Rocket engine manufacturerUrsa Major‘s newest iteration of its Hadley liquid rocket engine, the H13, has passed its first hot fire tests after undergoing a series of engineering refinements and updated production methods, including a deeper reliance on additive manufacturing to streamline component production and reduce costs.
Building on the flight-proven H11 variant, the H13 is purpose-built for hypersonic missions and brings high gains in both reusability and performance. It is designed to operate across a wide range of launch and hypersonic scenarios without requiring platform-specific customization.
“Hadley is Ursa Major’s foundational engine that has already flown hypersonic several times,” said Chris Spagnoletti, CEO at Ursa Major. “With new materials and manufacturing, H13 can be reused more than twice as many times as previous variants, driving down the cost per flight while supporting new test objectives and mission profiles.”
Standardized, Cost-Driven Design for Broader Markets
Hadley is a liquid rocket engine built for hypersonic and small launch operations, delivering up to 6,500 lbf of thrust in its vacuum variant. Running on liquid oxygen and kerosene, it became the first American-made engine of its class to exceed Mach 5 and return intact, a feat accomplished aboard Stratolaunch’s Talon-A. Built with roughly 80% additive manufacturing, it has set a new bar for agile, affordable propulsion across defense and commercial markets.
The H13 incorporates advanced materials to extend service life and boost output, while in-house production of key components enables tighter control over quality and cost through additive manufacturing. Earlier Hadley versions demanded custom engineering for each application, stretching development timelines considerably.
The H13 breaks from that model by functioning as a standardized, ready-to-deploy solution for both hypersonic flight and small launch vehicles, cutting procurement lead times. Combined with cryogenic propellants and enhanced reusability, it represents Ursa Major’s most economical and capable engine offering to date.
3D Printing and Hypersonic Programs
The strategic pressure behind the H13 is straightforward: hypersonic programs move faster than traditional manufacturing can. Additive manufacturing allows complex components to be produced without dedicated tooling, iterated rapidly, and scaled without retooling entire supply chains. For defense customers, the ability to surge output or modify a design between missions is an operational need, not a preference.
Efforts across the sector reflect the same urgency to accelerate hypersonic production.L3Harrisreported a tenfold reduction in production time for key air-breathinghypersonic propulsion componentsusing large-format additive manufacturing (LFAM) combined with robotics and integrated workflows. Similarly,Hypersonix’s DART AE demonstratorused an additively manufactured scramjet engine whose intricate internal channels and cooling pathways demand precise geometry that traditional methods cannot replicate, proving that AM is in many cases the most capable answer for meeting defense demands.
Source: 3D Printing Industry
