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Relativity shelves Terran 1 after one launch, redesigns Terran R

Terran R, April 2023 version
The revised version of the Terran R features increased performance, but will only reuse the first stage. Credit: Relativity Space

WASHINGTON — Relativity Space has decided to retire its Terran 1 small launch vehicle after a single flight that failed to reach orbit, focusing its resources on a revised version of its larger Terran R rocket.

Relativity said April 12 that, less than a month after the first launch of its Terran 1 rocket, which suffered a malfunction of its upper stage engine, the company was setting that vehicle aside to work on the Terran R rocket the company announced in 2021.

“Building on momentum from Terran 1’s development and flight, Relativity is shifting its focus to design, development, and production of its next generation Terran R launch vehicle,” the company said in a series of tweets.

That launch, a test flight that carried no payload, did achieve some key test milestones, including a successful burn of the rocket’s first stage, powered by methane and liquid oxygen. The rocket’s 3D-printed structure also survived peak forces on it during ascent, called Max-Q, demonstrating that manufacturing approach was suitable for launch vehicles.

“Our first chapter as a company was to prove to the world 3D-printed rockets were viable. We just did that with Terran 1. Our second chapter is to build the next great launch company with Terran R,” Tim Ellis, chief executive of Relativity, said in a company statement.

In comments before the March 22 launch, Ellis suggested that the company might move on to the Terran R even if the Terran 1 launch failed. “Medium-heavy lift is clearly where the biggest market opportunity is for the remaining decade, with a massive launch shortage in this payload class underway,” he said then.

He said then that, in the event of a Terran 1 failure, he would ask customers if they wanted Relativity to fix those problems and fly Terran 1 again. “Or, would [they] like us to solve the remaining rocket science problems on the vehicle they are actually most interested in, Terran R?”

To address that market opportunity, Relativity announced the Terran R in 2021 at the same time it raised $650 million, its largest and most recent funding round. However, the design of that vehicle has changed in the nearly two years since that announcement.

The biggest change is a move away from full reusability. Ellis said in 2021 that it was the company’s intent to reuse all of Terran R, including its upper stage and payload fairings. “There won’t be a part that’s not reusable on the vehicle,” he said then, which he argued was possible with the use of 3D-printing technologies and “exotic” alloys.

However, the new Terran R design is a somewhat more conventional approach where only the first stage is recovered by landing on a ship downrange from the launch site, like SpaceX’s current Falcon 9 and other vehicles in development, such as Blue Origin’s New Glenn. That first stage, powered by 13 of the company’s Aeon R methane/liquid oxygen engines it is developing, is intended to be flown at least 20 times.

Relativity made no mention of reusing the upper stage, which will use a single vacuum-optimized Aeon R engine, or the vehicle’s payload fairings.

The design changes also increase payload performance. While Relativity originally said Terran R could launch more than 20,000 kilograms into low Earth orbit, the company now says that it can place 23,500 kilograms into LEO if the first stage is recovered and 33,500 kilograms if the first stage is expended. It can also insert payloads of up to 5,500 kilograms into geostationary transfer orbit while recovering the first stage.

When Relativity announced the Terran R in 2021, it planned a first launch of the vehicle in 2024, a date the company published on its web site as recently as last month. The company is now targeting 2026 for the vehicle’s first launch from Cape Canaveral’s Launch Complex 16, also used for the Terran 1 launch.

It was not clear how that delay might affect business for the rocket. The company had boasted of $1.65 billion in launch contracts but had identified few of its customers. One of those customers was OneWeb, which said last year it signed a contract for multiple Terran R launches of its second-generation satellites.

“We are thrilled to see the progress made by our friends at Relativity,” said Massimiliano Ladovaz, chief technology officer of OneWeb, in a Relativity statement. “We can’t wait to see them push on to the next evolutionary step in bringing the Terran R to market.”

The original design for the Terran R when the company announced the vehicle in June 2021. Credit: Relativity Space Credit: Relativity Space

Terran 1 investigation update

While Relativity no longer plans to launch the Terran 1, it is continuing to investigate the failure of the vehicle’s single flight.

In a statement quixotically released only as a series of images, the company said the main valves for the upper-stage Aeon Vac engine opened slower than expected. That affected the timing of propellant reaching the engine’s thrust chamber assembly and gas generator during engine startup.

The engine’s oxygen pump did not generate pressure during startup, which the company said “is consistent with a vapor bubble being present at the pump inlet.” That kept the gas generator from starting and kept the engine from reaching full power.

That investigation is ongoing. “Respecting its relationship with pertinent external parties, including the FAA, Relativity intends to deliver a comprehensive official report at the conclusion of its investigation,” the company stated. It did not offer a schedule for doing so.

Completing an investigation even after retiring a launch vehicle is not unprecedented. Astra recently concluded the investigation into its last failed Rocket 3.3 launch in June 2022, months after announcing it was scrapping that vehicle to focus on the larger Rocket 4.

It’s unclear what Relativity will do with the handful of customers it had for the Terran 1. That included NASA, which awarded the company a Venture Class Launch Services (VCLS) Demo 2 contract in December 2020 for a single Terran 1 launch. A NASA spokesperson was not able to immediately answer questions April 12 about the status of the VCLS Demo 2 award after Relativity’s announcement it would no longer fly Terran 1.

Another customer was Iridium, which had a contract for up to six Terran 1 launches of replacement satellites. However, Iridium announced a contract with SpaceX in September 2022 to launch five of those six remaining spares, leaving Relativity with at most a single launch.

Matt Desch, chief executive of Iridium, congratulated Relativity for launching Terran 1. “We applaud their transition now to completing Terran R, which is better aligned with industry’s anticipated future launch requirements,” he said in the Relativity statement.

Relativity’s Ellis was once bullish on demand for the smaller Terran 1, which was designed to place up to 1,250 kilograms into LEO. “We see almost insatiable demand for that vehicle right now,” he said in 2021 of Terran 1.

He now views Terran 1 differently. “Terran 1 was like a concept car, redefining the boundaries of what is possible by developing many valuable brand-new technologies well ahead of their time,” he said in the company statement. “Terran R is the mass-market, huge demand product that will be amazing precisely because it brings those ‘concept car’ developments into full maturity.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...