New Frontier Aerospace Successfully Tests Its 3D Printed Mjölnir Rocket Engine

Mjölnir refers to the hammer of the thunder god, Thor, in Norse mythology. The hammer is used as both a devastating weapon and as an instrument to deliver blessings. The Washington-based startup New Frontier Aerospace (NFA) gave its 3D printed rocket engine the same name, giving the tool a powerful impression. Now, the Mjölnir rocket engine is making headlines since its series of successful hot fire tests, advancing the technology for defense, aerospace and commercial applications.

According to NFA, the Mjölnir is the world’s most advanced compact pump-fed rocket engine. With a full-flow staged combustion cycle, Mjölnir is ideal for high-performance reusable rockets, hypersonic vehicles and orbital transfer spacecraft. The engine was also designed with sustainability in mind. It is powered by clean liquid natural gas (LNG) and is net carbon negative when sourced from bio-waste, highlighting NFA’s commitment to environmental responsibility. The engine is reusable as well, with deep throttling (which refers to the ability of a rocket engine to significantly reduce its thrust output) and easy start and stop. Mjölnir is now available as a standalone product, offering customers a propulsion solution for their missions.

The 3D printed Mjölnir rocket engine (left) and NFA’s Intercontinental Rocket Liner (right)

This engine’s development was made possible through seed funding from National Security Innovation Capital, part of the Defense Innovation Unit, with this sustained engine test series funded by NASA. The consistent results from these hot fire tests mark a significant step forward for NFA as it continues to redefine aerospace propulsion. Bill Bruner, CEO of NFA, exclaimed his enthusiasm: “We are proud of the amazing team that built this program and thrilled with the engine’s performance during this series of hot fire tests. Mjölnir’s compact design, unmatched efficiency, and clean fuel make it a game-changer for hypersonic flight and space propulsion. It is poised to power our ambitious roadmap and open new possibilities for our customers.”