Scramjet Test Successful

An Anonymous Coward writes: "The Sacramento Bee is running this story about the first powered device to achieve "hypersonic" speeds in the Earth's atmosphere. In a series of DARPA-sponsored tests, at Arnold Air Force Base in Tennessee, a scramjet engine, encased in a titanium projectile, was fired from a 130-foot cannon, at an initial velocity of Mach 7.1. The scramjet's engines then ignited, and the object moved another 260 feet, in just 30 milliseconds, before it came to rest in a series of steel plates designed to halt the flight. Peak acceleration: about 10,000 G's. Elapsed time, including cigarettes & pillowtalk: less than a second. PS: According to this nifty page at NASA, Mach 7.1 is about 5406 MPH, whereas 260 ft, per 0.03 seconds, is about 5909 MPH."

intended use

[rneches]

The idea behind these sorts of technologies (scramjets and ramjets) is to fly very efficently, especially in the higher atmosphear. The technology to beat, in this case, is non-air breathing propultion (a.k.a. rockets). Because scramjets are air breathing, it is not neccesary to bring along an oxidizer, allowing for considerable weight savings.

Because of this, scramjets are critical for efficent, practical single-stage-to-orbit vehicles. The idea is that you operate in scramjet mode until the atmosphear thins out too much to sustain combustion, and then you start adding your own oxidizer. This will effectively turn the engine into a rocket motor. With scramjets, you could build a shuttle that would actually be fairly inexpensive to operate. Also, since the most expensive part of any mission is boosting into low earth orbit, any savings in the first stages of flight would dramatically bring down to costs for any mission, but especially heavy ones (like a manned mission to Mars).

The other reason to develop scramjets is for their raw efficenty. The use fuel at a fantastic rate, but at Mach 7, the fuel per unit distance is exceedingly good. Instead of supersonic (in this case hypersonic) flight being a luxury reserved for Concorde flyers, it would become the cheap, practical way of getting around. Of course, it would only make sense for the really long flights (like Chicago to Sidny), but the implications could be trans-global flights that cost less than regional flights.

Scramjets are very, very cool, and not just because they go fast.

Sounds military to me...

[jack deadmeat]

And almost as cool as the LOSAT, which hits around 5000mph [army-technology.com]

Forget Nukes, here's the arms race

[Uttles]

OK, so there are several countries out there that have the ability to destroy the world with a few nuclear bombs... well, that's just bad publicity these days, no government would want to wipe a country like Iraq off the map for good, what about all the innocent people that live there? Even though we have the "biggest guns" here in America, we continue to try and make newer, bigger, better ones, but now instead of blowing up an entire land mass we are making weapons that will be able to hit precise targets and travel at unimaginable speeds.

So here's the problem: just like every other new military technology, other countries will eventually get it. Hypothetically, let's say Russia makes a cannon that can fire an explosive projectile from Moscow to hit the World Trade Center in NY; they probably wouldn't do that (at least I hope not) but they would sell some of those to a bunch of small rogue countries out there who don't have "political correctness" or care about the welfare of a nation's innocent people. It all seems pretty scary to me. I mean missile defense sort of loses it's significance when the missile is travelling at mach 5.

What do we do? Well I guess we'd better make sure we have the biggest, best cannons and we have a whole bunch of them so all of those other countries will be too scared to use theirs.