Synergetic Air-Breathing Rocket Engine

SABRE – Synergetic Air Breathing Rocket Engine – is a new class of engine for propelling both high speed aircraft and spacecraft. SABRE engines are unique in delivering the fuel efficiency of a jet engine with the power and high speed ability of a rocket.

Unlike jet engines, which are only capable of powering a vehicle up to Mach 3, three times the speed of sound, SABRE engines are capable of Mach 5.4 in air-breathing mode, and Mach 25 in rocket mode for space flight. They are simply going to revolutionise the way we travel around the globe, and into orbit. Like jet engines, SABRE can be scaled in size to provide different levels of thrust for different applications which is crucial to our success – it's going to enable a whole generation of air and space vehicles.

With a clear ground test and development programme.

There are three core building blocks to the SABRE engine, the pre-cooler, the engine core and the thrust chamber. Each of these systems can be developed and validated using ground based demonstrations, which saves cost and time relative to flight test, a design feature that benefitted the development of the propeller and jet engine. We have demonstrated each of these independently over the last four years, beginning with a high temperature test of the Pre-Cooler.

To read about the fully validated HTX test results click here


Single-Core SABRE Engine:

Design (Mach 5) Specific Impulse: 28000 N s /kg
Sea-Level Static Net Thrust: 200 kn

Air breathing mode:

Speeds: Mach 5.4
Net thrust (max): 350kn
Core Air Mass flow: 125kg per second

Rocket Mode:

Speeds: Mach 25
Net Thrust (max): 500kn
Vacuum Specific Impulse: 4500 N s /kg


Core engine demonstrator

A complete engine ‘core’ that can be tested at ground-level static conditions, right up to Mach 5, and 25 km altitude.

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Flight applications

SABRE engines could allow aircraft to fly much faster than traditional jet engines –  in various conditions.

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In addition to being a key element of SABRE, the pre-cooler technology also finds application in conventional gas turbine jet engines. 

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