RS1 include NASA’s Cryogenic Demonstration Mission, two test satellites for Amazon’s Project Kuiper mega-constellation, and the UK Pathfinder mission.

Importantly, ABL will leverage special capabilities unique to its launch systems for two of these missions. NASA’s Cryogenic Demonstration Mission requires liquid hydrogen support for its payload, a capability few launch vehicles or launchpads offer. ABL stated that it would “extend [GS0 functionality] to meet NASA’s mission need for LH2 operations,” as well as also further advancing RS1 “with a hydrogen-compatible fairing and payload support systems,” enabling compatibility with future cryogenic payloads.

Where the cryo-demo mission relies on the adaptability of the RS1 system, the UK Pathfinder and all future RS1 launches from the UK will rely on the system’s deployability. The mission, which is currently aiming to be the first orbital launch from the British Isles, will launch from the Shetland Space Centre. The space center, located on the northernmost island of the UK, is far from much of the permanent infrastructure most launch sites offer. Lockheed Martin, prime contractor for both the Pathfinder and cryo-demo mission, stated that the “flexible, integrated GS0 launch system and RS1 rocket allows for a rapid and cost-effective deployment with outstanding launch performance.”

“The technology required to launch small satellites to orbit quickly and at a low cost has existed for decades. Despite this, the launch vehicle industry has continued to pursue eye-catching but unnecessarily complex architectures.”
— ABL Space Systems, 2018

These exceptional capabilities come at what may be perceived as a severe cost in today’s launch market—RS1 is fully expendable with zero plans for reuse. However, ABL wears RS1’s expendability with pride, stating that the rocket features “no over-design, no gimmicks, just reliable, regular launches.” The company even boldly stated in 2018 that “the technology required to launch [small satellites] to orbit quickly and at a low cost has existed for decades. Despite this, the launch vehicle industry has continued to pursue eye-catching but unnecessarily complex architectures.”

Three years later, it would appear the company’s slogan—“Launch Simply”—has certainly resonated with investors and customers alike. The rocket’s launch manifest is currently equal to nearly one-half that of the retired Delta II’s entire flight history, and the company continues to raise hundreds of millions, placing it at a $1.3 billion valuation back in March of this year. Despite ABL’s impressive progress, the company still remains quiet on the public front, with not much more to show other than its website and occasional press releases. With the upcoming Demo-1 mission, already much-anticipated by a significant part of the industry, ABL and its rocket are set to enter the spotlight and take much of the spaceflight community by surprise.

Article by Lavie Ohana (@lavie154). Derek Newsome (@derekdotspace) contributed to the contents of this article. Edited by David D. and An Tran.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.