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USAF Scramjet Hits Mach 6, Sets Record
s122604 writes "The [X-51A Waverider]'s scramjet engine accelerated the vehicle to Mach 6, and it flew autonomously for 200 seconds before losing acceleration. At that point the test was terminated. The Air Force said the previous record for a hypersonic scramjet burn was 12 seconds. Joe Vogel, Boeing's director of hypersonics, said, 'This is a new world record and sets the foundation for several hypersonic applications, including access to space, reconnaissance, strike, global reach and commercial transportation.'"
Proof of concept. Scientists can only go so far on theory ( and it's impressive how far they do go ). At some point their research hits a point where they need to perform experiments.
Mod me down with all of your hatred and your journey towards the dark side will be complete!
Keep in mind that at mach six 200 seconds is 400 kilometers. That's already enough range to make a useful weapon (and yes I realize there was some acceleration time in there). Heck, that's already longer range than the most advanced missiles that many countries have. Increase the stability to just 10 minutes of burn time and you've got a missile that can go 5% of the way around the world.
So not only does this do Mach 6, but it also uses its own sonic booms to help with propulsion? Or did they just choose Waverider because it sounds neat?
http://en.wikipedia.org/wiki/Waverider
Don't know something? Look it up. Still don't know? Then ask.
Commercial applications do usually follow. Whether or not you agree with it, military research has led to an enormous number of scientific advances that were initially used by the military but later disseminated more broadly. Jet engines, the Internet, cryptography, GPS, nuclear reactors, etc. Mach 6 might be inefficient overkill for Earth-side transportation, but it may provide a viable means of launching spaceflights one day.
$_ = "wftedskaebjgdpjgidbsmnjgcdwatb"; tr/a-z/oh, turtleneck Phrase Jar!/; print
Boeing announcement here:
http://boeing.mediaroom.com/index.php?s=43&item=1227
"In its first flight attempt, the Boeing [NYSE: BA] X-51A WaveRider today successfully completed the longest supersonic combustion ramjet-powered flight in history -- nearly three and a half minutes at a top speed of Mach 5."
My understanding is that it didn't reach the 300 seconds Mach 6 burn it was hoping for. 200 seconds and Mach 5 isn't all that bad though...
More here:
http://www.theregister.co.uk/2010/05/27/x51_first_shot/
wot no sig
Are you talking about the scramjet or the events at Kitty Hawk in 1903?
Because Wilbur already had the first chance, Orville took his turn at the controls. His first flight lasted 12 seconds for a total distance of 120 feet (36.5 m) - shorter than the wingspan of a Boeing 707.
Questions
According to the article there's three more vehicles which will be tested in the fall.
Scramjets aren't exactly easy to test in the lab.
Hell, even normal jet engines are tough to test. Have you seen the equipment used to keep those things stationary while testing them? Holy fuck .
Living With a Nerd
Fine. Except for jet engines, the Internet, cryptography, GPS, and nuclear reactors what has the military done for us?
No it isn't. Mach is the speed sound travels in a medium (the atmosphere). As there is no atmosphere in orbit, you can't associate a mach speed value to orbital velocities.
-SaNo
Little plastic Army Men
Living With a Nerd
Except they're not recovering these vehicles for analysis.
Not only that, but you can't always be sure which part is the weak link, what will break. A few tests at hypersonic is guaranteed to make an engineer say "ok, that's an issue we weren't aware of", and confirm much of what they already knew. They may have to make some part that they *thought* would be ok out of a different, stronger alloy, etc. Of course, at this speed, every tiny error in engineering is amplified, as at Mach 6, you cross a lot of real estate in just a few seconds, so the word "precision" doesn't adequately describe the level of perfection required in the test system build.
Being a pioneer at anything guarantees surprises, and best of all, learning new things.
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It's amazing to me that they can make a machine who's parts are GLOWING they are so hot and the metal still functions without failing.
A work that expires before its copyright never enters the public domain and thus enjoys eternal copyright protection.
Mac 5 melts aluminum steadily
Mac 6 melts steel
And don't forget that keeping this friction heat down also requires a good deal of power.
Hello,
The story is in error. Per this link, the plane only hit Mach 5, not Mach 6. This is still a pretty successful test, however.
Link: http://www.msnbc.msn.com/id/37377401/ns/technology_and_science-space/
--PeterM
Radial Engines, Kevlar, Ceramic Technologies, Radar, Microwaves, Food Preservation, Someone else keep this going.
Why is it so hard to only have politicians for a few years, then have them go away?
Others have expressed the detail, so I won't be redundant, but the J58 is on the extreme end of Jet technology even today, and that was the point of my analogy. Those airliner engines you mention produce more thrust and are more economical to operate and to maintain, by a very healthy margin. However, they are only good up to about 500 kts or so, as opposed to the 2000+ kts the J58 is capable of. Nor will they function at all about 60000 feet, whereas the j58 will at full or nearly full thrust. So, in comparison, modern airline engines of which you speak are not in the same class of tech, nor would you expect them to be, since their purposes are far different. On a side note; it's note related to the tech of the engines themselves, of course, but those airline engines also will never push as pretty an airframe through the air, wich disqualifies them on the asthetic front too.... {smile}
A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort.
Even at Mach 3, you want a layer of foam to avoid burning.
Let's not stir that bag of worms...
The temperature of objects produces (from what i recall of physics) black body radiation - meaning it produces light wavelengths. Just because we associate melted iron being red hot, doesn't mean other metals melt when they start to glow. It just means they are hot enough to produce enough black body radiation that we can see. Look at mercury for example as an opposite.
..........FULL STOP.
I think you misunderstand his point (or perhaps I am giving him too much credit for asking a really good question). Mach speeds are a ratio of the speed of the aircraft to the speed of sound. Mach 6 therefore means "six times the speed of sound". OK, nothing difficult there; most people here probably knew that already. Here's the rub: what is the speed of sound? Hint: it's not the same at sea level and at the 0.1Mm you mention, because the speed of sound varies with the density of the atmosphere. In other words, Mach 6 at sea level (~4500 mph) is not the same speed as Mach 6 at, say, 100,000 feet above sea level (~4100 mph).
MCSE? No, sir...I don't do Windows. Yes, I am an idealist. What's your point?
you mean in the autumn?
or in the spectacular screaming descent towards land?
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
It's all part of the Prompt Global Strike program. Eventually the goal is to have scramjet powered missiles with a range of 12000+ miles. Allowing you to fire an obviously non-nuclear missile from Kansas to North Korea and have it hit the target in less than 3 hours. Basically, even launching a B2 for a direct strike takes days or weeks. Refueling planes need to be put into the air, mission plans drawn up, clearance over foreign airspace cleared, pilots briefed, etc. They want to be able to say "Fire" and have the missile in the air within minutes and at target within hours; with the added benefit of not putting any American lives in harms way.