Well NASA’s new toy the Scramjet has broken the old world record for flying 7 times the speed of sound…now it flies nearly 10 times the speed of sound. Yesterday it reached mach 9.6
My questions are quite easy: What are the practical uses for such a jet? Military or non-military? I would assume this thing could not carry humans for quite a while…I know it looks cool, but why do we need to spend 230 million on R&D with this thing? What are the practical uses? Fed-ex maybe would want one… 
I suppose it’s more muscle flexing than a military necessity. It must have cost a fortune. I know how I’d spend that money…
For the cost of just a couple of our ultra fighting planes, we could make veteran’s benefits much better;
We could raise the standard of living that most military personnel live to above the poverty level, which is where so many of them are right now.
We could invest in personal safety gear that would help keep these guys alive
Or, we could pump that money into more peaceful approaches to the world’s problems.
Well…no research is really wasted. The knowledge and technology are always useful somewhere. What I think NASA is working on is tech for a different reusable launch vehicle. If you can launch from a higher altitude, you save weight of fuel and such. I can see them developing a scramjet that drops from a mothership, zips up into LEO and deposits a satellite, then returns to earth. Cheap, easy, reusable.
Besides, it looks cool. 
Yeah, I gathered it was more intended to aid bringing space launches down in cost eventually–it’s not specifically a military thing. In the long term, cheaper space launches is a Good Thing.
Could this, say, translate into subsonic jet engines that are smaller & lighter?
Better heat-resistant alloys?
Better control systems?
The best way to develop a series of new technologies is to :
[ul]
[li]Set a goal–Mach 10, for example.[/li][li]Develop the core technology to reach that goal–the new engine[/li][li]Develop the bold new problem-fixing techs you would never have dreamed of–new contols, fuel, sensors, plastics, alloys, etc.–without trying to reach the goal[/li][li]Watch the spin-off benefits bloom like flowers.[/li][/ul]
Why not use the money to buy dollies for all the poor little girls in the world?
Seriously, NASA’s budget is essentially completely separate from the military’s. It’s not as if every dollar spent by NASA is a dollar taken away from those other worthy causes you mention. The argument you make about priorities could be made equally well in favor of the scramjet research: Why should the government give a special tax break to importers of Chinese ceiling fans instead of spending the money on scientific research?
The scramjet is a new propulsion technology. The basic idea is that a vehicle that would normally carry its oxygen with it could instead scoop oxygen out of the air and thus increase its efficiency. Like almost any technology, it can be used to help people or kill people. Maybe in 30 years a scramjet-powered vehicle will rush a human heart from the other side of the world to be transplanted into the failing body of some great humanitarian.
Silenus had it right. The scramjet was a first step in developing a replacement/complement to the Shuttle. The ultimate goal was a reusable launch vehicle for low earth orbit and relatively small man-rated payloads, that was a lot cheaper to operate and turn around.
The scramjet was theoretical for a long time, and the May flight was the first successful attempt at flying. Yesterday’s flight is the last, because the program was cancelled in favor of the new expendable vehicles for the Mars initiative.
There are other non-NASA scramjets in development, and the leading project expects a flight in June 2K5. That is a university project, and another one is commercial. More power to them, and I work for NASA.
No benefit to subsonic turbines, because a scramjet has no moving parts.
Better materials? Heck, yea.
Better controls? Cetainly.
The spinoffs will be enormous. I actually expect Burt Rutan to get in on the action for the X-Prize follow-on, which is private orbital vehicles.
We do, in fact, need something that goes Mach 10. We’re now one step closer to traveling close to the speed of light.
I saw a program on the Science Channel that NASA and other organizations are eager to keep increasing the speed of air and space craft for that purpose.
Sorry, I don’t have a cite right now.
An air breathing rocket doesn’t really have much application to moving spacecraft near the speed of light. It might have an impact on launch costs, self guided bombers replacing missiles or regular air flights but that’s about it.
I think you misunderstood. While Mach 10 is “closer” to the speed of light than aircraft have gone before, it’s not really a meaningful measurement of progress. It’s like saying that when I go from sitting in a bathtub to sitting in a wading pool I’m one step closer to swimming around the world. To get to the speed of light, NASA needs to do more than just incrementally increase the speed of aircraft; they’ll need an overhaul of modern physics.
Of course, none of that means that what they’re doing now is without worth.
Um, well, I kinda said it jokingly in a trekkie geeky sort of way.
Because Supersonic Compression Ram Jet is a really cool acronym?
It’s really a means of simplifying & cost reducing the machinery needed to get a vehicle to space, although not necessarily “orbit”. It can replace a rocket stage, and unlike disposable rocket boosters or “stages”, it remains on the aircraft, and does not require the vastly complicacted pump & turbo-machinery of a rocket engine, like the shuttle’s. It has virtually no moving parts, and can be turned around by just gassing up.
Although it can’t propel a craft to orbital velocity or altitude, and rocket engines (engines that have their own oxygen) are needed above the atmosphere for maneuvering, even a “sub-orbital” flight has some very desireable characteristics:
From a civilian application, you could have a “sub-orb” aircraft that can do London-Hong-Kong in a few hours direct flight, say the same time as London-Frankfurt, or New-York - Tokyo in the same time as New-York Chicago. Those long, 12-15 hour flights are a huge pain for frequent travellers, even with all the comforts of first class and the attentions of beautiful & compliant Singaporean attendants. There would be a big market for such flights.
From a military perspective, the advantage is even more pressing. The US strategic bombers like the B2, because of their cost, “degree of secret-ness”, and the increased political difficulty of basing them in other countries, have now been based solely in the continental US. This meant 24 hour round trip flights for the crews flying missions in the gulf area, with multiple, tricky, air-to-air refuellings. Imagine a strategic bomber that could leave a base in Nevada, drop two to four 1- 2 thousand lb. J-DAM bombs on the other side of the world, flying at altitude and speeds that no known interception method, except perhaps anti-sattelite weapons, can touch, and return to base in 6 hours. I can guarantee you that such a scenario is giving someone in Beijing heartburn right now…
Another “political” advantage is that if you’re flying in space, technically you’re not in anyone’s “airspace”…
Hope that helps exlain the need, although it may not satify the “baby-medecine-not-bombers” crowd…
Anyone forget the recent attacks on the USA, more commonly known as 9-11?
Now that we know this mode of attack, perhaps a manned or remotely controlled jet capable of M-10 be of defensive use in a similar situation.
Using your thinking the airplane would never have been invented, nor the lightbulb, or the telephone, or the steam engine, or the …
A spaceship which can land AND take off like a regular airplane.
A craft with only a fraction of the internal mass and volume allocated for liquid oxygen.
Here’s my idea for a three engine craft:
A turboramjet (like that found on the SR-71 Blackbird) to go from dead stop to mach 1.5+ on turbojet afterburner, then up to mach 3 on ramjet power.
Scramjets take the craft from mach 3 to 10.
Finally, an internal rocket engine…or an oxygen line to a jet’s combustion chamber…finally take the craft from mach 10 to 20+…orbital velocity.
Travel 12 time zones in 2 hours? Damn.
Two words: PIZZA DELIVERY
A rocket needs to carry a fuel and an oxidizer, a huge percentage of which is used to get the rocket above the atmosphere and up to near orbital speed.
The big advantage of a scramjet for this application is that it doesn’t need to carry an oxidizer - instead, it uses the air.
Consider SpaceshipOne, which just won the X-prize. It managed to get to space (not orbit) with a small amount of fuel because it was carried up to 40,000 feet and was already going a couple of hundred miles per hour when it was dropped. 40,000 feet puts it above 75% of the atmosphere, meaning low drag, rapid acceleration.
Now imagine if you had a plane that could ignite its rocket motor not at 40,000 ft and 200 mph, but at 100,000 ft, going 7,000 mph. It wouldn’t need that much more fuel to attain orbit - it’s already carrying half the velocity it needs, and it’s above 90% of the atmosphere already. So a Scramjet is a viable method for reducing the cost of attaining orbit.
Could you use rail gun tech to get your ship up to the speed needed for the scram to work? Just thinking with the keyboard.