Bengaluru Startup Othisis Hot-Fires a 3D-Printed Cryogenic Rocket Engine

A small team, a big hot-fire

Bengaluru-based Othisis Systems has hot-fired a fully 3D-printed cryogenic rocket engine, marking a significant milestone for the young Indian startup. The 5 kN engine runs on liquid oxygen and methane, uses regenerative cooling, and is intended to power the company's reusable VTVL rocket.

The engine by the numbers

The engine produced 5 kN of thrust at a chamber pressure of 35 bar, with a total impulse of 100 kN seconds. Those are modest figures by heavy-lift standards, but they are enough for a small- to medium-satellite launch vehicle or a reusable hopper test stage. The entire engine was 3D printed, which let the team integrate complex cooling channels directly into the chamber walls rather than building them from separate parts.

Regenerative cooling and a modular pintle injector

Regenerative cooling is what makes a long burn possible. Propellant flows through channels around the combustion chamber before entering the injector, absorbing heat that would otherwise cook the walls. Othisis also used a modular pintle injector design, which means the same basic engine can be scaled to different thrust levels by swapping one component.

Failure before success

The test did not come easily. The team ran more than 20 test cycles and faced three failed ignition attempts before achieving a sustained burn. They built the propellant feed system, sourced cryogenic-rated valves after several component failures, and developed their own control and data acquisition electronics. Founder Syed Affan, who started the company in 2023 while still an undergraduate, grew Othisis out of a rocketry Discord community.

Why this matters for India's space sector

India's private space industry is moving fast, and startups like Othisis are showing that small teams can now iterate on rocket hardware quickly thanks to additive manufacturing. 3D printing cuts lead times, reduces part count, and makes complex internal geometry practical. For a young company with limited funding, that is a huge advantage over traditional machining and brazed assemblies.

What happens next

Othisis says the engine will fly on a reusable hopper vehicle planned for later this year. If that demo succeeds, the company will have proven not just that its engine works, but that a lean Indian startup can design, build, and test cryogenic propulsion in-house. That would put it in a small but growing club of private firms worldwide aiming at reusable small launch.