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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.
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
Likewise you want to stop the test before failure so you can look for signs of component wear and material stress so that you know what to improve for next time. Stopping at 200 seconds and finding this out is very useful. Stopping at 201 seconds after it has exploded and you have to work out from the pieces what went wrong is not as informative.
"The weirdest thing about a mind, is that every answer that you find, is the basis of a brand new cliche" -
Except they're not recovering these vehicles for analysis.
Assuming the acceleration is modest, her facial expression aqt Mach 6 should be identical to when she's sitting on her living room sofa.
Except they're not recovering these vehicles for analysis.
That's what datalinks are for.
The SR-17 had a combo turbojet/ramjet engine, it's forseeable that an updated engine could make the ramjet-scramjet leap.
ICBMs do not do any jetting at all, its not a comparison, as they are ballistic rockets. You can think of them as flying mortars more than missiles. The closest applicable missile would be a cruise missile, but honestly, they are designed more for distance than speed. You don't need your cruise missile to get there ridiculously fast, but you do want a ridiculous range for them, at a sufficient speed to not be destroyed or give advanced warning, while still making it to the target in time for intercept.
a handful of selfish greedy people are no match for millions of selfish, greedy people -u4ya
It is almost assured that they would have happened later, though, since they didn't beat the military research to begin with.
They weren't measuring speed relative to the ground. They were measuring speed relative to itself.
Umm, I think it was stationary relative to itself.
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.
Or you just lie flat on the earth and let gravity do about the same.
Useful??? They had to use a B-52 to get into the air. Then a rocket booster to go to 4.5Mach. Then this precious little stove pipe took it to 5.0 Mach.
Yeah! How can you call that useful? And speaking of wastes of time during our war with the Japs and the Nazis, did you hear what those crazy eggheads over at Los Alamos are doing? They're trying to build a "nuclear bomb" -- but all they've managed to do so far is irradiate a bunch of scientists. How is that useful?
(/snark)
This is a *test program*, not a final product. It's designed to gather data. This was the first flight of a hydrocarbon-burning scramjet, yet it's already managed an acceleration and climb rate faster than a typical commercial aircraft -- but in conditions of orders of magnitude greater drag. It would have gone faster and higher, but it had a flameout 200s in -- again, not that unusual in a first-of-the-kind test.
Scramjets are not designed to be standalone engines. They're meant to be a "mid stage" engine to orbital rockets or a final stage for high-speed intercontinental aircraft, operating in an . For orbital craft, the scramjet craft is either part of the first stage carrier rocket which launches payloads with a small kickstage, or itself has a small kickstage for final orbital maneuvers. Initial thrust for scramjet powered vehicles is to be provided by some combination of rockets, advanced jets, ramjets, or hybrids of the aforementioned techs. A particular hybrid of interest is the "dual mode" scramjet/ramjet combination, designed to operate from around Mach 1 or so up to 1/2 to 2/3rds of orbital velocity. To get up to Mach 1, cheap droppable rocket boosters are what will probably be used, at least early on. But what's really possible is at this point still a big subject of debate, and a lot more data is needed.
Present day. Present time.
Also, Wikipedia specifies a Mach number for LEO [wikipedia.org].
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