LEAP Space 3D-Prints a Full Rocket Engine for Its Bighorn Launcher

LEAP Space has unveiled the Serrano engine, the first major structural piece of its Bighorn launch vehicle. The thrust chamber was printed as a single part using large-scale direct metal laser sintering, a choice the company says directly supports its plan to manufacture rockets at an annual rate most launch companies cannot match.

Why one piece matters

Rocket engine thrust chambers are traditionally assembled from dozens of machined and welded components. That approach works, but each weld is a potential failure point, and the lead time for machined parts runs into months. By printing the chamber as a single structure, LEAP removed the assembly step entirely.

The DMLS process also lets the engineers include internal cooling channels that would be impossible to machine conventionally. Those channels keep the chamber wall from melting during the high-thrust burns the engine is designed for.

The Bighorn production goal

Serrano is a variant of LEAP's Cayenne propulsion system, a dual-mode LOX/methane architecture. The company plans to build Bighorn, its transportable orbital launcher, at more than 30 units per year on each manufacturing line. That cadence is only realistic if major components arrive at final assembly ready to bolt on, not as kits requiring weeks of machining and welding.

The Serrano announcement follows Bullfrog, LEAP's smaller reusable vehicle, completing its first flight in May 2026. The company now has two flight-proven vehicles in its lineup, and Bighorn targets a broader set of missions: orbital deployment, point-to-point logistics, contested-space operations, and defense contracts.

Additive manufacturing as production infrastructure

LEAP's pitch is that Bighorn is built with 90 percent fewer parts than conventional launch vehicles. That number only holds if the remaining parts are manufactured in ways that eliminate assembly steps. Metal 3D printing is the obvious fit for that constraint.

The next steps for Serrano are integration and testing before it flies on Bighorn. If the engine performs on the test stand as it has in simulation, LEAP will have a credible argument that serial rocket production is no longer limited by traditional supply chains.