Relativity Space

Draft

Founded in 2015 on a specific and unusual thesis: that additive manufacturing would fundamentally change how launch vehicles are built. The company is worth recording as a clear test of that proposition.

Founded: 2015
Thesis: Large-scale metal additive manufacturing as the primary source of competitive advantage
First vehicle: Terran 1, small launcher, flown once in 2023
Current vehicle: Terran R, medium-lift and reusable, in development

The additive manufacturing thesis

The argument was that printing large structures rather than machining, welding and assembling them would reduce part count, shorten the design iteration cycle, and lower the capital cost of a factory.

Claimed benefit	Assessment
Fewer parts	Real. A printed component can replace an assembly of many machined parts and their fasteners
Faster iteration	Real for components. A design change becomes a file change rather than retooling
Lower factory capital	Partly. Printers replace some tooling, and other production equipment is still required
Lower unit cost	Not established. Printing is slow, and print time scales with part volume
Better performance	No. Printed metal is generally not superior to wrought material

The honest summary is that additive manufacturing is genuinely valuable for complex components, particularly engine parts with internal cooling passages that cannot be machined at all, and that its advantage diminishes for large simple structures such as tanks, where conventional forming and welding is fast and well understood.

This distinction matters because engine components are exactly where the industry has adopted printing broadly. Nearly every modern engine programme uses printed injectors, manifolds and chamber components. The contested claim was never that printing helps, but that printing the whole vehicle is advantageous.

Terran 1

A small launcher, roughly 1.25 t to LEO, flown once in March 2023.

The flight reached stage separation and the second stage failed to reach orbit. For a first flight of a new vehicle this is an ordinary outcome, and it demonstrated the substantial point: a largely printed structure survived launch loads and the ascent environment.

The company then retired Terran 1 after that single flight and redirected entirely to Terran R.

That decision is the most informative thing about the company. It is a direct recognition of the market structure described in Rocket Lab and in The launch market: the small dedicated launch segment is compressed by rideshare, and a small vehicle is not a viable standalone business regardless of how it is manufactured.

Terran R

A medium-lift vehicle targeting the constellation deployment segment, with a reusable first stage and methalox propulsion.

The additive manufacturing content is reduced relative to the original thesis. Printing is applied where it is advantageous, principally engines and complex components, and conventional methods are used where they are faster, notably large tank structures.

That evolution is the thesis being tested and partially revised in public, which is more instructive than either its original form or its abandonment would have been.

What the case illustrates

Several general points follow, and they apply beyond this company.

A manufacturing method is rarely a durable advantage. If printing large structures were decisively cheaper, competitors would adopt it, and several have adopted it for the components where it helps. Advantage in launch has come from architecture and cadence rather than from a process innovation. See Launch and mission economics.

Market segment matters more than vehicle quality. A well-executed small launcher entering a compressed segment is in a worse position than a mediocre vehicle in a growing one. Terran 1’s retirement after one flight reflects that directly.

Public thesis revision is a good sign, not a bad one. A company that narrows an ambitious claim to the cases where it holds is behaving correctly, even though the narrowing is often reported as a retreat.

Capital intensity remains the binding constraint. Developing a medium-lift reusable vehicle requires funding on a scale that few private companies can raise, which is the structural problem described in Startups and venture capital.

Status

Terran R remains in development and has not flown. The company’s ultimate assessment therefore depends on an outcome that has not occurred, and this page should be revised when it does.

References

Relativity Space published technical material and payload user guides.
FAA Office of Commercial Space Transportation licensing records for the Terran 1 flight.
Blakey-Milner, B. et al. “Metal additive manufacturing in aerospace: A review”, Materials and Design, 209:110008, 2021.
Gradl, P. R. et al. “Additive Manufacturing of Liquid Rocket Engine Combustion Devices”, AIAA 2019-4362, on where printing genuinely helps.