Launcher’s 3D printed E-2 liquid rocket engine reaches full thrust

The launch vehicle’s 3D-printed E-2 liquid rocket engine successfully demonstrated rated thrust, pressure, and oxidizer/fuel mixture ratio for the first time in a test fire at NASA’s Stennis Space Center .

E-2 is a closed-cycle, 3D-printed, high-performance liquid rocket engine under development for the Launcher Light launch vehicle (scheduled maiden launch in 2024). A single E-2 engine will propel Launcher Light into low Earth orbit with 150 kg payload.

Data from the E-2 engine test fire reads: 10 metric tons of thrust (22,046 lbf), 100 bar (1,450 psi) of combustion pressure and the best performing propellant mixture ratio 2.62 for LOX/kerosene at 100 bar pressure.

The E-2’s chamber is uniquely liquid oxygen cooled and 3D printed in one piece copper alloy. It also uses a copper-chromium-zirconium (CuCrZr) alloy for the industrial supply chain, which reduces supply chain costs and stresses compared to the aerospace-grade copper alloy typically used in 3D printed combustion chambers.

Launcher is the first small launch company to use 3D printed copper alloy, and is a leader in small launch 3D printing technology with the development of the first large format (100 x 45 x 45 cm) custom 3D printer in partnership with AMCM. The launcher’s one-piece copper-alloy combustion chamber is produced on an AMCM M4K 3D printer. While E-2’s state-of-the-art coaxial injector is 3D printed on a Velo3D Sapphire.

These technologies enable higher performance which translates to more payload per rocket and lower prices for Launcher customers.

In a next step, Launcher will test again in early May with the same chamber and injector, slightly reworked to remove any film cooling – which increases performance. The goal is to increase C* efficiency from 90% in this test to Launcher⁠’s 98% goal.

E-2 is a closed cycle engine and the development of its high pressure (310 bar) high efficiency single shaft turbopump is progressing in parallel. In March 2022, Launcher successfully tested E-2’s liquid oxygen turbine and pump in boost mode at 130% rated flow. The launch vehicle plans to demonstrate a three-minute, full-duration test with the E-2 integrated turbopump in a closed-cycle configuration in the fourth quarter of 2022.