Chennai-Based Agnikul Cosmos Unveils World’s Largest Single-Piece 3D-Printed Rocket Engine

In a groundbreaking achievement for India’s private space sector, Chennai-based Agnikul Cosmos has successfully developed the world’s largest single-piece 3D-printed rocket engine, known as Agnilet. The milestone marks a significant advancement in rocket propulsion technology and reaffirms India’s growing presence in the global space industry.

Agnilet is fabricated entirely from a single piece of metal using advanced 3D printing techniques with no assembled parts. This not only simplifies the engine’s construction but also dramatically reduces the chances of leaks or mechanical failures. The engine is made from Inconel, a high-performance nickel-chromium-based superalloy capable of withstanding extreme pressure and temperature conditions typical of rocket launches.

The innovation reflects Agnikul’s vision of affordable and on-demand access to space, especially for small satellite missions. The Agnilet engine is designed for Agnibaan, Agnikul’s customizable small satellite launch vehicle (SSLV), which is capable of lifting payloads up to 100 kg into low Earth orbit (LEO). The vehicle is modular and mobile, designed to launch from India’s first private launchpad, also established by Agnikul at the Satish Dhawan Space Centre (SDSC), Sriharikota.

What sets this achievement apart on the global stage is the scale and complexity of the single-piece engine. While several aerospace companies have adopted 3D printing for parts of engines, creating an entire engine — including combustion chamber, injectors, and cooling channels — as a single unit is rare and difficult due to the precision and material strength required.

Agnikul Cosmos has already conducted multiple hot-fire tests of the Agnilet engine, with successful results. These tests validate both the performance and durability of the engine under real-world conditions.

This development is also symbolic of India’s thriving private aerospace sector, following the Indian government's move to open the space sector to private players under IN-SPACe. Agnikul, incubated at IIT Madras, has received strong backing from both public and private entities and continues to pioneer innovations in space launch technologies.

As the space race becomes increasingly competitive, Agnikul Cosmos’s 3D-printed Agnilet engine stands out as a technological marvel, offering a blend of efficiency, reliability, and cost-effectiveness — crucial factors in the new era of space exploration and commercialization.