Air Force Sets Date To Fly Mach-6 Scramjet

coondoggie writes "The US Air Force said it was looking to launch its 14-foot long X-51A Waverider on its first hypersonic flight test attempt May 25. The unmanned X-51A is expected to fly autonomously for five minutes, after being released from a B-52 Stratofortress off the southern coast of California. The Waverider is powered by a supersonic combustion scramjet engine, and will accelerate to about Mach 6 as it climbs to nearly 70,000 feet. Once flying, the X-51 will transmit vast amounts of data to ground stations about the flight, then splash down into the Pacific. There are no plans to recover the flight test vehicle, one of four built, the Air Force stated."

Old Tech but New Challenges

[BrightSpark]

The concept is not new but it is very difficult to turn it into practice. These guys at University of Queensland and others have been working on this for several years and have trialled severa prototypes before. http://www.uq.edu.au/news/index.html?article=20718 [uq.edu.au] Not bad without military budgets - beat them to the punch!

Re:Always money for military space projects

[rubycodez]

"We annually spend on military security more than the net income of all United States corporations.

This conjunction of an immense military establishment and a large arms industry is new in the American experience. The total influence -- economic, political, even spiritual -- is felt in every city, every State house, every office of the Federal government. We recognize the imperative need for this development. Yet we must not fail to comprehend its grave implications. Our toil, resources and livelihood are all involved; so is the very structure of our society.

In the councils of government, we must guard against the acquisition of unwarranted influence, whether sought or unsought, by the military-industrial complex. The potential for the disastrous rise of misplaced power exists and will persist.

We must never let the weight of this combination endanger our liberties or democratic processes. We should take nothing for granted. Only an alert and knowledgeable citizenry can compel the proper meshing of the huge industrial and military machinery of defense with our peaceful methods and goals, so that security and liberty may prosper together.

Akin to, and largely responsible for the sweeping changes in our industrial-military posture, has been the technological revolution during recent decades.

In this revolution, research has become central; it also becomes more formalized, complex, and costly. A steadily increasing share is conducted for, by, or at the direction of, the Federal government.

Today, the solitary inventor, tinkering in his shop, has been overshadowed by task forces of scientists in laboratories and testing fields. In the same fashion, the free university, historically the fountainhead of free ideas and scientific discovery, has experienced a revolution in the conduct of research. Partly because of the huge costs involved, a government contract becomes virtually a substitute for intellectual curiosity. For every old blackboard there are now hundreds of new electronic computers.

The prospect of domination of the nation's scholars by Federal employment, project allocations, and the power of money is ever present and is gravely to be regarded.

Yet, in holding scientific research and discovery in respect, as we should, we must also be alert to the equal and opposite danger that public policy could itself become the captive of a scientific-technological elite. " -- Dwight D Eisenhower, 1961

Re:Great step forward

[Cheezymadman]

Without training, the average human can withstand 15-20 Gs for a few minutes without experiencing any ill effects (aside from nausea and such, obviously). That's horizontal Gs, by the way. Pure vertical force, you're looking at a max of 3-5 Gs before gray- and black-outs.

Reconnaisance

[jamrock]

I don't see much of a military need for this tech, however, when we've had military launch capability that could reach any location on earth well within a day, including the time it takes for authorization, for close to half a century.

You're presuming that it's solely for weapons delivery. The first application that came to my mind was reconnaisance. It's all well and good to be able to deliver a warhead to "any location on earth well within a day", but intel as near-real time as you can get it is just as critical to the military, and the ability to get sensors over an area of concern as quickly as possible is immeasurably valuable. That's the reason the SR-71 Blackbird was built, and it performed it's mission admirably for decades.

Re:Old Tech but New Challenges

[MichaelSmith]

A Talos-Castor rocket combination propelled the HyCAUSE engine to a height of about 450km, with the first stage Talos dropping off after six seconds, and the second stage Castor taking the scramjet engine to an experiment in the final seconds of the flight. [uq.edu.au]

Re:Always money for military space projects

[Fallen Kell]

You have no clue... A mach 6 fighter/bomber would very much be useful in the armament. At that speed it can outrun most missiles used to shoot it down. Very few weapons platforms can track and engage an aircraft flying faster than mach 4 at the moment, let alone something flying mach 6. There are only a handful of missiles (surface-to-air or air-to-air) which can even travel mach 6 or faster, which means you can only attach from a forward vector and once it passes your position or is flying away from you, your missiles will not be able to catch the plane. This assumes that your radar system can even detect a plane that fast and can instruct the missile how to intercept the target.

Re:Aurora

[Anonymous Coward]

The linked photo is of a prop plane [wikimedia.org] used for the movie "Stealth". Sadly not a real aircraft, it does look like it'd be fast though!

Re:Aurora

[Libertarian001]

Seriously? Please tell me you're kidding. That's the F/A-37 Talon from the movie, "Stealth." I know it was a lousy movie, but, come on.

Re:Aurora

[Anonymous Coward]

That plane is from the movie STEALTH:
http://en.wikipedia.org/wiki/File:ASW_Fake_FA37_1.jpg [wikipedia.org]
http://en.wikipedia.org/wiki/Stealth_(film) [wikipedia.org]

Re:Great step forward

[RockoTDF]

It was banned on and off throughout its career. It didn't do too many supersonic flights in the states even when it was allowed. It wasn't even that loud on takeoff, and flew higher than regular airliners.

Re:Great step forward

[RockoTDF]

According to the wikipedia article on the concorde, it was actually quieter than many other models in service at the time.

Re:Great step forward

[RockoTDF]

15 to 20? Citation needed there. That is between 2000-3000 lbs on a 150 pound person. Fighter pilots have to train to maintain high Gs, which even then they only pull for a matter of seconds (at the highest levels) when flying, and for maybe a few minutes in a centrifuge. They have to wear g-suits to avoid blacking out. Early on during the Korean war, the Mig pilots from the North didn't have g-suits. So the American pilots quickly figured out that if you just get them to follow you into a very high g turn they would black out and crash.

Re:Great step forward

[amorsen]

I don't see this as cutting air drag, which goes up to the fourth power as speed increases

In a flow without flow separation, drag increases linearly with speed. With flow separation, drag increases ~ with the square of the speed. Nowhere near the fourth power in either case.

Re:Great step forward

[Richard_at_work]

It seriously annoys me that people take Mythbusters psuedo-scientific results and applies them to everything possible - they used the F/A-18A, which at 35,000lb would be 1/10th the weight of Concorde (and I bet that the F/A-18A in the test had a significantly lower loading than that), and the test was done at significantly lower speeds than Concorde cruises at.

I am doubtful as to the validity of the results the Mythbusters came up with, as it was already proven during the Oklahoma City Sonic Boom tests in 1964 caused hundreds of broken windows (windows in skyscraper structures were broken routinely over the course of the tests, with no significant occurances before and after the tests - make your own conclusions).

Apart from physical damage, you seriously have to consider the environmental impact - can people live with loud bangs as a routine? Again, the Oklahoma City tests showed that no, people are not willing to put up with routine sonic booms as they are disruptive and invasive.

Re:Great step forward

[Pinckney]

Again, horozontal Gs (e.g. normal to the spine). Fighter pilots experience vertical Gs (parallel to the spine). From wikipedia "Early experiments showed that untrained humans were able to tolerate 17 g eyeballs-in (compared to 12 g eyeballs-out) for several minutes without loss of consciousness or apparent long-term harm."

You might want to take a look at the Gloster Meteor F8 Prone Pilot [wikipedia.org], an experiment to control a plane from a prone position to better cope with Gs.

Re:Old Tech but New Challenges

[pushing-robot]

That's a different kind of test, and the X-43a beat them to it by a few years. [nasa.gov]

On top of that, the GGP claims "Not bad without military budgets" when your link states "The launch was a collaborative effort between the United States' Defense Advanced Research Projects Agency (DARPA) and the Defence Science and Technology Organisation (DSTO), also representing the research collaborators in the Australian Hypersonics Initiative (AHI)."

Not to belittle their efforts, mind you; it's a spectacular project and I wish them the best. Just correcting bad information.