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High-performance propulsion

Liquid rocket engines and solid rocket motors optimized for high performance, diverse capability, and proven reliability.

The Ursa Major difference

Made to standards that set a new standard

We meticulously design, craft, and test our engines to achieve unmatched quality and reliability — and it’s all backed by the consistent stream of test data logged at our in-house facility.

Design
We use cutting-edge design techniques to create parts that simply couldn’t exist even ten years ago.
Fabrication
Additive manufacturing reduces overall part count and development time while allowing for rapid design, manufacturing, and iteration.
Testing
Ursa Major propulsion systems are developed and tested in-house, allowing for unmatched control over test scheduling.

Liquid rocket engines

Staged combustion
High-performing engine cycle in a compact design is our baseline
Reusability
Single engines capable of multi-mission use and extended duration applications
Thrust vector control
Precise gimbal maneuvering and control
Active throttle range
Allows for Max-Q throttling, g-limit throttling, and mission-specific thrust profiles
Single-mission restarts
Allows for efficient orbit-changing burns, de-orbit burns, and Stage 1 recovery
Custom burn duration
Allows for flexibility in mission planning and total impulse
Draper

In development: A flexible liquid engine with the storability of a solid motor


Suitable for tactical hypersonics, missile defense, in-space propulsion

Hydrogen Peroxide / Kerosene
Propellants
4,000 lbf
Thrust, Sea Level
Closed Catalyst Cycle
Hadley

In production: America’s first oxygen-rich staged combustion engine 


Suitable for small launch, hypersonics

Lox / Kerosene
Propellants
Oxygen-rich
staged combustion
5,000 lbf
Thrust, Sea Level
6,500 lbf
THRUST, VACUUM VARIANT
Ripley

In development: Highest performing kerosene engine ever built in the U.S.


Suitable for small to medium commercial launch

Lox / Kerosene
Propellants
Oxygen-rich
staged combustion
50,000 lbf
Thrust, Sea Level
Arroway

In design: The future of American engines for heavy lift


Suitable for medium to heavy launch, national security launch, RD-180 replacement

Lox / Methane
PROPELLANTS
Staged Combustion
200,000 lbf
Thrust, Sea Level

Solid rocket motors

Driving speed and uniformity across motors with non-traditional manufacturing, as the U.S. faces a critical shortage in munitions.

Ursa Major solid rocket motors

Tactical, Defense, Hypersonics

Ursa Major solid rocket motor designs are optimized for manufacturing while delivering full performance.
Surge capability
Rapidly scale motor production leveraging common manufacturing production equipment and minimal tooling
Adaptability
One-click changeover to different casings on a single additive machine
Lower cost & fewer parts
Ursa Major’s processes have simplified the complex and labor-intensive process of motor manufacturing to reduce both part count and assembly tasks.
2-22" Diameter
Tailorable Thrust Profile
Composite Solid
Propellants
Recent News
Hadley engine test in May 2023
Blog post
Engine Test Roundup for Q2 2023
Bloomberg Ursa Major
Coverage
US Air Force expands hypersonic arsenal with Ursa Major pick
Ursa Major Hadley engine qualification test
Blog post
Hadley: Three variants of a category-defining engine
defense news ursa major
coverage
The Pentagon’s embrace of startups could fuel hypersonic tech

Get in touch

Interested in how Ursa Major can advance your mission?
Let's Chat