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DARPA Set To Blast Falcon Mach 20 Test Flight

CmdrTaco posted more than 3 years ago | from the are-we-there-yet dept.

The Military 201

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."

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13,000mph? (2)

Skarecrow77 (1714214) | more than 3 years ago | (#37034194)

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? (1)

HappyHead (11389) | more than 3 years ago | (#37034278)

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.

Aircraft Carries Obsoleted. (2)

sycodon (149926) | more than 3 years ago | (#37034764)

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. (1)

vlm (69642) | more than 3 years ago | (#37034890)

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. (2)

sycodon (149926) | more than 3 years ago | (#37035308)

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

Re:Aircraft Carries Obsoleted. (2)

GooberToo (74388) | more than 3 years ago | (#37034950)

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. (2)

Grygus (1143095) | more than 3 years ago | (#37035036)

The nuclear arsenal would seem to belie this theory.

Re:Aircraft Carries Obsoleted. (1)

ColdWetDog (752185) | more than 3 years ago | (#37035102)

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. (1)

sycodon (149926) | more than 3 years ago | (#37035272)

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. (1)

jedidiah (1196) | more than 3 years ago | (#37035354)

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. (1)

GooberToo (74388) | more than 3 years ago | (#37035190)

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. (1)

sycodon (149926) | more than 3 years ago | (#37035294)

True dat.

Re:Aircraft Carries Obsoleted. (0)

Anonymous Coward | more than 3 years ago | (#37035178)

Carriers and their aircraft can linger.

Re:Aircraft Carries Obsoleted. (2)

0123456 (636235) | more than 3 years ago | (#37035558)

Carriers and their aircraft can linger.

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

Re:13,000mph? (2)

amorsen (7485) | more than 3 years ago | (#37035252)

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? (3, Insightful)

tommy2tone (2357022) | more than 3 years ago | (#37035390)

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? (1)

Bob the Super Hamste (1152367) | more than 3 years ago | (#37034290)

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

Re:13,000mph? (1)

FatAlb3rt (533682) | more than 3 years ago | (#37034436)

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

Re:13,000mph? (4, Funny)

2names (531755) | more than 3 years ago | (#37034820)

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

Re:13,000mph? (0)

Anonymous Coward | more than 3 years ago | (#37035338)

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? (2)

gstoddart (321705) | more than 3 years ago | (#37035384)

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 [wikipedia.org] is defined relative to the medium you're in based on the current conditions of that medium.

Re:13,000mph? (1)

SomeKDEUser (1243392) | more than 3 years ago | (#37034942)

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? (0)

Anonymous Coward | more than 3 years ago | (#37035202)

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? (1, Informative)

Artifakt (700173) | more than 3 years ago | (#37035266)

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? (0)

SomeKDEUser (1243392) | more than 3 years ago | (#37035418)

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? (0)

countertrolling (1585477) | more than 3 years ago | (#37035432)

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? (1)

tommy2tone (2357022) | more than 3 years ago | (#37035410)

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? (1)

SomeKDEUser (1243392) | more than 3 years ago | (#37035470)

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? (1)

jamiesan (715069) | more than 3 years ago | (#37035614)

Whooosh! KABOOOM!

Re:13,000mph? (1)

Anonymous Coward | more than 3 years ago | (#37034298)

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

where do you need to go that fast?]]

Um, orbit?

Re:13,000mph? (1)

Ogive17 (691899) | more than 3 years ago | (#37034402)

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? (1)

WindBourne (631190) | more than 3 years ago | (#37034854)

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? (1)

GooberToo (74388) | more than 3 years ago | (#37034892)

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? (1)

MozeeToby (1163751) | more than 3 years ago | (#37034456)

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? (1)

TemporalBeing (803363) | more than 3 years ago | (#37034472)

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? (1)

Richard_at_work (517087) | more than 3 years ago | (#37034976)

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? (0)

Anonymous Coward | more than 3 years ago | (#37035104)

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? (0)

Anonymous Coward | more than 3 years ago | (#37035206)

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

Re:13,000mph? (1)

WindBourne (631190) | more than 3 years ago | (#37035000)

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? (1)

Baloroth (2370816) | more than 3 years ago | (#37034486)

According to Wikipedia [wikimedia.org] , 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? (0)

Anonymous Coward | more than 3 years ago | (#37034612)

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

You work at NASA?

Re:13,000mph? (1)

Baloroth (2370816) | more than 3 years ago | (#37034772)

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? (1)

grub (11606) | more than 3 years ago | (#37035216)


No, but I want to :)

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

Re:13,000mph? (0)

Anonymous Coward | more than 3 years ago | (#37034654)

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

Re:13,000mph? (0)

Anonymous Coward | more than 3 years ago | (#37034678)

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? (1)

kimvette (919543) | more than 3 years ago | (#37034538)

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? (1)

kryliss (72493) | more than 3 years ago | (#37034774)

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? (1)

vlm (69642) | more than 3 years ago | (#37034960)

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? (1)

kimvette (919543) | more than 3 years ago | (#37035288)

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

Re:13,000mph? (1)

YrWrstNtmr (564987) | more than 3 years ago | (#37035264)

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? (1)

sleepy_weasel (839947) | more than 3 years ago | (#37034554)

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

Re:13,000mph? (1)

Skarecrow77 (1714214) | more than 3 years ago | (#37034798)

Best answer so far.

Re:13,000mph? (3, Funny)

elrous0 (869638) | more than 3 years ago | (#37035058)

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? (1)

Dr. Spork (142693) | more than 3 years ago | (#37035210)

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? (1)

Solandri (704621) | more than 3 years ago | (#37035492)

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? (1)

luis_a_espinal (1810296) | more than 3 years ago | (#37035576)

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?

Able to circle the earth in just over 2 hours... (1)

Zanthor (12084) | more than 3 years ago | (#37034212)

That's scooting right along!

Bandwith (1)

instagib (879544) | more than 3 years ago | (#37034214)

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

Re:Bandwith (0)

Anonymous Coward | more than 3 years ago | (#37034944)

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"? (1)

circletimessquare (444983) | more than 3 years ago | (#37034242)

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"? (1)

element-o.p. (939033) | more than 3 years ago | (#37035114)

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" :)

Long walk (2)

teaserX (252970) | more than 3 years ago | (#37034288)

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

Orbit (1)

MyLongNickName (822545) | more than 3 years ago | (#37034316)

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 (0)

Anonymous Coward | more than 3 years ago | (#37034488)

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 (0)

Anonymous Coward | more than 3 years ago | (#37034804)

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 (1)

Baloroth (2370816) | more than 3 years ago | (#37034706)

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 (0)

Anonymous Coward | more than 3 years ago | (#37034838)

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 (0)

Anonymous Coward | more than 3 years ago | (#37035292)

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 (1)

amorsen (7485) | more than 3 years ago | (#37035374)

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.

Space plane (1)

Bob the Super Hamste (1152367) | more than 3 years ago | (#37034366)

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 (1)

sunfly (1248694) | more than 3 years ago | (#37034664)

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

Re:Space plane (1)

lgw (121541) | more than 3 years ago | (#37035366)

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 (1)

0123456 (636235) | more than 3 years ago | (#37035602)

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.

Ricky Bobby (0)

Anonymous Coward | more than 3 years ago | (#37034384)

I wanna go fast.
-www.awkwardengineer.com [awkwardengineer.com]

How many parsecs? (0)

Anonymous Coward | more than 3 years ago | (#37034494)

Could this vessel do the Kessel run in?

Re:How many parsecs? (-1)

Anonymous Coward | more than 3 years ago | (#37034740)

A parsec is a unit of length, not speed. So it would still be 18 parsecs for the Kessel Run... Regardless of speed.

Fag.

Re:How many parsecs? (1)

Revotron (1115029) | more than 3 years ago | (#37035088)

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

Yay (-1, Troll)

moogied (1175879) | more than 3 years ago | (#37034564)

I'm so glad we have vehicles that go 12,000mph! Any chance that vehicle can swing by my place and give me my 5,000$ in federal taxes back so I can eat some food today??

Re:Yay (1)

atrain728 (1835698) | more than 3 years ago | (#37034980)

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

Re:Yay (1)

NatasRevol (731260) | more than 3 years ago | (#37035284)

The kind developed by DARPA??

Re:Yay (1)

riverat1 (1048260) | more than 3 years ago | (#37035372)

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

your sig... (-1)

Anonymous Coward | more than 3 years ago | (#37035386)

So basically, -1 troll/offtopic is really slashdots way of saying "I hate that you thought of something before me."

No, it means I just hate you.

Why DARPA and not NASA? (1)

schwit1 (797399) | more than 3 years ago | (#37034566)

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

Re:Why DARPA and not NASA? (3, Informative)

SirWhoopass (108232) | more than 3 years ago | (#37034680)

Why DARPA and not NASA?

DARPA has money. NASA does not.

Re:Why DARPA and not NASA? (0)

Anonymous Coward | more than 3 years ago | (#37034718)

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

Friday? (1)

SiChemist (575005) | more than 3 years ago | (#37034720)

When do the semi-ballistics start running?

Re:Friday? (1)

Fnord666 (889225) | more than 3 years ago | (#37034788)

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 (0)

shdowhawk (940841) | more than 3 years ago | (#37034744)

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 (1)

jandrese (485) | more than 3 years ago | (#37034810)

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 (1)

Monkey-Man2000 (603495) | more than 3 years ago | (#37034828)

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 (0)

Anonymous Coward | more than 3 years ago | (#37034842)

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 (0)

Anonymous Coward | more than 3 years ago | (#37034850)

LOL... you're kidding, right?

Re:Around the world (0)

Anonymous Coward | more than 3 years ago | (#37034866)

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 (0)

Anonymous Coward | more than 3 years ago | (#37034928)

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

Re:Around the world (2)

lgw (121541) | more than 3 years ago | (#37035332)

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.

Who needs NASA? (2)

Animats (122034) | more than 3 years ago | (#37034776)

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. [wikipedia.org] , 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.

Not an Aircraft - more like a MARV (3, Informative)

wisebabo (638845) | more than 3 years ago | (#37034930)

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 (1)

Dr. Spork (142693) | more than 3 years ago | (#37035300)

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 (0)

Anonymous Coward | more than 3 years ago | (#37035608)

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

For an hour??! (1)

dimethylxanthine (946092) | more than 3 years ago | (#37035256)

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