Slashdot Mirror
USAF Hypersonic Scramjet Successfully Scrams
cold fjord writes "It looks like another milestone for hypersonic flight has been reached. From the story: 'The final flight of the X-51A Waverider test program has accomplished a breakthrough in the development of flight reaching Mach 5.1 over the Pacific Ocean . . ."It was a full mission success," said Charlie Brink, X-51A program manager for the Air Force Research Laboratory Aerospace Systems Directorate. The cruiser traveled over 230 nautical miles in just over six minutes over the Point Mugu Naval Air Warfare Center Sea Range. It was the longest of the four X-51A test flights and the longest air-breathing hypersonic flight ever. . . This was the last of four test vehicles originally conceived when the $300 million technology demonstration program began in 2004. The program objective was to prove the viability of air-breathing, high-speed scramjet propulsion. The X-51A is unique primarily due to its use of a hydrocarbon fuel in its supersonic combustion ramjet, or Scramjet, engine. ... The use of logistically supportable hydrocarbon fuel is widely considered vital for the practical application of hypersonic flight.'"
We haven't had a public breakthrough weapons technology as good as megaton nukes, since the 60's.
I don't think that is correct. The impact of precision guided munitions has already had a huge impact, and it continues to grow. The following except refers to events around Operation Desert Storm in 1992. At that time precision guided munitions were largely bombs and missiles, and a few expensive anti-tank artillery rounds. Now that capability is finding its way to more mundane artillery and mortars as well, not to mention much smaller missiles. The devices are becoming smaller, lighter, more precise, easier to use, and cheaper, so there will be a lot more of then in the future. A large strike by precision weapons could easily reverse the tide of battle in a way that nothing short of a nuclear weapon could in the past. Compared to nukes there are few drawbacks and many substantial advantages, such as not contaminating the battlefield and the fact that their use doesn't really have any of the political problem that nuclear weapons have.
IMPACT OF PRECISION WEAPONS ON AIR COMBAT OPERATIONS
We are writing a new and exciting chapter on air power--a chapter made possible in part by precision guided munitions (PGM). Air power advocates have long dreamed of a day when the weapon, platform, and willingness to use them properly would come together to make air power a decisive force. Today, those dreams are reality. One need only look back to our raids on Schweinfurt, Germany, in World War II to see how dramatically precision weapons have enhanced our capabilities over the last 50 years. Two raids of 300 B-17 bombers could not achieve with 3,000 bombs what two F-117s can do with only four. Precision weapons have truly given a new meaning to the term mass.
To shut down an industry in World War II, we were forced to target entire complexes because of the inaccuracy of our weapons; today we would need to hit only a couple of key buildings. What we historically achieved with volume we now can accomplish with precision. After all, the objective has never been to see how many bombs we could drop, but to produce results.
Precision weapons may also constitute a revolution in mobility. Of the 85,000 tons of bombs used in the Gulf War, only 8,000 tons (less than 10 percent) were PGMs, yet they accounted for nearly 75 percent of the damage. If we had wanted to, we could have airlifted all of our PGMs with just five C-5s or nine C-141s a day.2 . . . more
much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
It's the first success with a radically new regime of flight surface/engine. The SR-71 was the evolution of the Wright Flier pushed to its very limit (well, the ramjet represents a slight break, but not a tremendous leap).
Once you start getting a long way over the speed of sound combustion cannot propagate fast enough to push you along. Your airfoils don't work the same at supersonic speeds either.
The principles on which slower than air flight works don't really apply over about mach 3. A scramjet produces lift in a different way, the engine is based on different principles. Your engine is this bizarre thing which is formed partly by the airflow around the aircraft and much of the useful combustion/fuel heating happens on the outside in order to stop your intake melting.
A working scramjet allows evolution from that platform (ie. now that there is one to modify, you can tweak it to get the ignition speed down, the thrust up, and so on). They're also the only other option to rockets that can provide a meaningful amount of energy to a spacecraft (learn the rocket equation, then realise that your propellant in an air breathing engine comes pretty close to free to understand why this could make a big difference).
Now, ~50 years later, a missile flies at Mach 5.1 for 6 minutes. That is a 50% increase in speed in ~50 years. This is hardly the tremendous breakthrough that is claimed.
What kind of comparison is that?
The technology behind the Blackbird topped out at about the speed you mention. The technology that has made this scramjet possible is just getting started at mach 5.1.
If that doesn't convince you, bear in mind that at this level even the difference between mach 5.0 and 5.1 is rather considerable, much like the difference in required engine power between 300kph and 350kph.
..Mullah or Pope, Preacher or Poet, who was it wrote: "Give any one species too much rope and they'll fuck it up"?