OK, How do You Militarize it Then?

One of the bad things about spending a few decades of your life in the military, is that when new things come along, there is always a voice in the back of the head that asks, "How can the military use this?"

Sabre engines for commercial air travel can go from zero to five times the speed of sound, and up to 25 times the speed of sound for space travel.

Experts believe hypersonic air travel could enable people to one day journey anywhere in the world within four hours. At Reaction Engines, based in Oxfordshire, they think this could be a reality within 10 to 15 years.
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The uniqueness of Reaction’s brainchild is largely founded on an ability to accommodate both space and air modes of travel in one engine.
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“Time is critical. What we’ll see with hypersonic air travel, and it’s clearly a long way out there, is that it gives people that option of travelling anywhere in the world within four hours. That would be a fantastic offering and we believe there is a market for that.

“This is a really versatile propulsion system that we’re developing. It is an air-breathing rocket engine that can go from zero to five times the speed of sound and for the space-access variant, 25 times the speed of sound, and has a huge range of operation. The other advantage of this engine is that it’s highly scaleable.”

The ability to up or down-size the concept is undoubtedly a trump card. Reaction has already studied a large “civil high-speed air transport vehicle”. It seats 300 people, on a par with larger versions of Boeing’s twin engine 787 Dreamliner.

“There would be a business case for a vehicle of that nature,” Thomas contends.

Ummmmm ... yes there is.

Global strike with the response time almost on par with an ICMB with a man in the loop to the terminal end? Rapid ISR ... the manned and unmanned options are huge. LEO satellite replacement, repair, and ... ahem ... "retrieval"

300 seats? Can you say "Hypersonic airborne?" Interesting tool. When operational, plenty to play with. Put Skunkworks on it.