Key component of the SABRE hypersonic engine passes Mach 5 test

Key component of the SABRE hypersonic engine passes Mach 5 test
A main application of the SABRE engine is to power the Skylon spaceplane
A main application of the SABRE engine is to power the Skylon spaceplane
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A main application of the SABRE engine is to power the Skylon spaceplane
A main application of the SABRE engine is to power the Skylon spaceplane
SABRE infographic
SABRE infographic

Reaction Engines' Synergetic Air-Breathing Rocket Engine (SABRE) has passed a major milestone, as one of its key components handled conditions equivalent to an airspeed of Mach 5 (3,704 mph, 5,961 km/h). In ground tests at the Colorado Air and Space Port, the hybrid engine's precooler handled a hotter, faster airflow than any previous jet-powered aircraft could tolerate.

The latest tests of the SABRE precooler represent a major step toward making the engine operational because Mach 5 is the switchover point when the SABRE changes from an air-breathing jet engine to a pure rocket engine burning hydrogen and liquid oxygen, making speeds of up to Mach 25 (17,521 mph, 29,808 km/h) possible.

Key to this is the precooler, which can handle air coming in with a force 25 times that of a category 5 hurricane and dampen temperatures that would melt any material that the engine core might be made of. Using recirculated cryogenic hydrogen fuel to cool incoming air, the precooler can quench the hypersonic airflow down from a temperature of 1,000° C (1,832° F) to -150° C (-302° F) in 1/20th of a second.

SABRE infographic
SABRE infographic

The recent tests follow a previous series of Hot Heat eXchanger (HTX) tests in April when the precooler handled airflows equivalent to Mach 3.3 (2,447 mph, 3,939 km/h) and temperatures of 420° C (788° F). When fully developed, the precooler will not only help power the SABRE engine for hypersonic flights and orbital launches, but also can be used in a range of automotive, aerospace, energy and industrial applications.

"This is a major moment in the development of a breakthrough aerospace technology which has seen Reaction Engines’ precooler tested at Mach 5 airflow temperature conditions, smashing through previous achievements at Mach 3.3 temperatures and paving the way for hypersonic flight," says Mark Thomas, Chief Executive, Reaction Engine. "In addition to its use in our SABRE class of air-breathing rocket engines, there are numerous exciting commercial applications for our precooler technology, which delivers world-leading heat transfer capabilities at low weight and compact size, and we are seeing significant interest from a range of potential customers and technology partners."

Source: BAE Systems

Can't wait for this bad boy to be commercialized! Hoping to snag one off the 'zon and mount it up to the back of my zero turn, baby! Should cut mowing time in at least half, right? -Tim Allen
I hope I live to see the first regular low orbit commercial flights. Europe in a couple of hours or less would be so amazing.
In 1/20 of a second, air at Mach 5 will travel approximately 250 feet. Just how long is this precooler?
Nelson Hyde Chick
The planet despertly needs for humanity to be burning less fuel into the environment and this and humans going to orbit is just going to burn more fuel and thus hasten the planet's and be extension our destruction.
Yeah, one more non-economic version of Concorde. Cant travel over population areas due to a damaging sonic boom, too expensive for all but routes popular with the super rich. What IS the point?
David Tiffany
Paul, if you have a look at the cross section, you'll see the precooler is downstream of the engines inlet (cowled spike). This does the job of slowing the supersonic air down (in the aircrafts frame of reference) to subsonic. In the process it is compressed considerably, hence why it is so hot and needs to be cooled before the core engine can handle it. For reference the limiting factor for the j58 engine that powered the sr71 was actually the temperature at the inlet of the compressor, which could reach 800 deg f at top speed.
Hey, 8.28kps is a pretty fair rate of speed.
Vernon Miles Kerr
I think @ray47 really nailed it. These type of developments are interesting because of being cool technology but — like the super-dooper yachts that often appear in New Atlas — it's really hard to get excited about something you will probably NEVER be able to enjoy yourself.
Expanded Viewpoint
David Tiffany, the cooler is Upstream of the jet engine, not downstream. When designing the J-58 bypass turbojet engine, in order to simulate the inlet temperatures it would be seeing at Mach 3, they stuck another turbojet engine in front of it! The pictures I saw of the testing were quite impressive indeed!!