Boom Supersonic 3D printed 193 metal parts (and counting) on the EOS M 400-4 system

As development progresses on the Symphony engine’s sprint core, Boom Supersonic reported it has produced 193 metal parts through metal additive manufacturing technology from EOS. These parts are being fabricated at EOS 3D Printing’s Austin facility using the EOS M 400‑4 machine and are crucial for subsystem testing, which includes combustor components and turbine elements. This strategic approach allows the team to validate the design and manufacturing techniques early, reducing risk before moving forward with full-scale engine builds.

Using high-performance additive manufacturing systems demonstrates how such technology can produce intricate components tailored to specific engineering requirements. Boom Supersonic engineers are currently building expertise with the EOS M 400‑4 platform, and this knowledge base is expected to support the intensification of sprint core testing. Plans are underway to relocate the 3D printer to a new testing site in Colorado this summer, enabling even more robust and iterative development.

Boom Supersonic’s engagement with 3D printing began well before the Symphony program and the ongoing work with EOS. During the development of the XB‑1 demonstrator, additive manufacturing played a pivotal role, encompassing everything from functional prototyping and tooling support to on-demand flight hardware production. That program created over 300 polymer components and 21 titanium parts using advanced machines such as Stratasys and VELO3D systems. These parts included complex engine ducts, manifolds, and louver systems—features that traditional machining could not replicate.

Additive manufacturing enabled the creation of intricate internal channels, lightweight lattice structures, and integrated assemblies, significantly reducing mass and production lead time. The direct CAD-to-print workflow preserved design accuracy and facilitated rapid iteration, allowing engineers to complete design revisions and physical prototypes within hours. Powder-bed fusion technology, in particular, produced components with minimal support structures and high-quality surface finishes—approximately 250 Ra—with minimal manual post-processing time required per part.

The experience gained from XB‑1 reinforced the broader benefits of additive manufacturing. Beyond speeding up production, it provided unparalleled design flexibility, optimized structural weight, and improved supply chain efficiency. Applying these lessons to the current sprint core phase, Boom is leveraging the 193 test parts to de-risk critical engine components and validate the end-to-end manufacturing process. This includes confirming performance tolerances, thermal behaviors, material properties, and seamless integration within engine subsystems—all before investing in full-scale hardware builds.

As the program advances toward full sprint core production, Boom will increasingly rely on diverse additive manufacturing technologies. These include metal powder-bed fusion, directed energy deposition, and cutting-edge polymer printing.