For I have slipped the surly bonds of Earth . . .

[unixronin]

. . . and left'em WAY behind in the dust, this time.  dafydd found this press release on the first successful powered flight of NASA's X-43A scramjet research platform, also known as Hyper-X.  After being boosted to around 3,500mph (5,600kph) and 100,000 feet by an Orbital Sciences Corporation Pegasus air-launched booster, the X-43A made a 10-second powered flight, during which the 2,800lb craft burned about two pounds of gaseous hydrogen fuel, followed by a six-minute unpowered glide to splashdown in the Pacific.  It isn't known at this time exactly what speed the X-43A achieved, but it is designed for speeds approaching 5,000mph (8,000kph)

This is the first ever controlled free flight of a scramjet-powered vehicle and, just by the way, has without the slightest question shattered all existing maximum-speed records for air-breathing vehicles.

Update:

It is now being reported that the X-43A achieved 4,780mph (7,700kph), or around Mach 7, more than twice the previous air-breathing record of Mach 3.2 held by the Lockheed SR71.  This means the X-43A has also broken the X-15's Mach 6.7 record under rocket power, making it (unless I'm badly mistaken) the highest speed ever attained by any winged atmospheric vehicle of any kind.  (The Shuttle attains higher speeds, but does so on the way to and from space; the Martin-Marietta Sprint ABM was also faster, but Sprint is little more than a conical ablative fairing wrapped around a nuclear warhead and the biggest, most powerful solid rocket motor available.)

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• Find dafydd's original post here.
• Scramjet is short for supersonic combustion ramjet, so called because the air-fuel mixture is still supersonic as it passes through the combustion chamber.  This simple-sounding thing is actually stunningly difficult to achieve without the engine blowing out like a candle in a high wind.
• I worked on the design of the onboard computer system for the Pegasus in association with Dryden Flight Research Center while I was at Eastern Washington University, including wire-wrapping the first prototype CPU board, which makes it particularly cool for me every time something cool flies on a Pegasus.
• Sprint's first stage generated 650,000lb of thrust for 1.2 seconds, igniting just after the missile was ejected from its silo by a gas-generator and captive piston, and accelerating Sprint at 100 G.  According to some reports, the missile was already supersonic when it exited the silo.  The second stage ignited 1.2 seconds into flight, and Sprint exceeded Mach 10 within four seconds of second-stage ignition.  It is reported that the radar-targeted command-guidance system had to be detuned during testing, because Sprint was so accurate it often physically hit incoming re-entry vehicles.  Even this was slow compared to another ABM, HiBEX (High-G Boost EXperiment).  Intended for last-ditch interception of incoming re-entry vehicles below 20,000ft altitude, HiBEX was designed to exit its silo within a quarter second and accelerated at 400 G.  Reportedly, ring laser gyros were developed by ARPA for HiBEX because no mechanical gyro could be spun up fast enough.

Comments

[ilcylic.livejournal.com]

Holy fuck that's cool.

I want one.

I want one that can bootstrap, though. Hydrogen powered turbines, hydrogen afterburners, and a tuneable RAM -> SCRAM. Essentially, an airplane that can take off from a runway, run up to speed, and put itself in high orbit.

Wow. 400Gs. That's a lot. All that effort devoted to working on stuff that can kill people, or deal with people trying to kill us. I just wish we'd put that much work into building shit to help people instead. With that kind of launch capacity technology, I bet we could have made space a truly viable thing by now.

*weeps for his species*

-Ogre

[unixronin.livejournal.com]

That would rock much ass, but a hybrid engine that can operate in turbine or scramjet mode would be fantastically difficult to build. A rocket/scramjet or even rocket/ramjet/scramjet hybrid might be more feasible. I know there's been technical discussions of the feasibility of a hybrid engine that could operate in either ramjet or scramjet mode, and also of scramjet/rocket hybrids. My understanding is you need about Mach 5 to light off a scramjet, and I know there's missiles with ramjet sustainers that hit about Mach 5, so it sounds like it should be possible to build a hybrid that takes off on rocket power, switches over to ramjet mode at about Mach 0.7, accelerates up to about Mach 5 on ramjet power, transitions smoothly to scramjet mode, continues to accelerate up to about Mach 10 or 12, then switches back to rocket power for the final dash to orbit.

HiBEX was technically very interesting, but not very practical. It only had enough fuel for a few seconds of flight, and a typical mission profile scenario called for intercept of an incoming RV at about 10,000 feet, but detonating that low the missile's own high-neutron-flux warhead would kill every living thing within a three-mile radius anyway. It'd really only be of any use for defending crucial hardened military targets. The 400G motor doesn't have any practical application for spaceflight involving humans unless you want them to arrive in orbit in a jar.

But that said, yeah, if that much ingenuity and development money had all gone towards getting humanity peacefully into space, and to STAY, not just as a publicity stunt to show up the other guys and do a little token science while we were there... The problem is, back in those days the Soviet Union's official foreign policy was "We will bury you", and the crazy fuckers on both sides thought that if it came down to it, they could start a global thermonuclear war and not only survive, but win. Fortunately, no-one was ever quite crazy enough to actually push the button, but it's recently been revealed that it came frighteningly close -- apparently if the Russian nuclear installation on Cuba had been successful, Castro was ready and willing to sacrifice Cuba by launching a nuclear first strike against the US, as his ultimate service to the cause of international communism.

Still, at least now we're starting to see private ventures into space. Maybe in our lifetimes we'll be able to get governments the fuck out of space -- or just get into space and declare ourselves independent, and tell all the professional mudslingers and till-robbers to fuck off and die.

[ilcylic.livejournal.com]

Ah. No, I meant a vehicle with multiple engines. So, you've got your big RAM/SCRAM in the middle, with a pair of turbines on the sides.

And yes, I didn't mean the specific 400G booster would be useful for anything, but the brainpower it represents, if turned to more peaceful purposes, could have done wonders for getting us out there.

-Ogre