Rocket engines are tough pieces of hardware to build, but it's possible that 3D printing them could be the next big thing. Relativity certainly thinks so, and has raised about a billion dollars — now Launcher is ready to accept your money too, after demonstrating full thrust on its 3D-printed E-2 engine.
Though they're still a ways off from getting to orbit, a successful test like this is a huge step toward a working launch vehicle. The Launcher Light will be small and very efficient, aiming for a low cost to orbit and quick turnaround. But of course first it needs working engines.
Last week saw the first full-scale thrust test of the E-2, down at NASA's Stennis Space Center in Mississippi. The test demonstrated about 22,046 pound-feet of thrust (about 10 metric tons) using LOX/Kerosene at 100 bars of combustion pressure.
This is the thrust they've been aiming for in spec sheets and inching toward in other measures, and they reached it "without the hardware melting," said founder and CEO Max Haot. That's considered a sub-optimal condition and there's plenty of opportunity for that to happen in these tests. But it ran for four 10-second stretches and was still in "perfect condition" after, showing off its potential for reusability.
The combustion chamber is fully 3D-printed in copper alloy rather than milled or cast like traditional ones. Things have come a long way since the MakerBot; Launcher works with AMCM to fabricate the piece on an M4K printer, and the injector was made on a Velo3D Sapphire.
This is only one milestone among many to come for the engine; a turbopump with the necessary 3x pressure of the nominal combustion pressure is being tested in parallel. They'll be integrated after being individually tested, and the resulting integrated engine will then begin its own proving phase.
As for reusability, Launcher Light will be expendable (if cheap) — "But we have plans to scale to a nine-engine version which will have a reusable first stage," Haot said. "The first step though is to prove we can deliver 150 kg of payload to orbit with an expendable Launcher Light."
It should be a big 2022 for Launcher: the tanks and fairing for the Light should be showable by the end of the year, possibly even a mostly assembled vehicle. And the company's other big project, Orbiter, will be headed to space for on-orbit testing in October aboard a Falcon 9 rideshare.
You can watch the test below: