SR-72?

I'm a big fan of black jets that go really fast. So I found it interesting to see this little tidbit in the Aries Blog run by Aviation Leak Week.

Anyone who follows this stuff has been hearing or read the rumors about a REALLY fast jet called "Aurora" for many years now. The rumors were exacerbated by the retirement of the SR-71 with no obvious replacement available. If I recall, the thinking at the time by the aviation masses was, "Well, they wouldn't retire it if they didn't have something to replace it with now would they?" The folly of that argument of course is that decisions made in the "puzzle palace" are always made rationally and involve nothing but the bottom line...the defense of this nation. Unfortunately, things like politics tend to creep in from time to time so what seems like the obvious course of action always isn't.

Does this mean I have some inside knowledge about "Aurora"? Oh, hell no, all I know about Aurora for sure is that they produced some really crappy models when I was a kid...other than that I don't know anything other than what I read. And with that, here's part of what Aries has to say about the SR-72...

The X-plane would be the size of a fighter and would be designed for a speed of Mach 6.5 -- 4300 mph -- at 100,000 feet. (The SR-71 Blackbird, retired in 1990, could manage up to Mach 3.3 in sprints at 85,000 feet). It would be powered by two jet engines -- bigger versions of the engine used on the Skunk Works' RATTLRS (Revolutionary Approach To Time-critical Long Range Strike) cruise missile -- integrated into ramjets.

The speed -- less than DARPA'S Falcon Hypersonic Cruise Vehicle project or the USAF's X-51 scramjet demonstrator -- is important. At Mach 6.5, the vehicle can be powered by ramjets, rather than having to incorporate a scramjet (supersonic combustion ramjet) mode into the system. It would take off from a runway and land under power, not as a high-speed glider. It can burn near-standard hydrocarbon fuel, not hydrogen or a similarly exotic propellant. It could be made from conventional materials -- even composites -- with heat-resistant materials confined to the leading edges.

This is important because the idea of the X-plane is not to prove that such an airplane can fly at 4,300 mph but that it is "doable, practical and will work like a regular airplane." (Conspiracy theorists may choose to speculate about why the Skunks regard Mach 6.5, in itself, as No Big Deal.)

For the rest go read it HERE