Posted on 12/12/2009 11:01:50 PM PST by ErnstStavroBlofeld
The US Air Force Research Laboratory's X-51A WaveRider scramjet engine demonstrator completed its first captive-carry flight under the wing of its B-52H mothership from Edwards AFB on Dec. 9. The first free flight is planned for mid-February.
The B-52 climbed to the planned launch altitude of 50,000ft during a 1.4h flight that checked out systems and telemetry. The next flight, planned for mid-January, will be a full dress-rehearsal for the first of four planned X-51A hypersonic test flights.
The Boeing-built X-51A will be released at 50,000ft over the Pacific and accelerated to Mach 4.5 by a solid rocket booster. The cruiser will then separate and its hydrocarbon-fuelled scramjet, developed by Pratt & Whitney Rocketdyne, will ignite and run for about 300 seconds, accelerating the vehicle to Mach 6.
That's the plan, anyway, and the Air Force has four shots to prove that practical hypersonic propulsion is a reality. Tests of the fuel-cooled scramjet have gone well on the ground, but a lot is riding on the X-51A. If it succeeds, missile and other applications could quickly follow. If it fails, hypersonics could be set back for years.
(Excerpt) Read more at aviationweek.com ...
For what purpose is this technology being developed?
To preserve, protect and defend the United States of Ameerica
Well, I know that.
But is it a nuclear weapon carrier to replace ballistic missiles or manned aircraft or what?
scram jet technology can replace current cruise missile motors, aircraft jet engines and possibly spacecraft luanching motors. It has multiple uses.
Hypersonic jets would move 3 or 4 times faster than anything we have in out arsenal right now. Imagine making a cruise missile that goes so fast that your enemies can’t hit it.
Practical applications include making airliners that can fly from New York to Tokyo in 2 hours. (See the “Yankee Clipper” idea proposed during the Reagan years. A working hypersonic engine could make that a reality.)
Imagine making a cruise missile that goes so fast that your enemies can’t hit it.A vehicle traveling at zero speed can "hit" a vehicle traveling at x speed regardless of the value of x. "Hitting" only requires a delta V. In fact, the faster your target goes the less "V" you have to provide to increase the energy (proportional to deltaV^2) at impact.
How do you do that economically for a commercial airliner?
I guess I could envision some sort of three stage motor. Regular jet to get you off the ground and up there; a ramjet to get you to MACH, and then the SCRAM to hyper MACH.
That's going to be one complex piece of machinery.
You just have to One: see it coming. Two: figure out it’s course and speed. And Three: put something in its path before it gets there.
At some point the amount of time and money one invests in making a sophisticated hyper-sonic weapon system exceedes that required to make unsophisticated kill devices that accomplishes one through three.
Deploying a few million ball bearings within a "probability cloud" of a sufficient diameter to encompass the max load factor (probably less than 10g) limited path of the vehicle.
So the shotgun approach.
Very valid, and a longer shot stream than your average 12GA.
I understand the concept. But your average clay pigeon isn't traveling at MACH 6+.
That's gonna be some shotgun to take that down. Not saying it can't happen, but the SCRAMjet is actually a fairly simple engine in theory. Which means that production wise, once we figure out the dynamics, materials etc., should be fairly simple and inexpensive to manufacture.
AI Targeting and flight control systems are the ones that would need to keep up. But no simple stinger/SAM are gonna take that baby down, even with a fragmentation warhead. I see the costs associated with defense of such devices, climbing.
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