Relativity Space Is Printing Terran R Dome Sections
Not long after Terran 1 lifted off with an impressive first and only flight, Relativity announced a few plan changes relating to Terran R. This partially reusable 3D printed rocket will prioritize saving the first stage and is trying to launch in 2026. In order to create such an ambitious launch vehicle, Relativity recently started revamping and creating massive test and production sites specifically for this rocket.
This comes in addition to physical progress on the main Aeon R engines and even large test domes. Recent updates suggest the company is trying to find a way to print the strongest domes possible while keeping them lightweight. An important feature for the booster in particular which will need fuel reserves to land after it launches.
By now, Relativity’s new factory and 3D printers are busy trying different designs and print techniques for Terran R. Over the next few months this work will determine the capability of this next generation launch system. Here I will go more in-depth into the recent progress Relativity has made, whether or not they are on track for Terran R’s first launch, a general design overview, and more.
Structure Progress
Well before the launch of Terran 1, Relativity was planning on making a much larger and more ambitious launch vehicle. They had even test-printed Terran R sections using a vertical 3D printer, the same system used for Terran 1’s main sections. Since then, however, a lot has changed, and in order to compensate for the much larger prints needed, among other changes, horizontal printing is now being used.
In terms of progress, a few days ago on the 8th, Relativity tweeted saying, “Fresh off the printer. Our newest 18ft demonstration dome features added “ribs,” designed to increase stiffness and prevent buckling as the dome is made thinner optimizing on mass.” This included an image of the two domes where you can clearly see the ribs as mentioned in the tweet. As a two-stage, 270-foot-tall rocket with an 18-foot diameter and a 5-meter payload fairing, Terran R is much larger than anything Relativity has made in the past.
The company’s newest generation of 3D printers removes ceiling height constraints. Through horizontal printing, these printers are capable of printing objects up to 120 feet long and 24 feet wide, resulting in an increased volume capacity of 55x its 3rd generation predecessor. In addition, in a statement the company said, “Most immediately, Terran R will be the first product in a series of products to benefit from use of lighter materials and a faster production time, creating significant cost reductions for customers downstream.”
It’s very clear from all these examples that the current hurdle is getting the strength-to-weight ratio perfect. During an actual launch, shortly after stage separation, the first stage of Terran R will perform a slow flip maneuver using its cold gas Reaction Control System (RCS). Grid fins deploy, followed by igniting engines to complete entry burns, slowing velocity and reducing peak loads and heating. The various vehicle aerosurfaces and strakes are designed to enable a high angle of attack on entry. This reduces the payload penalty for reuse with less propellent used on entry burns. Additionally, unique aerodynamic features are meant to result in a more stable entry profile with controlled flow separation around the vehicle.
Terran R is designed for atmospheric entry with grid fin control. The vehicle will then ignite engines for a landing burn and command the leg slider mechanism to open, which will then passively deploy with the aid of aerodynamics. The first stage will then touchdown on a downrange ship in the ocean. Once the first stage has completed its reentry, it will go for inspection, refurbishment, and recertification for its next flight from Cape Canaveral. This process is extremely precise and needs to be perfect as we’ve seen from current similar launch operations with SpaceX. The company also intends to design major parts of the vehicle for 20 reuses right away, with strategic development of reusability criteria and rapid learning from flight data to continuously improve through successive vehicle block upgrades.
Infrastructure
Relativity knows that Terran R requires much more than just a design, but an immense amount of infrastructure for practically every part. Between the new 3D printers, factories, engine test stands, etc. the company has been focusing on the backbone of this rocket.
As of right now, Terran R’s production homebase is in Long Beach, CA at Relativity’s one million square foot headquarters, home to its set of brand new pritners. At production run rate from this single factory, the company estimates its ability to initially produce and fly more than 45 Terran R’s annually, with adaptive software-driven production infrastructure able to build more or less first or second stage components based on reuse rate and customer demand over time.
Stage and engine testing for Terran R will take place at Relativity’s test facilities, located at NASA Stennis Space Center in Mississippi. Not to mention, announced in October 2022, Relativity is actively building out additional new test stands and infrastructure on a more than 150-acre expansion to support a high volume of Terran R testing as vehicle production and launch cadence increases. The completion of a new dual-bay vertical engine test stand is expected by Fall 2023, in addition to the multiple test areas at each of Relativity’s E2 and E4 sites repurposed from Terran 1 development. A few weeks ago the company released a new video of the construction at this site which shows decent progress. They likely are on track to finish it within the next couple of months as planned.
Once Terran R and its first test articles are finally complete, they need a safe site to launch it. Leveraging Space Launch Complex 16, Relativity’s current orbital launch site at Space Force Base in Cape Canaveral, FL, the company plans to build a secondary launch pad adjacent to its existing Terran 1 test and launch facilities. After completion of production and initial structural proto-qualification testing in Long Beach, Terran R vehicles will travel by sea through the Panama Canal to Mississippi for testing and then Florida for launch. Reused boosters will stay in Florida and be rapidly refurbished for additional launches.
While there is a lot on the company’s plate, the funding has been quite significant. Relativity currently has Launch Service Agreements (LSA’s) that amount to more than $1.65 billion across seven customers. Relativity points out that “With satellite technology advancements, demand for bandwidth soaring, and satellite constellations representing the largest part of the growing launch market with a Total Addressable Market of over $30B/year by 2030, Terran R was developed to accommodate the growing demand for large constellation launch services.” They believe this rocket could provide some competition to industry leaders such as the Falcon 9.
Comparing the two, Terran R is expected to have a LEO payload capacity of around 23,500kg. The Falcon 9 on the other hand features a very similar capacity of 22,800kg. More important, however, is cost. If companies want to compete with SpaceX and get consistent launch contracts, they need to offer a more affordable service. This obviously is hard to do with Falcon 9 reuse so developed. A Falcon 9 usually costs around $67 million per launch. A few months ago it was reported that Terran R will be priced around $55 million per launch. While cheaper, there are a lot of unknowns and work left before this rocket is up and running. This being said, at that price, it would most definitely be very competitive if reliable.
They describe Terran R as a customer-centric next generation launch vehicle designed to meet the needs of commercial companies and government entities sending payloads into LEO, MEO, GEO, and beyond. Terran R’s architecture choices are meant to enable accelerated development and the ability to deliver a rapidly scaling launch cadence for customers. When in a reusable configuration, Terran R should be capable of launching 23,500kg to Low Earth Orbit (LEO) or 5,500kg to a Geosynchronous Transfer Orbit (GTO), both with downrange landing, or up to a maximum payload of 33,500kg to LEO in expendable configuration. Horizontal integration to the vehicle will be supported through a standard Payload Attach Fitting (PAF) interface, with payload integration configurations available for clusters of constellation satellites, single large satellites, or other unique spacecraft. If everything goes according to plan, starting in 2026, Terran R will launch from Space Launch Complex 16, the company’s orbital launch site at Cape Canaveral, Florida.
Terran R’s first stage will be outfitted with 13 3D-printed gas generator cycle Aeon R LOx/Methane rocket engines each capable of 258,000 lb. sea level thrust, while its second stage houses a single LOx/Methane Aeon Vac engine with 279,000 lb. vacuum thrust. These engines benefit from Relativity’s advanced experience developing gas generator engines and vehicle stages with the oxygen/methane propellant combination.
Conclusion
Relativity Space is continuing to work toward the first launch of Terran R. Before they can print massive full rocket segments, however, they need to complete all the different infrastructure projects. This includes engine stands, factories, and much more. We will have to wait and see how it progresses and the impact it has on the space industry.