DARPA Set To Blast Falcon Mach 20 Test Flight

coondoggie writes "The Defense Advanced Research Projects Agency is taking to the sky again, this time to run what it says will be the second and final test of its hypersonic Falcon aircraft, which is capable of hitting speeds up to Mach 20, or about 13,000MPH. The Falcon Hypersonic Technology Vehicle 2 is scheduled to launch Wednesday between 7:00am — 1:00 pm PDT from Vandenberg AFB, Calif., aboard an Air Force Minotaur IV rocket. The rocket delivers the Falcon to a starting point high in the atmosphere, where its engine ignite, and, if all goes well, it will blast through the air for about a half hour, DARPA says."

Comments

13,000mph?

[Skarecrow77]

wow. half-again and you're in orbit.

where do you need to go that fast?

"When the bomb absolutely has to be anywhere in the world in 30 minutes or less, DARPA is there!"

Re:13,000mph?

[HappyHead]

where do you need to go that fast?

Well, if you need to shoot down a satellite, I suppose launching a missile from something that's already going at 13000mph is easier than launching it from the ground. The only other use I can think of would be as an in-between stage for developing an actual orbit-capable airplane. The need to launch the plane with a rocket kinda negates the benefit of that, but this would be more of a concept testing for the engine, with "making it practical to use" left as work for other people.

Re:13,000mph?

[Bob the Super Hamste]

I thought the shuttle's orbital velocity was about mach 25 or so it wouldn't even be half-again.

Re:13,000mph?

[Anonymous Coward]

[[wow. half-again and you're in orbit.

where do you need to go that fast?]]

Um, orbit?

Re:13,000mph?

[Ogive17]

I'd imagine the technology would be transfered to missles.. at that speed do you even need explosives?

But for commercial use, if you can get materials that can withstand mach 20 I'm sure someone will be able to create a commercial airline that can economically go mach 3 or 4.

Re:13,000mph?

[FatAlb3rt]

+/-17500 mph is orbital velocity, mach tends to lose its meaning as it is dependent on air density if memory serves.

Re:13,000mph?

[MozeeToby]

where do you need to go that fast?

How about orbit? Release your payload at the peak of a maximum speed parabola with a relatively tiny rocket motor attached and you can put small satellites into any orbit you want with very little warning. I suspect there are several groups inside and out of the intelligence agencies who would be very interested in getting an orbital view of a situation with just a few hours lead in time.

Or how about just dropping guided tungsten rods as a precision munition. At 13000MPH you wouldn't even need an explosive payload, just let kinetic energy do it's thing. Not quite as powerful as "rods from the gods" but within easy reach once you get a plane up to those speeds.

Re:13,000mph?

[TemporalBeing]

where do you need to go that fast?

Surveillance.

The SR-71 and its kin where great during the Cold War simply b/c they could be nearly any where in the world with little time and highly unplanned - meaning, the Soviets couldn't strategically cover their nukes to keep the SR-71 from seeing them - not enough time between knowing when the plane took off, where it was going, and when it got there to do anything about it. This is just the next step in that evolution - and you cut down the time dramatically...

For instance - launch the vehicle to near-orbit, speed it to site within an hour, spew out a bunch of drones that could then carpet the area - or even surveillance kinetic weapons that drop in fast, send back all kinds of photography, and dead drop a target at the same time.

Re:13,000mph?

[Baloroth]

According to Wikipedia, LEO is actually ~7-8 km/s. This goes 13. So, this thing IS at orbital speeds.

Problem is likely height, since the engines likely require air. And, of course, it's starting at high altitude already using a rocket. Most theoretical ground-orbit planes use multiple engines, since many high-speed engines require you to be supersonic already. Still, this tech could potentially give us much cheaper ground-to-orbit methods.

Also, as to where (besides orbit, and since this is DARPA): it's probably for spy planes. Being able to reach anyplace on earth in an hour or two with higher resolution and longer loiter times than any satellite is a huge advantage. The SR-71 was built for precisely that (but was rather expensive and not quite worth it). Not to mention with that kind of speed no missile created can touch you (the SR-71 standard missile evasion tactic was to simply increase speed, and this is 3-4 times faster).

Re:13,000mph?

[kimvette]

where do you need to go that fast?

The more obvious question is: why not go somewhere that fast?

Have you ever been in a car at over 200mph? I have (I was the passenger not the driver) and it's an absolute blast; you're traveling a football field's length per second at that speed and it's amazing. I've driven a measly 185mph several times and even that is fantastic even out west where all you see is cornfields and sand and rocks, and mountains in the distance. It's a damned shame we don't have an autobahn-like road system. Our (rural) highways were designed for those speeds from the beginning but thanks to incompetence and political greed we need to lower driving requirements to the lowest common denominator (our driving tests consist of driving around a block), and also enhance revenue through unreasonable 55mph-70mph limits on most rural highways. The "unlimited by day" and/or "reasonable and prudent" speed "limits" in Montana and Arizona are history now. :-(

It's not just a matter of fun either, but convenience. Why should it take two or three days to drive cross country, when if traveling at high speed on limited-access highways one could conceivably travel from the East Coast to West Coast in just over 10 hours - about the same time that the inconvenience of air flight takes when you factor in check-in, the federally-mandated pornographic photo shoot or sexual molestation, retrieving your luggage, then getting your rental car, and so on.

Now when it comes to flying, if you could travel across the country at 13,000 mph, you could be on the opposite coast in 10 minutes (or from New York to London in 16 and a half minutes) - so you could conceivably check in (get there an hour or two early) and if all you bring is carry-on (because your business will be completed in time to catch the 10-minute flight home before dinner!) like a laptop, you won't even have to retrieve luggage. Be across the country two and a half hours after booking your flight, go to your meeting (or thanksgiving dinner, or whatever) then be home just a few hours later. Time is precious and is the one commodity you can never get back, so why waste more time than you have to?

Re:13,000mph?

[sleepy_weasel]

How do you think ACME get their products to Wile E. Coyote...?

Re:13,000mph?

[Anonymous Coward]

According to Wikipedia, LEO is actually ~7-8 km/s. This goes 13. So, this thing IS at orbital speeds.

You work at NASA?

Re:13,000mph?

[Anonymous Coward]

7-8 km/s != 13,000mph... Not reaching orbital velocity by itself.

Re:13,000mph?

[Anonymous Coward]

It doesn't because things enter orbit with a given velocity and a given altitude. It must reach orbital speed WHEN it's at leo altitude (about 200kms above the surface).

Re:13,000mph?

[Baloroth]

You work at NASA?

No, but I want to :)

For some reason I assumed the 13,000 was m/s. It's actually ~3.6 miles/sec, or ~5.76 km/s. So, pretty close anyways.

Re:13,000mph?

[kryliss]

And don't forget the ticket price of around $8,000 for a seat on the Concord. Imagine how much seats would cost on a Mach 20 jet liner.

Re:13,000mph?

[Skarecrow77]

Best answer so far.

Re:13,000mph?

[2names]

Wrong, wrong, wrong. *Everyone* knows Mach 1 is the speed of sound in a vacuum. Sheesh, some people.

Re:13,000mph?

[WindBourne]

This will not do mach 3-4 economically. It is around mach 5 that it kicks in. Mach 1-4 is supersonic. Falcon is to test hyper and high hypersonic speeds.

Re:13,000mph?

[GooberToo]

I'd imagine the technology would be transfered to missles.. at that speed do you even need explosives?

Depends on the target. For slow moving objects like people, tanks, buildings, and so on, no explosives needed. For objects like planes, probably so unless they can score a hit with > 90% confidence or so; which is a pretty tall order for something moving that fast. Though maybe not. If the target doesn't know its coming and/or even if it does, how fast can the target evade when a missile is headed your way at mach 20+.

Re:13,000mph?

[SomeKDEUser]

Mach 1 is the speed of sound. Now, I'm at loss to decide what that is in vacuum...

It is relevant to flight in an atmosphere, because it predicts the formation of a shockwave at the surfaces of the aircraft which pass that value -- and this has consequences in terms of structural loading.

It stays relevant after because as the aircraft further accelerates, the angle of the shockwave reduces until it touches the craft. At this point, the shockwave becomes unstable, and a new one is formed _detached_ from the aircraft (at some distance from the nose). The flight is then called hypersonic.

But I never understood the meaning of "Mach" outside the atmosphere. I would guess that you pick the last relevant speed (still within the atmosphere) as the baseline and use that as a unit.

Re:13,000mph?

[vlm]

And don't forget the ticket price of around $8,000 for a seat on the Concord. Imagine how much seats would cost on a Mach 20 jet liner.

Might not be relevant to the problem space. Current economic goal is to destroy the middle classes at all costs. The lower classes won't care, because they'll never fly on an airplane anyway, subsonic, hypersonic, whatever. The only other social group left, will be the super rich who don't care about costs. The key is, can you build, maintain, and fill a hypersonic jetliner with passengers under those social / economic conditions? Probably not. In current similar 3rd world areas they're lucky if the subsonic bizjets don't crash too often, and they rely entirely on 1st world repair and maint infrastructure that probably wouldn't be around. I'm thinking... not going to be applicable.

Maybe the worlds most expensive troop transport?

Re:13,000mph?

[Richard_at_work]

The SR-71 never conducted even a single overflight of the USSR, as overflights were banned after the U-2 shoot down. The Blackbird was relegated to China, North Korea and other theaters, but it never conducted a mission in Soviet airspace.

Re:13,000mph?

[WindBourne]

also missiles. The ability to launch something and run it up to mach 25, while other crafts are moving at mach 1-2 means that it can take out launchers, etc before systems can respond. The only real answer to that will be a laser. At this time, that would be China, Russia, and the west.

Re:13,000mph?

[elrous0]

Because they want to fly low over a city, blow the hell out of everyone's eardrums and windows, and prove once-and-for-all that the Flash would make a really shitty superhero in real life.

Re:13,000mph?

[Anonymous Coward]

The Blackbird was relegated to China, North Korea and other theaters, but it never conducted a mission in Soviet airspace that anyone will ever admit.

Fixed that for you.

Re:13,000mph?

[Anonymous Coward]

But I never understood the meaning of "Mach" outside the atmosphere. I would guess that you pick the last relevant speed (still within the atmosphere) as the baseline and use that as a unit.

True, but it's no better than saying "mph" instead of "m/s," since metric is the only system that really matters.

Re:13,000mph?

[Anonymous Coward]

That we know of. Give it another century and declassified files may change that.

Re:13,000mph?

[Dr. Spork]

It's a part of the space plane project. The future of war (and hopefully lots of peaceful activities as well) is space, and DARPA wants a cheap and reliable way of getting things there. The space shuttle sucked ass. This is a test of an engine that's intended to propel a space plane to near-escape velocity while using an air-breathing engine. If it works, it will be a revolution. By mass, most of the fuel in the main space shuttle fuel tank was oxygen. If you don't need to cart all that weight, imagine all the other stuff you could take up with you!

Re:13,000mph?

[grub]

No, but I want to :)

Dude, this is slashdot. We all want to.... :)

Re:13,000mph?

[amorsen]

Well, if you need to shoot down a satellite, I suppose launching a missile from something that's already going at 13000mph is easier than launching it from the ground.

You wouldn't really need a missile, you could just pick a trajectory which would intersect the satellite, let go of something, and change trajectory. At 13000mph you can actually get quite high on a parabolic orbit.

Re:13,000mph?

[YrWrstNtmr]

It's a damned shame we don't have an autobahn-like road system.

We do. There are really only three differences: The roadbed is built to last a little longer, the road surface is generally built and repaired smoother, and driver skill is generally better. And contrary to popular belief, there are speed limits on much of the German autobahn.

Now when it comes to flying, if you could travel across the country at 13,000 mph, you could be on the opposite coast in 10 minutes (or from New York to London in 16 and a half minutes)

Except for pesky things like g-force and sonic booms.

Re:13,000mph?

[Artifakt]

Mach 1 is normally measured as at sea level, because it is based on the average temperature of air molecules at that same level. When you go high enough, temperature gets significant, as the hotter molecules tend to rise to the top. Speed of sound generally increases with altitude. Pitot tubes and such work with what air they have to measure Mach, and at least until modern computing, that raw data is ALL they gave a pilot, so what they report is normally 'distorted' by both local temperature and by wind-speed. Originally, a Mach meter didn't know how high a plane was at all, and instead reported speed in knots per hour, with a mark on the analog gauge that really only meant, "if you were at sea level, you'd definitely be above the speed of sound now, but what you actually see outside the window may vary", Now-a-days, fancy little boxes in the avionics systems may give a pilot or remote operator adjusted Mach values. A pilot doesn't usually want to know Mach, rather he or she would prefer a few seconds warning when they are about to pass into supersonic and hypersonic regions under local conditions.

Re:13,000mph?

[kimvette]

It was $8.000 then but as efficiency improves and economies of scale work the price will come way down.

Re:13,000mph?

[Anonymous Coward]

Ehmm... Maybe I didn't catch the pratical joke here, but anyways...

Sound needs a medium to travel, ie cannot travel in a vacuum ;-)

Re:13,000mph?

[gstoddart]

Wrong, wrong, wrong. *Everyone* knows Mach 1 is the speed of sound in a vacuum. Sheesh, some people.

I assume you're joking ... because, the speed of sound in a vacuum is precisely zero.

Mach is defined relative to the medium you're in based on the current conditions of that medium.

Re:13,000mph?

[tommy2tone]

Well, if you need to shoot down a satellite, I suppose launching a missile from something that's already going at 13000mph is easier than launching it from the ground.

Why not just put a rocket on top of the something that's travelling 13,000 mph? Keeps the costs down.

but this would be more of a concept testing for the engine, with "making it practical to use" left as work for other people.

This is probably what it is for. Someone probably already has a practical use for it, but doesn't want to reveal what that practical use would be. They just need the engine. DARPA likes to do this, where they say, "Hey design some random crazy piece of equipment that you couldn't ever fathom using. The piece of equipment must be fully functional, and we don't plan on telling you what it is for in the end. Thanks."

Re:13,000mph?

[tommy2tone]

Sound cannot travel in a vacuum. Sound needs molecules to transport sound waves. To determine the speed of sound, you need to know gas properties and temperature. By definition, a vacuum is space with no pressure (i.e. no molecules > molecules each contribute their own pressure, Dalton's Law), therefore no gas.

Re:13,000mph?

[SomeKDEUser]

I always understood Mach to be a local measure: local to the plane, that is -- in fact local to the various surfaces of the plane. Mach as an absolute speed is, as you mention, utterly useless. Pitot tubes, by the way, are used differently to compute speed below or above Mach 1.

Thus the question remains: what the fuck do they mean when they say the shuttle orbits at mach 25? 25 times the speed of sound at the level of the sea in normal conditions? How is that relevant to anything?

Is it one of those "library of congress" measures?

Re:13,000mph?

[countertrolling]

Speed of sound generally increases with altitude.

Back to school for you... Mach is related to air density. Sound moves faster through air that is more dense. I'll let you figure out the rest.

Re:13,000mph?

[SomeKDEUser]

Yes, I know. Thus the question: why do people talk about the space shuttle orbiting the Earth at Mach 25 and no one tells them they are idiots (because they are)?

Re:13,000mph?

[Solandri]

So if we ever invented teleporters or Star Trek-like matter transporters, their only use would be as a weapons delivery system? That's rather short-sighted, don't you think?

Re:13,000mph?

[luis_a_espinal]

wow. half-again and you're in orbit.

where do you need to go that fast?

"When the bomb absolutely has to be anywhere in the world in 30 minutes or less, DARPA is there!"

Where do you need to go that fast? Why do you need microwaves? Why do you need a protocol that allows people to send data over an unreliable network? Why do we need all of this?

Re:13,000mph?

[jamiesan]

Whooosh! KABOOOM!

Re:13,000mph?

[mhajicek]

A dumb kinetic projectile would have a low chance of striking the target, especially if the satellite has avoidance. A high velocity release in the right general direction would be handy, but the ordinance should be able to steer, and it would be best if it also accelerates to diminish avoidance effectiveness and detonates in front of the target to spray the target with many kinetic projectiles.

Re:13,000mph?

[turbidostato]

You didn't.

Re:13,000mph?

[Skarecrow77]

Why do you need microwaves?

I actually bake most of my food in the oven... but you need microwaves because stoufers macaroni and cheese just tastes better when nuked, I can't explain why. Also because you need the radiation to kill most of the more virulent ingredients in hot pockets before you injest them.

Why do you need a protocol that allows people to send data over an unreliable network?

to play world of warcraft, and download porn. sheesh, when was the last time that you saw two strangers (both good looking) having live anal sex in front of you? I can't attest for your life, but it doesn't happen in mine very often, so I need the internet.

Why do we need all of this?

because the alternative is cave painting and I'm pretty sure that we exhausted the entertainment value of that back around the time we bothered to invent geometry so we could build pyramids to screw with the minds of our future descendents.

Re:13,000mph?

[mhajicek]

You want the projectile to detonate before passing the target so that the target gets showered with many high velocity shards. Imagine trying to shoot a ping-pong ball out of the air with a rifle; it's a hard target to hit. Now replace your rifle with a shotgun and it just got a lot easier.

Re:13,000mph?

[turbidostato]

"To determine the speed of sound, you need to know gas properties and temperature."

No, you don't. What you really need are good ears and a chronometer.

Re:13,000mph?

[Anonymous Coward]

lol. See if anyone gets it.

Re:13,000mph?

[craigminah]

While it may be easier to launch a missile from a platform travelling 13000mph, it's many times more difficult getting a platform up to 13000mph. Shooting down satellites from a conventional F-15 using an ASM-135 ASAT missile was first done back in 1985 so no need to increase the complexity (e.g. boost speed to mach 20). I'd imagine the high speeds would be nice for flyovers of enemy airspace for surveillance of some sort. http://en.wikipedia.org/wiki/Anti-satellite_weapon

Re:13,000mph?

[gorzek]

THAT'S THE JOKE. </Wolfcastle>

Re:13,000mph?

[tommy2tone]

good luck with that in the upper reaches of the atmosphere...

Re:13,000mph?

[tommy2tone]

Orbiting at Mach 25 is a fancy (non-scientific) way of saying fast. people go "oooh ahhh" when they hear something like that. And you are right, Mach is a local measure, and the sound speed decreases with altitude (not increasing as suggested by Artifakt). As density drops with altitude, so does the sound speed. That is why the shuttle achieves Mach 25 at the exosphere (re-entry only). Its going pretty fast and there are only a handful of molecules for every cubic meter.

Re:13,000mph?

[Renraku]

Mach is related to air density since it is based on the speed of sound which is affected by air density.

However, I figured a mach-equivalency would have been set up to relate mach to a standard velocity rather than something that is affected by local conditions.

Re:13,000mph?

[2names]

That "whoosh" that you just heard was *not* the Falcon.

Re:13,000mph?

[TrebleMaker]

Because a reasonable person can understand they are comparing the speed of the shuttle in the medium in which it travels (space) with the speed of sound in the medium in which _it_ travels (ie. the atmosphere at ground level). This isn't rocket science.

Re:13,000mph?

[ArcherB]

And don't forget the ticket price of around $8,000 for a seat on the Concord. Imagine how much seats would cost on a Mach 20 jet liner.

Might not be relevant to the problem space. Current economic goal is to destroy the middle classes at all costs. The lower classes won't care, because they'll never fly on an airplane anyway, subsonic, hypersonic, whatever. The only other social group left, will be the super rich who don't care about costs. The key is, can you build, maintain, and fill a hypersonic jetliner with passengers under those social / economic conditions? Probably not. In current similar 3rd world areas they're lucky if the subsonic bizjets don't crash too often, and they rely entirely on 1st world repair and maint infrastructure that probably wouldn't be around. I'm thinking... not going to be applicable.

Maybe the worlds most expensive troop transport?

As much as I want to tell you to keep your paranoid social commentary to yourself, I'm curious:

Who do you think will be flying that hypersonic plane? Will he be "super rich" or "lower class"? I ask because I wonder why anyone would go through the years of training to learn to fly one of these planes just to remain poor. If they will be flown by the super rich, how will the airlines, all staffed with either the super rich or super poor be able to afford to pay and train these guys?

Re:13,000mph?

[SomeKDEUser]

the Mach number is not a speed, it is a dimensionless number. Speeds are units of length / units of time. Dimensionless numbers are useful in fluid mechanics to identify different regimes/transitions between the elliptic/hyperbolic nature of the equations.

The Mach number of the shuttle in space is undefined. Most people don't know the speed of sound anyway...

It is just a fancy way of saying "fast". Unfortunately, it also a lie. One of those lies which leaves people slightly more stupid.

Re:13,000mph?

[serviscope_minor]

Speed of sound generally increases with altitude.

It generally decreases. That is why airliners fly under autopilot in what is known as the coffin corner. It's the corner of the space where they are flying only just below the speed needed to maintain lift and flying only just below the transonic regime where they become unstable.

Re:13,000mph?

[Anonymous Coward]

You could start a bunch of wars, and then build the unemployable PTSD-ridden multiple amputees into the cockpit!

Re:13,000mph?

[Anonymous Coward]

This is a test of an engine that's intended to propel a space plane to near-escape velocity while using an air-breathing engine.

Completely wrong. The HTV-2 is a glider. You might want to read this: http://www.darpa.mil/Our_Work/TTO/Programs/Falcon_HTV-2/Falcon_HTV-2.aspx

Re:13,000mph?

[Anonymous Coward]

This isn't rocket science.

:P

Re:13,000mph?

[Anonymous Coward]

The first stage of a rocket is horribly inefficient. Being able to replace it with an air-breathing jet would reduce the cost per kilogram of cargo put in orbit.

Re:13,000mph?

[nospam007]

"wow. half-again and you're in orbit."

Actually you'd be _out_ of orbit.

Re:13,000mph?

[Anonymous Coward]

Actually, no. Molecules can vibrate in a vaccuum and because fields extend to infinity will interact with each other. Therefore everything you need to establish a longitudinal wave exists. (If you mean a hard vaccuum, no such thing exists. It's forbidden under the 2nd Law of Thermodynamics, which is why Quantum Foam was necessary as a theory. Space, however, is only a partial vaccuum, so the properties of a hard vaccuum are quite unimportant.)

Re:13,000mph?

[Anonymous Coward]

The Earth's atmosphere actually envelops the moon, so there damn well are gas molecules where the space shuttle went. (Hell, even school kids half your age know that NASA lost Skylab to atmospheric drag.)

Re:13,000mph?

[garyebickford]

True. I have seen articles on astronomy discussing sound waves in the interstellar medium, and the speed of sound in the gas around some astronomical object or another. In fact I won a small debate at work over this. :)

Re:13,000mph?

[dbIII]

It's more relevant to flight in a gas medium than relative speed vs a point on the ground, so yes, in a high vacuum it means nothing. If you say "capable of X metres per second" the next question would be "at what altitude/air pressure" so mach speed makes more sense.
Hypersonic air flow is not quite what you'd expect instinctively because of the way shock waves reflect off things. An example most people would recognise is a nozzle - a subsonic nozzle (like a garden hose) reduces in diameter with length to compress the flow while a hypersonic nozzle (like on a Saturn V or the rear of the space shuttle) gets wider with length to compress the flow.

Re:13,000mph?

[BluBrick]

The sound of speed in a vacuum? It's best described as drug-fucked sort of whimper.

Re:13,000mph?

[black soap]

Now imagine using your shotgun to shoot the other player before he can launch the ping-pong ball at you. You might just take out his paddle, or even his hand. If he is lucky. When we are talking about a weapon that could be on the far side of the world in an hour, analogies must be abused.

Re:13,000mph?

[fnj]

Nominate for stupidest "whoosh" yet.

Re:13,000mph?

[CtownNighrider]

He couldn't hear it because he's on a spacewalk. Duh!

Re:13,000mph?

[fnj]

Are you serious? 13,000 mph is not 13 km/s. 13,000 mph is 20,920 km/h, which is 5.8 km/s.

Re:13,000mph?

[perryizgr8]

^^this

Re:13,000mph?

[Yamioni]

Hardly. How the hell do you think the air-breathing jet got there in the first place? And all of the stuff the air breathing jet is going to launch? Yeah, that's right, it all went up on that same rocket. So your initial load up there costs exactly the same as it does now, plus whatever it costs to launch it from the jet. Now suppose you leave the thing up there to serve to fire off more payload into orbit. How do you resupply the thing? That's right, with the same rocket you used to put the jet up there in the first place. If used solely as a launching platform to make it "easier" to get items into orbit, it should actually end up costing more.

The advantage is not and likely never will be cost. The savings is time. As a friendly little goblin once told me: "Time is money friend!" You get to save one or the other, never both.

Re:13,000mph?

[Yamioni]

Correct. Super and Hypersonic techs tend not to scale down to slower speeds at all. This is why you still need conventional tubines on supersonic jets equipped with ram and scramjet engines. They just don't operate at those lower speeds, and if you designed them to, they'd be much less functional at the high speeds (if they even happened to work at all.) It makes much more sense to use multiple engines operating within various ranges than have one engine that does it all.

So I guess you could ask why commercial airliners aren't equipped with ram and scramjet engines. I couldn't tell you for sure, but the most likely answer is that the public isn't well suited to supersonic flight. Grandma's holey 80 year old bones would snap like a twig.

Able to circle the earth in just over 2 hours...

[Zanthor]

That's scooting right along!

Bandwith

[instagib]

Never underestimate the bandwith of 1.000 Blu-ray disks on a Falcon.

Re:Bandwith

[Anonymous Coward]

Comparing this FlyingNet with a coast to coast connection the bandwith is actually not that high:

50 GB * 1000 * 5811.52 meters/second / 4828.032 kilometers = 60 GB/s

A 747 stuffed with hard drives can reach 98 Tbits/s for a similar distance.

"aircraft"?

[circletimessquare]

what's the turning radius? you go around the earth twice before you hit 90 degrees? and after 30 seconds you need to land to get more fuel?

Re:"aircraft"?

[element-o.p.]

When I was working on my pilot's license, a "standard rate turn" was considered a turn at which you traveled 180 degrees per minute*, or 3 degrees per second. 13,000 mph is 216 miles per minute, or 3.6 miles per second. If you plot out your x and y vectors for the track across the ground (i.e., you are assuming that your speed is purely in a plane parallel to the ground, thus neglecting any vertical component of your speed) so that x represents vectors to the left or right of your track before initiating the turn, and y represents the vectors along the direction you were traveling before initiating your turn, then you can approximate how far you travel in the x and y axis for each second with trigonometry. In the first second, you have turned one degree, for an average of 0.5 degree. The y distance vector is 3.6 * cos a (where a is the angle of your turn at any given time), and the x distance vector is 3.6 * sin a, so in the first second, y = 0.03 miles; in the second, y = 0.09 miles, etc. Sum up all of the miles for the first 90 degrees of turn, and you've got a reasonable approximation of the turning radius (~210 miles, if my math is correct). You could get a more accurate figure with calculus, but for a thumbnail estimate, this is probably good enough.

* IIRC, a "standard rate turn" for a jet was a four minute turn, resulting in only 90 degrees per minute, which I believe would double the turning radius calculated above. I suppose it is sufficient to say that at 13,000 mph, the turning radius is "large" :)

Re:"aircraft"?

[circletimessquare]

pilot 2: "we're over new zealand"

-sun rises-

pilot 1: "bearing S51E, to get us over afghanistan"

pilot 2: "but sir, we're over argentina"

pilot 1: "don't worry, you'll see"

-sun sets-

pilot 2: "roger, now over madagascar" ;-)

Re:"aircraft"?

[Anonymous Coward]

Maybe you could do a movie about flying zombies. That would be great.

Re:"aircraft"?

[MokuMokuRyoushi]

But then it would be too easy for them to infect Madagascar!

Long walk

[teaserX]

13,000MPH....blast through the air for about a half hour... Shagging that is gonna be a schlep.

Orbit

[MyLongNickName]

I am not a rocket scientist. i don't play one on TV either. But it seems like there are two separate problems with interplanetary travel. First, you must get to orbit from Earth, then you must get from orbit into a trajectory to get you where you want to go. It seems like our solution has been to create a vehicle to get you from Earth to wherever it is you are going... treating it as one problem.

I see something like this and wonder if this is the future of getting to orbit. Mach 20 is about half of escape velocity, and seems to be in the right range for actually getting into an orbit. Granted, I don't know that I'd want to be a passenger on the Falcon, g forces and all, but the point is that you can specialize... one vehicle is used to get you into orbit (and can focus its functionality). Another vehicle is used to actually do the transport (and can focus its functionality).

I wonder how many years were wasted with the whole "big dumb rocket" mentality...

Re:Orbit

[Anonymous Coward]

It seems like our solution has been to create a vehicle to get you from Earth to wherever it is you are going...

More or less but mostly less. For Moon missions, for example, the spacecraft first enter the Earth orbit, then performs a "Hoffman transfer orbit" (if I recall correctly, it has been a few years) - it enters a orbit that includes both the Moon and Earth - and, lastly, enters the Moon orbit.

Each orbit change includes expending energy therefore you need some amount of fuel. Big rockets work well for this, because the amount of fuel you need to go from the Earth surface to the Earth orbit dwarfs the amount you need to the later orbit transfers.

The biggest problem is that an orbit transfer works between orbits in the same plane. If you need to go from a orbit in a plane to another plane, you need to perform a really expensive maneuver called an orbital plane change (or something like that, I learned this in Russian - although I'm not Russian). You burn a lot of fuel to do this.

This is way "double floor" solutions are bad. If you go using a cheap rocket to a orbiting station and then to other place, you're limited to the same orbital plane of the orbiting station unless you carry with yourself a good amount of fuel: big rockets then enter the equation again, and you're back to square one.

I'm also not a rocket scientist but I played a satellite engineer once in a bad TV show.

Re:Orbit

[Baloroth]

Actually, the "big dumb rocket" mentality exists for a very good reason. While it is certainly (theoretically) possible to build multiple stage launchers, such as strapping a smaller rocket onto a jet plane, the jet then has to be built to take it's own weight+the rocket. I'm not sure if you can build (conventional) jet planes big enough to carry a rocket large enough to reach escape velocity even after being released at high altitudes and speed. Jets only work up to a certain altitude and speed, problems rockets don't have at all. Then there are separation issues of firing rockets on top of a plane. Added complexity should be obvious, but you also get added weight from extra support systems for the different engines.

Rockets, despite the term "rocket science", are actually pretty simple. They scale up well in size, they are pretty reliable, require no air, have no maximum speed (or thrust, for that matter). Hypersonic jets, on the other hand, are very, very complicated. They require certain speeds to function right (turbojets only work if the incoming air is subsonic, for instance, giving them a practical maximum speed. On the other hand, ramjets, IIRC, only work if the incoming air is supersonic, giving them a minimum speed.) Airflow has to be just right, fuel for them is tricky (often extremely dangerous). The SR-71, for example, needed a special, very dangerous, fuel that combusts spontaneously in air to ignite its afterburner. And they incorporate moving parts. Solid fuel rockets don't (at least not in the actual thrust mechanism. Could be wrong about that, though. Small ones don't, I assume larger ones work more or less the same.)

However, I agree that multi-stage engines systems are the future of space travel. They are just quite a bit more tricky than you would think, which is why we don't have them even now.

Re:Orbit

[Anonymous Coward]

Your flaw is that you are not looking at advanced propulsion systems once in orbit. Earth to LEO is a bitch of slug. Once in LEO, you could transfer from your orbital craft to your interplanetary craft and continue from there. Design and optimize each system for their unique requirements. Why should I have to carry the re-entry heat shield all the way to the moon/mars/etc and back, this is not logical.

Chemical rockets and a capsule to LEO is great. Once Apollo was done the next step should have been a foothold in space (station). Then they should have worked on a interplanetary craft with propulsion to exit orbit and go places. Then we would be at the place where we launch people and supplies up to the station with rockets and capsules (like we are going to be doing now). Then we can do work in the station or transfer to the craft and explore our solar system. The shuttle, IMO, was a step in the wrong direction.

Re:Orbit

[Anonymous Coward]

I'm not sure if you can build (conventional) jet planes big enough to carry a rocket large enough to reach escape velocity even after being released at high altitudes and speed.

That's how Pegasus (from Orbital) works, up to 443kg to LEO. It has been around for a while and has put quite a few birds into orbit.

(Same AC who also answered GP)

Re:Orbit

[Anonymous Coward]

The fuel for the SR-71 was designed not to easily combust. The high temperature of supersonic operations was the limiting factor. It did use a chemical starter to ignite the fuel that did spontaneously combust however.

Re:Orbit

[amorsen]

Solid fuel rockets are a bit of a mess. There are a lot of things which can go wrong, and failure tends to be catastrophic. Liquid fuelled rockets are much easier to deal with because you can just turn them off in an emergency. You have to be really really unlucky to get an explosion, especially if you pick a relatively easily handled oxidizer like liquid oxygen.

All you are saving with a ramjet is carrying the oxidizer, with all the downsides you mention.

Re:Orbit

[Baloroth]

Ah, cool, I didn't know about that system. It's still a pretty small rocket, though. I'm guessing something large enough to be man-rated would be a considerably greater technical challenge.

Re:Orbit

[wagnerrp]

The basic concepts of rocket science are fairly simple. Cold gas and low efficiency rockets are even simple in practice, but that is where it ends. There is a great deal of design that goes into solid rockets. You don't just run from one end of the cylinder to the other. The outer casing can't handle the pressure and temperature. You have to burn from the inside out to allow the propellent itself act as an insulator. If you just have a single hole through the center, you will have low thrust at the beginning of the burn, and high thrust at the end. There is a good deal of research into the initial patterns cut into the fuel to maximize the used volume, minimize the unburnt fuel, and fine tune the burn rate over time to control thrust against the decreasing mass and drag.

Liquid rockets are deceptively simple too. A basic rocket simply uses pressure to force fluid into the combustion chamber. You still have to concern yourself with the temperature and pressure sustained in the combustion chamber and nozzle. High performance rockets use ablative materials to protect the structures. Higher performance rockets run fuel and oxidizer through channels beneath those structures to cool them. More still bleed unburned fuel as a protective film. Then you have the fuel pumps. At the flow rates we're talking about, you need tremendous amounts of power. Often times, you have a small combustor run a turbine to run a pump. On larger rockets, you're talking about tens to hundreds of thousands of horsepower in something small enough you could carry around. There are variable geometry nozzles, attitude control, gimbaled engines....

You do realize that all of our current launch systems are multi-stage, right? Each successive stage drops off and jettisons to allow a lighter later stage to achieve higher performance.

Re:Orbit

[wagnerrp]

Don't forget that energy is proportional to velocity squared. Half the velocity of low Earth orbit means only a quarter the energy. Even at Mach 20, there's still a long way to go.

Re:Orbit

[Anonymous Coward]

In fact, human Moon missions did not use Hohmann transfer orbits -- if they had, they would have used the least amount of fuel but would also have taken too much time. They used much faster intersecting but non-tangential orbits and just burned more fuel at Lunar injection to settle into Lunar orbit. Additionally, some missions would change orbits mid-flight, from a Earth free-return orbit to a trans-Lunar trajectory.

Re:Orbit

[wagnerrp]

You are making the mistake that orbital plane changes have any relevance outside the current gravity well. Once you add in a third body, those limitations are gone. Remember that even a polar orbit is pointed in the direction of the lunar orbit twice each time around. You just need to wait until everything lines up. The Cassini has made substantial changes in its orbital plane with just a pittance of fuel, slowly taking advantage of gravitational assist from Saturn's moons.

Re:Orbit

[Anonymous Coward]

Thank you, that's interesting. I'll try to lookup more on Cassini.

Sometimes I wished I hadn't changed my work field, working with satellites was fun. But other things pay better and I must put the kids on a good school. :/

Re:Orbit

[Dr. Spork]

All you are saving with a ramjet is carrying the oxidizer, with all the downsides you mention.

But isn't that like... most of the mass of that dumb rocket on the launchpad? If you could ditch the oxidizer, you could carry a lot more cargo.

Re:Orbit

[tsotha]

I'm not sure if you can build (conventional) jet planes big enough to carry a rocket large enough to reach escape velocity even after being released at high altitudes and speed.

We've been doing it for more than 20 years, and could launch much bigger rockets with a purpose-built carrier.

Jets only work up to a certain altitude and speed, problems rockets don't have at all.

But jets use atmospheric oxygen as an oxidizer, so they're much more efficient. That's the whole reason we're spending money on scramjets at all. Jet engines are more complicated than rocket engines, but as long as you're in the atmosphere the extra complication is a small price to pay for not having to drag around a tank full of LOX.

There are other advantages, too. With a jet carrier you have maneuverability, and can fly to where you'd like to launch the rocket. Launching satellites into geostationary orbit is much more efficient if you can start at the equator. Also, with a jet carrier as your first stage, a first stage abort is no more complicated than turning the jet around and landing without launching the rocket.

Re:Orbit

[jafac]

You're over-stating the simplicity of rockets.

Solid rockets (anyway) - if you're going to put PEOPLE into them, are pretty horrible, because the chunks of propellant tend to burn very unevenly, and cause vibrations. Another drawback is that combustion travels upward along the interior of the rocket body, so that heat and stress of combustion must be accounted for along the entire length of the rocket. The reliability of solid propellant is also not that great - in some cases, pieces of propellant leave the rocket unburned. (this is largely a quality-control issue, however).

In STS, the vibrations required a great deal of structural dampening and reinforcement, which added weight.
The heat of combustion also caused "flare-outs" - which in Challenger, caused a catastrophic loss of vehicle.

In Ares, the vibration required a redesign, such that a huge hydraulic damping system needed to be added to absorb shock to the payload.

Solid boosters also can not be shut-down in case of an emergency (like, if the rocket goes off course), and changes in maximum thrust must be engineered into the engine, and can not be programmed into the flight profile to accommodate mission requirements.

All those criticisms said: solid rockets are absolutely ideal for ballistic missiles.

Now - liquid-fuelled (cryogenic) rockets have their own set of technical problems, but the #1 problem seems to be that you've got to keep a stable of trained and experienced engine-designers staffed and career-ed in order to keep an industry going. This is pretty expensive. And neither private industry, nor government wants to do that. (in the USA). They have no problem paying executives and administrators these kinds of salaries. But apparently aerospace engineers are not allowed to have a career long enough to pay off a mortgage, or send their kids to college.

Re:Orbit

[garyebickford]

Yes. IIRC the fuel pumps for the Space Shuttle push a swimming pool of fuel every second (my mind is saying 250,000 gallons per second, but that may be wrong). And the pumps have to be _very_ smooth, as any variation in the flow or pressure is amplified by the burn, causing extreme oscillations in the vehicle. (There's video somewhere on the net of someone using a propane burner as an audio amplifier - just modulate the propane flow.) As I recall, when they were building the Apollo system, they looked all over the world and did a lot of research, for a pump that had the necessary characteristics. They finally found what they needed in the pumps used for firehoses since the late 1800s! :D

Space plane

[Bob the Super Hamste]

Personally this sounds more like what we should have spent money on instead of the space shuttle since it doesn't seem too far away from being like the old space planes that were being developed. Most of those were rocket assisted and/or dropped from a B52.

Re:Space plane

[__aazsst3756]

Or at least a shuttle replacement. Going back to landing in the ocean just seems so primitive.

Re:Space plane

[lgw]

Primitive means cheap and reliable. And you want to armor as little as your craft as possible against re-entry.

A hyper-sonic aircraft as a non-disposable first stage is interesting, however, precisely because it doesn't have to be armored against re-entry. It's not clear that it would ever be cheaper or safer than a big dumb rocket, but at least it's arguable.

Re:Space plane

[0123456]

A hyper-sonic aircraft as a non-disposable first stage is interesting, however, precisely because it doesn't have to be armored against re-entry.

At Mach 20, your entire flight is 're-entry'.

But more than that, given the MD-21's lousy record of separating drones at merely supersonic speed I'm far from convinced that a hypersonic aircraft carrying a rocket on its back will work very well.

Re:Space plane

[lgw]

You'd need an odd design, like Rutan's White Knight, to make separation at all safe. I think we'll eventually have plasma vane steering for both hypersonic travel and re-entry, allowing us to dispense with the armor (same principle as the cavitation torpedo) and that might change the equation a bit.

Ricky Bobby

[Anonymous Coward]

I wanna go fast.
-www.awkwardengineer.com

How many parsecs?

[Anonymous Coward]

Could this vessel do the Kessel run in?

Re:How many parsecs?

[Revotron]

I have modpoints, but I can't find the "-1, Woosh" rating.

Re:How many parsecs?

[Anonymous Coward]

Everybody knows that the Kessel run is considered to be 23 parsecs, so clearly Han was bragging that he knew a shortcut.

Why DARPA and not NASA?

[schwit1]

Are their any write-ups on the propulsion and heat resistant materials?

Re:Why DARPA and not NASA?

[SirWhoopass]

Why DARPA and not NASA?

DARPA has money. NASA does not.

Re:Why DARPA and not NASA?

[Anonymous Coward]

Are their any write-ups on the propulsion and heat resistant materials?

The propulsion system appears to be gravity. The DARPA site says it's a glider.

http://www.darpa.mil/Our_Work/TTO/Programs/Falcon_HTV-2/Falcon_HTV-2.aspx

Re:Why DARPA and not NASA?

[Thud457]

DARPA also isn't hamstrung by Congress micromanaging every aspect of a 15 year project, dictating using vendors from the chairman's home district and cutting the budget six times in eight years before canning the idea completely.

The military may be the only branch of our government that can successfully do any long-term planning any more.

Re:Why DARPA and not NASA?

[florescent_beige]

Are their any write-ups on the propulsion and heat resistant materials?

It's a glider.

Materials.

Re:Why DARPA and not NASA?

[garyebickford]

A case in point, told me by a relative who worked on the Space Shuttle's navigation computer systems for IBM, back in the 1970s. It seems that in the late 1960s some Navy admiral did a favor for a buddy, and authorized a contract for his company to build a bunch of small computers for some project. They didn't work for the project, and weren't used. A large number of them (all that the Navy had ordered) were put on a shelf somewhere. Later, this admiral moved over to NASA, and in order to save his own face he ordered NASA to use these computers to be used for the nav system, thus turning a pig's ear into apparent gold and making the Navy bean counters happy. Of course, these were 1960s technology and hugely underpowered - IIRC they were 4-bit systems with a cycle time of a few kilohertz. These are the much-vaunted triple-redundant navigation computers that were originally used on the Shuttle. At the time of first launch, the calculators carried by the astronauts were more powerful than the nav computers.

Another computer with a different architecture was also designed and built by another company (Raytheon) and programmed in a different language. This was the fourth nav computer, that checked up on the first three.

I wonder if any of this was ever replaced?

Re:Why DARPA and not NASA?

[dbIII]

I saw a scramjet model very similar to what is apparently being used on Falcon in 1987. It's a bit more than a 15 year project and NASA was paying for most of it back then.

Friday?

[SiChemist]

When do the semi-ballistics start running?

Re:Friday?

[Fnord666]

When do the semi-ballistics start running?

Do mean things that are getting on towards ballistic, or ballistic things that carry tons of cargo?

Around the world

[shdowhawk]

Radius of earth = ~3959 mi

13,000 mph / 3,959 mi = a little over 3 times around earth per hour

In metric: about 20,900 kmh / 6,378 km

Half hour in the air = a little over 1.5 times around earth. Nice! I wonder what the speed up / slow down times are to hit Mach 20.

Re:Around the world

[jandrese]

Obviously they aren't going to be skimming the surface of the earth at 13,000 mph, so it's going to have to travel quite a bit further to make that full circumference.

Re:Around the world

[Monkey-Man2000]

Radius of earth = ~3959 mi

13,000 mph / 3,959 mi = a little over 3 times around earth per hour

In metric: about 20,900 kmh / 6,378 km

Half hour in the air = a little over 1.5 times around earth. Nice! I wonder what the speed up / slow down times are to hit Mach 20.

I think you want to use the circumference of the earth and not radius. Still pretty fast though.

Re:Around the world

[Anonymous Coward]

Radius of earth = ~3959 mi

13,000 mph / 3,959 mi = a little over 3 times around earth per hour

In metric: about 20,900 kmh / 6,378 km

Half hour in the air = a little over 1.5 times around earth. Nice! I wonder what the speed up / slow down times are to hit Mach 20.

Yes the radius is about 3959, but what I think you are thinking of is circumference which is 2pi*r, so more like 1hr 54min to go around the earth.

Re:Around the world

[Anonymous Coward]

LOL... you're kidding, right?

Re:Around the world

[Anonymous Coward]

Unless you're planning on flying through the earth, the circumference (~24,000 miles) is the figure you're interested in. A half hour will get you 1/4 the way around the earth. Still not too shabby.

Re:Around the world

[Anonymous Coward]

Check your math: C=2*pi*r. So, nearly 25000 mi / 40000 km.

Re:Around the world

[lgw]

Here are some hints:

The kilometer was originally 1/40000 of the Earth's circumference, so 40k km is always a handy estimate.

The nautical mile was originally one minute of arc at the equator (or one minute of latitude - either way), so the Earth circumference is 21600 nautical miles. This is also handy - an airplane moving 600 knots is covering 10 degrees per hour. 12000 knots is 200 degrees per hour.

Re:Around the world

[tacokill]

One additional point of note: This works great for latitude but do not apply this same principle to longitude. Longitude is NOT an equal distance as it depends where you are on the earth. If you are near the poles, a degree of longitude is much shorter than a degree of longitude at the equator.

Re:Around the world

[TheClam]

Or you've been math trolled. Imagine how many math Nazis there are here compared to grammar Nazis. This is a whole new level of trolling.

Re:Around the world

[Alioth]

The radius of the earth isn't a good thing to use, well, unless this thing is going to tunnel through the earth from one side to the other via the core at mach 20. You want the circumference, which is 2 * pi * r, in other words, a distance well over 6 times further than you thought...

Re:Around the world

[Monkey-Man2000]

Or you've been math trolled. Imagine how many math Nazis there are here compared to grammar Nazis. This is a whole new level of trolling.

Under normal circumstances (or on 4chan) you'd probably be right, but based on the GP's ID I think he's probably just a 12-year old that hasn't reached solid geometry in high school yet. I was trying to be polite though -- looks like that failed. :(

Aircraft Carries Obsoleted.

[sycodon]

About the time China gets her aircraft carriers built, debugged and they learn how to operate from them and what the hell to do with them, we might have drones that can deliver ordinance anywhere in the world in just a few hours.

The need for a carrier group to project power may well go by the wayside.

Re:Aircraft Carries Obsoleted.

[vlm]

About the time China gets her aircraft carriers built, debugged and they learn how to operate from them and what the hell to do with them, we might have drones that can deliver ordinance anywhere in the world in just a few hours.

The need for a carrier group to project power may well go by the wayside.

Cost per pound of ordnance delivered might still be won by the carrier.

Also you can spool up the assembly lines for ordnance faster than spooling up the lines for more space planes; although carrier assembly lines are even slower...

Re:Aircraft Carries Obsoleted.

[GooberToo]

Projection of power is about what can be seen - not knowing something merely exists.

When a carrier groups parks outside your window, the thought isn't, "So that's what a carrier group looks like." Rather, the message is, "This is a nice reminder to pull your head from ass else we'll do it for you." Or perhaps, "You have our full support. We're here to help." Regardless, physical presence is almost everything in that projection of power.

Re:Aircraft Carries Obsoleted.

[Grygus]

The nuclear arsenal would seem to belie this theory.

Re:Aircraft Carries Obsoleted.

[ColdWetDog]

The nuclear arsenal would seem to belie this theory.

And exactly how many times have carrier groups been nuked compared to the number of times they have been sent out for force projection?

Ultimate Doom is not always the appropriate tactical response....

Re:Aircraft Carries Obsoleted.

[Anonymous Coward]

Carriers and their aircraft can linger.

Re:Aircraft Carries Obsoleted.

[GooberToo]

I don't know if that's a cheeky response or not, but assuming you have any clue about the topic, its seemingly impossible to not read that as a statement of full agreement.

If not, please explain.

Re:Aircraft Carries Obsoleted.

[sycodon]

I believe he/she meant that nuclear missiles can also project power in a matter of hours and that hasn't seemed to impress people.

Pretty good point but of course it's the difference between threatening someone on your lawn with a Maverick missile as opposed to a paintball gun. They will more inclined to believe that you will leave them with painful welts rather than obliterate them with the Maverick.

Re:Aircraft Carries Obsoleted.

[sycodon]

True dat.

Re:Aircraft Carries Obsoleted.

[sycodon]

Wait...are you talking cost effectiveness with regards to the military?

Re:Aircraft Carries Obsoleted.

[jedidiah]

The USSR managed to project force plenty well without having the best Naval air power around.

There's more than one way to skin a tiger.

Re:Aircraft Carries Obsoleted.

[0123456]

Carriers and their aircraft can linger.

Until it's sunk by a hypersonic missile or a submarine, anyway.

Re:Aircraft Carries Obsoleted.

[turbidostato]

But of course yes!
  Maybe you didn't notice but cost effectiveness is the difference between winning wars and losing them.

Re:Aircraft Carries Obsoleted.

[Genda]

At 13,000 mph the delivery time is about half an hour. Figure the furthest spot on the planet is 12,000 miles from launch site and that means less than an hour ro anywhere on the planet. Can you say DAMN FAST!!!

As for delivering ordinance, you would coordinate a fast delivery vehicle with local eyes in the air and possibly eyes on the ground. Drop a couple multi-warhead smart bombs and you pretty much have obsoleted any other kind of bomber. Add fly by wire plus autonomous smart electronics, and predator drones, and you pretty much don't have to change out of your jammies to blast the snot out of somebody half a world away.

On the more productive side, this technology would lend itself to eventually creating aircraft capable of LEO space flight, and ultra high speed global travel. The idea of getting anyplace on earth in less time than it takes to get through the security line is kind of shocking. Anyone for high tea in Johannesburg?

Re:Aircraft Carries Obsoleted.

[cavreader]

The major country nuclear arsenals are pretty much useless in any strategic sense because one ICBM launch will trigger thousands going in all directions leaving nothing left to argue about. The only real purpose they serve is preventing this type of total global annihilation. Orbital based kinetic weapons are the next phase of weapon development. Non-explosive projectiles targeted from orbit are capable of the same amount of destruction as a nuke without the nasty radioactive after taste. Accuracy might not be as good as modern GPS based missiles but then again it isn't necessary to hit a specific chimney or window with a weapon of this power.

Re:Aircraft Carries Obsoleted.

[rubycodez]

the business model is to engage in prolonged wars without plan or purpose, to line defense contractor pockets and provide patriotic fodder for politicians to feed the masses.

Re:Aircraft Carries Obsoleted.

[rubycodez]

nope, didn't notice with all these expensive unwon "authorized actions" we've been farting around with since WW II

Re:Aircraft Carries Obsoleted.

[Renraku]

I doubt it..a hypersonic cruise missile that costs a few million taking out a carrier that costs a lot more than that with planes that cost a few million each and trained crewmen that aren't that cheap either... Also you have to factor in the damage that ship would have done had it been left alone..

Re:Aircraft Carries Obsoleted.

[Renraku]

But you realize, of course, that ICBMs are easily detectable in the boost phase. There are satellites from many countries with hardware and software to detect them. What if you could launch something that had the same capacity and accuracy as an ICBM without the big boost phase? Maybe you have one of these that flies relatively low and really fucking fast..then it can convert into a cruise missile for the last little bit of its lifespan and blow the hell out of someone's city.

Imagine if it were stealthy and undetected. Oops, looks like there goes Pyongyang..guess America should go set up a humanitarian station...

Re:Aircraft Carries Obsoleted.

[Anonymous Coward]

Projection of power is about what can be seen - not knowing something merely exists.

As we haven't used a nuclear weapon against an enemy in more than 60 years, you would seem to think that people don't sufficently fear our doomsday capacity.

Re:Aircraft Carries Obsoleted.

[tyrione]

I doubt it..a hypersonic cruise missile that costs a few million taking out a carrier that costs a lot more than that with planes that cost a few million each and trained crewmen that aren't that cheap either... Also you have to factor in the damage that ship would have done had it been left alone..

What jet fighter costs a few million each? I agree with your point that the missile is more cost effective, but you're being too conservative with respect to the cost of the Carrier and it's total cost per deployment.

Re:Aircraft Carries Obsoleted.

[Martin Blank]

It doesn't need to fly low. It can basically cross half the globe in a little over an hour. Even with a long-lead tracking system, your air defense with its range of perhaps 200km has a span of about 55 seconds in which to intercept it, which in the scheme of things makes it very difficult. It's not going to be maneuverable, but you have to have both timing to intercept and timing to explode before the inbound arrives so that you catch it in the blast. Alternately, you can try a direct intercept, but that's even more difficult.

Re:Aircraft Carries Obsoleted.

[Intrepid imaginaut]

The F-22 Raptor costs $150 million a pop.

Re:Aircraft Carries Obsoleted.

[cavreader]

The main problem with nuclear weapons is the damage to the ecosystem. Just look how the world freaked out with Japan's nuclear reactor failures. Any nuclear attacks, even on countries with no ability to retaliate would scare the shit out of every country on the planet and create massive unrest and uncertainty. The only real benefit of a nuclear arsenal is to prevent the takeover of your country by a foreign power if you lose a conventional war. Sort of like the mindset "If I can't have it nobody can have it". That is why the Arab countries have abandoned conventional military attacks against Israel and changed tactics to use the Palestinians as their weapon of choice. It's very unlikely that even a massed Arab attack on Israel would succeed any better than their previous attempts but if Israel thought they were losing they would make sure that every Arab country participating in the attack would be left with radioactive craters where their major cities are located.

Re:Aircraft Carries Obsoleted.

[Anonymous Coward]

Unless the carrier gets taken out by a 13000mph cruise missile before it can deliver that ordnance. I know carriers are ridiculously big, and designed to function with various holes blown in them, but I can't imagine the destruction something that fast causes -- it has to be at least a serious threat.

Re:Aircraft Carries Obsoleted.

[ae1294]

They will more inclined to believe that you will leave them with painful welts rather than obliterate them with the Maverick.

Well maybe I got the Maverick for free and need the garage space...

Re:Aircraft Carries Obsoleted.

[Anonymous Coward]

Nukes are cost effective. Have we considered nukes?

Re:Aircraft Carries Obsoleted.

[GooberToo]

Nuclear missiles don't project power. They are a deterrent and a projection of death.

People don't fear launch of nuclear missiles from the US. They do, however, fear the arrival of a US carrier group off their shores.

Re:Aircraft Carries Obsoleted.

[rubycodez]

No they are not, the total cost of the U.S. nuclear program from 1960 to 1996 was a whopping 30% of the military budget. That was an estimated 5.5 trillion dollars minimum. Not cost effective at all, and just consider the trillions more of cost of actually using them (even a one-sided nuclear war is hell on your stock portfolio, trust me) http://www.nti.org/e_research/e3_atomic_audit.html

Re:Aircraft Carries Obsoleted.

[Yamioni]

Projection of power is about what can be seen - not knowing something merely exists.

That 'God' fellow must be one bad-ass mofo then. Millions of Christians are convinced he exists even though they've never seen him, and still follow his word.

Though in commonplace I agree with with you completely. You have to show your power in order to make people fear/respect/acknowledge it.

Who needs NASA?

[Animats]

Between DARPA and Space-X, we may get space travel back.

One of the better ideas in spacecraft was the Boeing/USAF X-20 Dyna-Soar., from 1957 to 1963. This was a small aerodynamic craft to be launched atop a booster and land on a runway like an airplane. It was the next step after the successful X-15. The project was cancelled in favor of the Gemini spacecraft. This DARPA project is a lot like the old Dyna-Soar.

Re:Who needs NASA?

[catmistake]

This DARPA project is a lot like the old Dyna-Soar

One might even call it... Dyna-Soar Jr.

Re:Who needs NASA?

[jafac]

X-33 was the inheritor of those ideas. Canceled by congress in 1996. Yes - there were serious technical issues - but the concept, as a whole, was nowhere nearly as flawed as STS. It was quite elegant. I do not understand why there was no discussion of continuing this research when STS was canceled. Oh - yes I do: There could be no pork for a certain congressional district in Utah, if we used a sensible design.

Re:Who needs NASA?

[dpilot]

There used to be a pair of webcams showing the X33 build floor, and I used to track the progress. Usually rather glacial, but sometimes things moved along quite quickly. Separately there was a fair amount of information available about the aerospike engine and its testing. From what I remember, the delamination failure of the fuel tanks during testing did it in.

Thinking of pork or at least Congressional interference in the space program, I seem to remember hearing that *someone* actually wrote into NASA funding legislation that they would not be permitted to even THINK about the TransHAB module. Any idea who hated it so badly or why? I can only guess that the solid-body HAB module was slated to come from their district. Of course in typical irony, I don't believe the solid-body HAB module has ever gotten off the ground, while the TransHAB was bought out by Bigelow, and there are 2 reduced-scale versions on orbit.

Not an Aircraft - more like a MARV

[wisebabo]

It's an unpowered lifting body, no engines, so it basically glides (at a very high speed!) and is capable of surviving re-entry.

It looks like it's a weapons delivery system capable of avoiding terminal ballistic missile defenses. A MARV (MAneuverable Reentry Vehicle).

I thought we (the U.S.) were the only ones with a (semi)-robust missile defense system (well I guess the Isrealis also). I guess DARPA's just planning ahead for the day when the Chinese decide to redress the strategic balance by spending their Trillions on a good BMD. Also I'm thinking it must be so expensive that the only kind of warhead that's worth placing on board is nuclear. But then again maybe there are VERY specific soft targets which you absolutely positively have to kill in an hour (because that's all you know they'll be in that location for). Then a "conventional" warhead could do (or at 13,000MPH just a bunch of tungsten rods "Rods from God" would do. Think of it as an intercontinental sniper rifle with bullets that can swerve around defenses. Good for "decapitating" an enemy, (I guess a lot of threats we face would go away if we could take out just the top few people/person: are you listening Kim Jong-Il? Qaddafi? S&P ratings board?).

I was kinda hoping DARPA was working on a (much) faster version of the Wave-rider hypersonic aircraft. Oh well, guess even they can't beat the laws of physics (and our lack of a good propulsion system).

Even "cooler" would be a laser that could be quickly lofted into space and would zap a target on the earth below. Unfortunately, "Real Genius" notwithstanding we don't have any lasers compact enough to be launched in anything short of a Saturn V (I don't think Dr. Teller's nuke pumped X-Ray laser was ever shown to work). That pesky outer space treaty prohibits us from placing weapons in space so we can't just have laser satellites floating around picking off people we don't like I guess.

Re:Not an Aircraft - more like a MARV

[Dr. Spork]

FTA:

[A]n Air Force Minotaur IV rocket which delivers the Falcon to a starting point high in the atmosphere where its engine ignites and if all goes well it will blast through the air for about a half hour, DARPA says.

Did you notice the thing about how it does have an engine? This is not a balistics test. It's a test of what I assume is a fairly mature version of the scamjet, though I wish TFA would have used that word if it indeed is a scramjet engine. But unambiguously, it's some kind of engine that's presumably not a rocket.

Re:Not an Aircraft - more like a MARV

[Anonymous Coward]

The article is wrong, Falcon is a glider that rides a rocket. Read the darpa.mil link in the article.

Re:Not an Aircraft - more like a MARV

[Anonymous Coward]

Did you notice the thing about how it does have an engine?

Follow the link to the DARPA site. DARPA says it does not have one. The article linked by the OP got it wrong.

Odds are this link is going to be more accurate.

Re:Not an Aircraft - more like a MARV

[jittles]

It's a test of what I assume is a fairly mature version of the scamjet...

woah is Bernie Madoff working for DARPA now?

Re:Not an Aircraft - more like a MARV

[castarritt]

The Falcon vehicle is just a glider. There might be a second stage rocket that ignites after separation from the Minotaur IV rocket, but there is nothing exotic like a scramjet. What they are testing is the ability of the Falcon vehicle to glide and maneuver unpowered at high-hypersonic speed.

Re:Not an Aircraft - more like a MARV

[DeadCatX2]

That sounds a lot like a scramjet. It needs something to launch it fast, but once it gets going it flies itself. wikipedia on scramjet only shows it going up to Mach 10 but I imagine it goes farther.

Re:Not an Aircraft - more like a MARV

[Dr. Spork]

Yup, you guys are right. It really is a glider! Stupid me for RTFAing (and not following up). But I still hope that a part of the point of this research is to help design the space plane with a scramjet engine.

Re:Not an Aircraft - more like a MARV

[Immerial]

Yup, reminds me of the short Whistle (2002). From Duncan Jones- the same guy you directed Moon and Source Code. Saw it as an interesting extra on the Moon DVD.

Re:Not an Aircraft - more like a MARV

[Anonymous Coward]

Falcon airframe
Waveriders (you want to look at Viscous Waveriders, or maybe Osculating Cone)

It looks closest (IMHO) to the Min CD variant of the Viscous Waveriders, but that is rated on the website at only Mach 14. The Mach 25 waverider design doesn't have the upturns at the back. The osculating cones method is also given at only Mach 6.

As for the uses, the aerospaceweb site also has some examples of potential use. It suggests that airframes designed for cruising at mach 20 may well be used for single-stage-to-orbit applications. I still think the vehicle is more likely to be used as a launchpad for a rocket, since it's reusable (as per White Knight) and likely to be much cheaper than either the shuttle's boosters or a conventional first stage.

Re:Not an Aircraft - more like a MARV

[Anonymous Coward]

13,000 MPH
13,000 / 60 = 216.6666 miles/min
216.6666 / 60 = 3.6111111 miles/sec

Wow, that's fast....

Re:Not an Aircraft - more like a MARV

[fnj]

Err, that's not what TFA says. "[A] Minotaur IV rocket ... delivers the Falcon to a starting point high in the atmosphere where its engine ignites and if all goes well it will blast through the air for about a half hour." Sounds powered to me.

Re:Yay

[atrain728]

What kind of food are you eating for $5000 / day?

For an hour??!

[dimethylxanthine]

I though it took the Shuttle 20 minutes to reach LEO...?

Re:Yay

[NatasRevol]

The kind developed by DARPA??

Re:Yay

[riverat1]

If you paid $5000 in federal taxes then you're not budgeting very well if you can't afford food.

Carriers vs missiles

[rlglende]

I think missiles will win. The US, in its own self-interest, should sell its entire Navy to the Chinese, retire a few $T in national debt.

By the time they learned to use it effectively, it would be obsolete.

I feel the need...

[Anonymous Coward]

....the need... ...for speed!

Who needs weapons for something going Mach 20? Just the shockwave of a low flying craft like that would ruin most anyone's day. Can you imagine the results of 5-10 such aircraft's shockwaves interacting if they flew in formation? Some spots would be less intense but others even more so. Owch.

And, yes, the Shuttle was getting pretty old. It was designed and built decades ago. Newer, stronger, lighter, and more powerful designs NOT affected by political committee should be able to lift more and with better safety for pilots. Heck, you could probably coat heat resistant tiles with layers of artificial diamond over vacuum spaced lattices of carbon nanotubes or some such if it is better than ceramic. What held the old shuttles together and can we make it a magnitude stronger now?

Re:I feel the need...

[garyebickford]

Diamond is not a good idea in this application. Carbon burns in the presence of Oxygen with an ignition temperature of (IIRC) about 500C (ah, here's a ref: 870-1170K - I guess that's 600C+). If kept away from anything to combine with it, diamond can handle much higher temperatures, but that doesn't apply here.

Oh the irony...

[Anonymous Coward]

of a military pedant who apparently believes government agencies only do what they say they do?! The grammar nazi who misspells has nothing on you...

Re:Oh the irony...

[Richard_at_work]

To all three of you who replied with essentially the same comment - "that we know of"...

I can find detailed information on basically any SR-71 and U-2 deployment in public records, including the Taiwanese exchange program in both aircraft (the U-2 exchange was a mild success, the SR-71 was cancelled very very quickly when it turned out that the Taiwanese pilots didn't have the aptitude to fly the aircraft).

I can find plenty of reports on "skirting" flights, where the SR-71 flew at operation altitude on the edge of Soviet airspace, "seeing" several hundred miles into their territory.

I can see a lot of information on missions that were denied at the time, but now released, like the SR-71s involvement in the 1980s Libya campaign.

But I have not once come across a hint of any U-2 or SR-71 activity over the Soviet Union after the ban on overflights.

Want to know why? Because they never happened. And for two very very good reasons.

Firstly, satellite camera technology improved massively during the 1960s and 1970s - for strategic information, you didn't need the abilities of the U-2 or the SR-71.

Secondly, the US had already been shown up on the public stage with their U-2 overflights - they are illegal and can be construed as an act of war. The USSR knew they had been happening, they just couldn't prove it to the world until they shot down Gary Powers. And yes, the USSR was improving its SAM capabilities every year (they were already ahead of the US), it was just a matter of time before the SR-71 became vulnerable so why risk it?

So, no hints of any SR-71 overflights taking place - not even in the ramblings of past SR-71 and A-12 pilots - and no reason for the overflights to take place. Simply put, they didn't happen.

User review

[Anonymous Coward]

Pros: Quick. Convenient.
Cons: No bathroom. Cramped seating. $2.5 million charge for each additional piece of luggage. Two-year security check.
Would fly on again.

Flight of the Navigator?

[mj1856]

Holy crap - you mean Disney got it right?
Flight of the Navigator spaceship
Darpa Falcon

Re:Flight of the Navigator?

[bobaferret]

mod this up funny! or no one is old enough to remember that movie.

They told it like it is

[GPS Pilot]

a lot of threats we face would go away if we could take out just the top few people: are you listening S&P ratings board?

Wow, you don't grok the phrase "don't shoot the messenger," do you?

Nope, try $300+ million/aircraft as of 2006,

[ridgecritter]

given the $62 billion program cost to yield 181 airframes. Followon unit costs were estimated at about $70 million. Whether those estimates are credible, who knows?

http://en.wikipedia.org/wiki/Lockheed_Martin_F-22_Raptor

But it's a beautiful airplane, I'll grant you that. Saw it at an airshow in Sacramento. Incredible engineering.

Re:Nope, try $300+ million/aircraft as of 2006,

[black soap]

I saw them being built. The precision was insane. 3 days to cool the frame to a specific temperature so dimensions were exact.

If you dig deep into the article

[wisebabo]

Sorry but if you dig deep into the article (and even look into DARPA's slides and animations) you'll see it doesnt have any engines except for four small RCS (reaction control thrusters) on the rear (you'll need to view the animations). The mission profile also shows this with the only course/speed changes coming from the aero surfaces and thrusters. As much as I'd like to believe that DARPA's leapfrogged the current state of the art, there is no propulsion system (and certainly not scramjet/ramjet, no air intakes or external combustion surfaces like NASA's waverider.)

Too bad.

Sorry just RCS

[wisebabo]

Sorry but if you dig deep into the article (and even look into DARPA's slides and animations) you'll see it doesnt have any engines except for four small RCS (reaction control thrusters) on the rear (you'll need to view the animations). The mission profile also shows this with the only course/speed changes coming from the aero surfaces and thrusters. As much as I'd like to believe that DARPA's leapfrogged the current state of the art, there is no propulsion system (and certainly not scramjet/ramjet, no air intakes or external combustion surfaces like NASA's waverider.)

Anybody think of SpaceX?

[CtownNighrider]

When I saw the headline I immediately thought it had to do with the Falcon line of SpaceX rockets.

Re:Big Dumb Rockets

[Anonymous Coward]

No, he's asking why we aren't using a tug out of the atmosphere, instead of launching the entire stack on one rocket from the ground. The reason why we don't launch the fuel in 4 tonne chunks on a SSTO (DC-Y) or a TSTO (Kistler K-1) is that it wouldn't pay for a politically necessary jobs program. These vehicles would be cheap to develop (comparatively) and use no labour to operate. Hence no interest in Washington.

A Big Dumb Rocket on the other hand would "create" $100B worth of jobs over 15 years.