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Navy Tests Mach 8 Electromagnetic Railgun
hargrand writes "Wired magazine has a story and publicly released video of the Navy test firing of a 32 megajoule electromagnetic railgun: 'Reporters were invited to watch the test at the Dalghren Naval Surface Warfare Center. A tangle of two-inch thick coaxial cables hooked up to stacks of refrigerator-sized capacitors took five minutes to power juice into a gun the size of a schoolbus built in a warehouse. With a 1.5-million-ampere spark of light and a boom audible in a room 50 feet away, the bullet left the gun at a speed of Mach 8.'"
100 mile range? Put these on every U.S. Naval vessel within 20 years and we will have Oceanic Hegemony! Hahaharrr!
You'll finally dominate the USSR militarily, ending the Cold War.
I've heard that before "Rule Britannia, Brittania rules the waves...".
I'm still trying to get them kids off my lawn. But kids on bikes are quick, wily and seem to move in Brownian Motion tracks. Mach 8 could give me a good tactical advantage . . .
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
So if they pointed this sucker 'up' would it be able to throw stuff (you don't mind being squashed - a bit!) into orbit?
Eclectic beats from Leeds, UK
handmadehands.co.uk
...bullets made out of solidified seawater with a nearly endless nuclear power supply and you got yourself a inexpensive mass weapon platform that just won't stop.
The bolts that hold the gun to the floor look quite impressive in the video, but clearly not impressive enough.
Now they need another year to re-align all the pieces of there gun...
Why is there so much smoke?
...I would be also interested to see what the projectile does at the "destination". Time to buy me some kilofarad supercaps :)
"The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
It took a lot of time but they managed to outfit the Tollan Cannon finally! (Obscure obligatory Stargate reference)
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This might have been the ideal plot for a "survival" game for the 8-bit platforms. The mighty cannon takes 5 minutes to charge...the counter starting from 300 and dropping down...hordes of enemies crowding the cannon, some turrets or else controlled by the player which shoot down the enemies...I can even hear the frenzy music created by the oscillators of the C64 SID...Great plot, indeed.
Summary says the boom was audible in a room 50 feet away? If I tip over a chair, it's audible in a room 50 feet away...
http://en.wikipedia.org/wiki/Super_High_Altitude_Research_Project
The Super High Altitude Research Project created a gun that accelerated a four inch diameter projectile to mach 8.8 . It was more than 400 feet long and parts of it weighed a hundred tons. So getting to mach 8 using something only the size of a school bus is a pretty good accomplishment.
Could the rail gun put something in orbit? No. The SHARP was intended to put things into orbit and needed to be improved to mach 21 to achieve that goal.
palladiumbooks.com tell you how to make one...
lol even 50 yards would be ridiculous.
As it is defined as a ratio of two speeds, it is a dimensionless number. At Standard Sea Level conditions (corresponding to a temperature of 15 degrees Celsius), the speed of sound is 340.3 m/s[3] (1225 km/h, or 761.2 mph, or 661.5 knots, or 1116 ft/s) in the Earth's atmosphere. The speed represented by Mach 1 is not a constant; for example, it is mostly dependent on temperature and atmospheric composition and largely independent of pressure. In the stratosphere, where the temperatures are constant, it does not vary with altitude even though the air pressure changes significantly with altitude. thus mach 8 at best is an escape velocity of 9800KM/H
As a non-American, I can say the US will remain a superpower as long as it retains the two G's: grain and big fricking guns. Food and firepower and fuel are a war machine's most important components. Of the three, fuel is the one most easily rationed. The US has too many cars, a personal luxury that can be temporarily foregone for more economical modes of transportation like trucks and buses. Were the US to outsource its defense industry and agriculture, it would lose its superpower status within a decade.
FTA - test fired by the US Navy (the summary doesn't make this clear)
Hmmmm... The Washington Post article said Mach 5. In fact, it seemed more informative in general. http://www.washingtonpost.com/wp-dyn/content/article/2010/12/10/AR2010121007437.html
that is, ... almost as loud as dropping a frying pan. Very impressive.
??? Altough I still own the machine, I don't recall that game...
I've got better things to do tonight than die.
Only one Quake2 reference, and none to Bayformers :(
I've got better things to do tonight than die.
So basically the Navy was like: "Come see us shoot stuff with our big gun."
... encounter a Mach 8 projectile.
As regards civilian uses, this is a potential way to put bulk materials in orbit in a hurry. Nothing living or delicate could take that 100 Gs, (or whatever) but you could send up a lot of air/food/water/clothes/tools/ etc, and they would arrive in orbit in perfectly good shape.
low orbit velocity = mach 24
wake up and hold your nose
The way I see it, there are several reasons why the USA would want to build Railguns:
- They have info that aliens exist and can come to Earth. - They have confirmation that someone (e.g. China, Iran, North Korea...) really plans to attack the Western World (or only the USA). - They are planning to conquer the World in the next 10-20 years. - Or they are really just being careful and making sure they can face the unexpected.
You're an idiot, but you know that right? You're list shows you have no real critical thinking skills beyond what you learned from apocolyptic comic books, movies, and video games, but that doesn't stop you from trying act like you have deep thoughts.
The reason I am assuming you know you're an idiot is because you post as AC and have that little scrap of pride.
Try this: They've been working on railguns for ages, as a launch system for ballistic missiles, manned spacecrapft, projectiles, and other purposes. Electronics and triggering systems from that research make their ways into other areas.
Also, you always want to make your systems portable, safer on home turf, and easier to handle.
"Safer on home turf." The problem with explosive delivery systems like cannons, rockets, and guns is that their is a risk of blowing yourself to smithereens. If you can eliminate that from projectile delivery, you become more effective.
Do try to use your brain.
Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong fix.
I was wondering about the smoke two. My guess is it's some combination of the following:
* When the slug is fired by the railgun, their is surface friction between the slug and the rail. With that much kinetic energy, the friction, even if they have used very high-step tech to minimize the friction, will probably super heat some of the material of the slug, the rail, or both, so that might be some material which broke free and started to burn?
* Effect of air resistance on the slug, moving at mach 8+, might cause some of the slug material to super heat, and burn off?
That's only 44,280 hp*s (horsepower per seconds). It's hurling a small object at a speed of only 16.3 million furlongs per fortnight. They need to get it up to at least 88 million fpf...
What those who want activist courts fear is rule by the people.
if the GOP did what they complain about they would cancel this useless program.
If aliens attack, having railguns instead of missiles will make absolutely no difference. If they want to protect against somebody attacking the wester world they'd need weapons that protect against current threats, not WWII ones. Ditto for they wanting to conquer the world. If they just want to be carefull, well, how many hypotetical threats does a railgun avoids?
I see three possible explanations for that. 1) It's basic research. Researches are just wanting to study things that there is no money for, so they put an weapon-like name on it, and get the money. 2) It is space research. The same situation as basic research, but with a bit faster rewards. 3) Somebody is getting a lot of money from the government.
Rethinking email
was listening to Gimme Shelter at the time this came up... wow...
War, children, it's just a shot away, it's just a shot away...
Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
acceleration. IIRC, the projectile reached Mach 8, about 2700 m/sec. It's an unpowered projectile, so it got all its velocity in the railgun, which I'm going to estimate as about 100 feet long. Call it 30 meters long. Let's say that its velocity increase during the firing was linear with its change in position in the gun, so we can approximate its average velocity in the gun as 2700/2 = 1350 m/sec. This gives us a time in the gun of about 30/1350 = 0.022 seconds. Since V (muzzle velocity) = a (acceleration) * t (time during which velocity is changing), we can figure out what acceleration that puppy had to endure to go from zero to Mach 8 in 22 milliseconds.
Ta da: (1350m/sec)/0.022 sec = 61,363m/sec^2. Since Earth's gravity is (IIRD) 9.8m/sec^2, we're looking at over 6 thousand Gees.
Clearly, no wetware is gonna make it through alive. Ditto for normal fabricated parts & stuff. Lots of electronics and explosives will handle it (cannon shells, for example), but there we are, squarely in military applications.
There really aren't any civilian applications for this. It does present some fascinating problems in science (plasma & hydrodynamics) and engineering (BIG pulsed HV supplies, keeping things together in the face of incredible Lorentz forces, etc.), and it may keep civilian scientists and engineers imployed, but really - it's a military technology.
Charging 33Mj in 300s is only 110KW. A US house typically takes from the grid 200A at 220V: 44KW max (uses a special panel to distribute it; standard is 100A:22KW). So two neighbors and I could charge this thing in just about 4 minutes. It consumes only 9.17KWh, which costs under $1 from the average US grid utility. A US car floored at about 200KW would charge it in 2m45s.
Of course the real action is in the firing, when 33Mj is released in (FTA) 10ms. That's 3.3GW, which powers 1.65 million typical US homes (typical SF-sized city + immediate suburbs) at their 1KW average consumption (non-electric heating: if all electric heated, that's about 200,000 Northeast homes in January). At about 35Mj:gal that's only about 9 gallons of gas at 100% efficient electric generation; a typical high-end generator at 20% needs about 45 gallons for each shot.
Of the storage, quick charging and even quicker discharging this railgun demonstrates I hope the Navy produces even more productive research in just the storage and quick charging efficiencies. Naval ships probably won't want to wait 5 minutes, or even 5 seconds, to reload, so 1.1MW charging is a good target. I don't know whether these capacitors charge in a massively parallel array, but they should; I'm not really sure why all modern batteries don't charge many subcells in parallel for faster charging than discharging - though this gun will never achieve that rate, even if charged on shore by a nuke plant (typically 2-3GW). More research, especially basic science in electrochemistry on nanomaterials, would improve electric appliance performance, especially in our critically growing mobile devices.
But storage density is the key factor. Destroyers typically carry about 200Kgal of fuel retaining about 25Kgal reserve, plus about 30Kgal jet fuel. A fuel cell at 70% efficiency would need only about 22 gallons per shot; 1000 shots would be less than the reserve. These caps are designed for fast charge/discharge, not capacity, since they're much larger (at least a couple shipping containers, over 5000 cubic feet, instead of 6CF). We need supercapacitors that can store greater than gasoline's 35Mj:l (and better than its 45Mj:Kg). At large scales, capacitors should be much smaller and lighter than gasoline, since each cap atom should store more electrons than in the one or two max in each chemical bond in fuel molecules (and which never completely, or even mostly, "discharge"). This project probably won't do that kind of research, but it could feed other research into that much harder and more common problem of increased storage density.
In the meantime, it's great the Navy will be able to move to very powerful electric guns. Instead of fuel energy locked up in separate propulsion turbine tanks and ammo charges, the whole mission can be more flexible with electric powering everything. Fuel cells can double or triple (or better) the conversion efficiency, while eliminating emissions (and generating drinking water at sea with no extra energy consumed). Which all means more efficiency, which means less fuel carried around, which means even more efficiency. Ships might eventually carry square KMs sheets of solar panels to float around them, generating a megawatt (in daytime) for charging caps that fire every 5 seconds or faster.
And the more we get the Navy energy efficient, the less the Pentagon will demand we stay at war to protect global oil supplies, and the more it will prioritize energy innovation that keeps America more independent and effective generally. Which means less shooting, which is the real (and only legitimate) goal of the military: to end wars with America victorious, either by superior force or by avoiding them entirely.
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make install -not war
Do these shells really need to be solid metal? Electric charges form only on the surface of metal objects. Couldn't the shells be just some tough kevlar bag coated with metal for acceleration? Filled with water to deliver mass and keep an aerodynamic shape, that probably will be forced into the most aerodynamic shape by shoving it through the air. That would mean the ship could carry just the empty bags, filling them with seawater. That saves a lot of weight and space on the ship, which means a larger arsenal and longer range (and time between refueling). Indeed, if the ship carries several square KM of solar panels, daytime sunlight (over a MW) could charge a shot every 3 seconds, or (if stored) at least every 10 seconds through the night. Which means the ship's arsenal would be limited to the number of bags it could carry, which is probably hundreds of times as many as the shells the carry now. If the bags could somehow be produced at sea (perhaps from fish or kelp, or the floating plastic trash islands), these gunships could fire continuously, indefinitely, especially since the guns and their charges have few moving parts with very little friction. Docked and connected to shore power could deliver that kind of arsenal practically anywhere in the world.
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make install -not war
Mach 8 is about twice as fast as a rifle bullet, but modern anti-tank guns (APDS) start at about Mach 9 (admitted).
For an experimental breadboard rig, though, Mach 8 is pretty impressive.
Can I have one in a 9MM PPK form factor, please?
--dave
davecb@spamcop.net
This kind of R&D will lead to new ultra-caps, but also a much better understanding of how to make things go fast CHEAPLY. For the moment, this is about throwing 25 lbs 200 miles. Once this is done, then we will likely see a new one that will be capable of throwing 1000 or more lbs STRAIGHT UP say 200-300 miles. Once that occurs, it would be possible to send up very cheaply water and nano sats designed to withstand that kind of Gs.
I prefer the "u" in honour as it seems to be missing these days.
as a payload, and probably other bulk materials that would be valuable for space-based activities. You can imagine liquid oxygen (good for a propellant and breathing), UDMH and N2O4 (storable propellants), and other stuff.
The projectile will get very hot, but not for long. A design with a thin ablative skin and an underlying layer of thermal insulation would probably make it through the atmosphere.
There are many studies of rail gun/magnetic launch/etc. systems for putting bulk materials in space. Atmospheric drag is a big term in the energy budget, and IIRC, there could be significant advantages to getting above some of the atmosphere by launching from high elevations.
To suggest that people in Western Europe want their governments to spend money on American weapons is a little odd, I think.
Reality is defined by the maddest person in the room
Why isn't the projectile fitted with some kind of streamlined nose?
No aerodynamicist but I hazard to guess a flat surface perpendicular to the direction of motion is not optimized for minimal drag.
I'm guessing all the Navy's budget went to the 1st class videographer who manually panned the camera so precisely to follow that traversing Mach 8 projectile.
I don't know if education works optimally unless people have to earn the opportunity for an education, not just offering a way to earn a degree. You can give people tuition and they'll go, but if they don't have an appreciation for the cost of what they've been given, they're likely to spend as much of the time as possible partying, squandering the opportunity they've been given.
We should first drop free public high school education before dropping help with college tuition. This would in effect nurture people to appreciate education *BEFORE* it's too late. Saying we shouldn't sponsor kids into college is like trying to hide the syptoms of disease instead of curing it. I expected more from slashdot.
Once you start despising the jerks, you become one.
As of 2007 the top 20% of American households have 80% if the wealth. Of this the top 1% had 34% of the wealth and the other 19% had 50%, leaving roughly %15 for the rest. In human terms if you split $100 among 100 people, on person would have $34 and 80 people would average around $0.19. The pattern of the fewest having the most repeats, so the group averaging 19 cents each will have a lot more people with 1 cent or less and a few having more then the average.
This is not a recipe for a world leading economy, or even a viable country. It is poison to democracy. The long term prospects are not good for the US.
Why is Snark Required?
The main advantage of a rail gun is that its muzzle velocity is not limited by the sound speed in a hot gas. Guns that use chemical propellant can't have arbitrarily high muzzle speeds because the propellant gas can't be arbitrarily hot. If you want to go faster, you have to switch from a gun to a rocket and carry the propellant with you. A rail gun gets you back to a gun with rocket speeds and ranges but faster. Since the response can be faster than a rocket, it can provide missile defense by the barrage method and be very effective. It could also be used as intercontinental ballistic artillery eventually. Very powerful and destabilizing....
Technology isn't intrinsically good or evil. It's how it's used. Like the Death Ray.
It is difficult to understand how you could have pulled that BF quote so far out of context. It was referring to the devaluation of currency being effectively a tax and was not related to income tax whatsoever. If anything is would be similar to a tax on the value of savings and investments (not the numeric amount), due to inflation.
Even if it were referring to income tax (e.g. "the most equal of all taxes...is generally proportional to Men's income"), it is per the wording not a progressive tax. A Tax is a nominal value of money paid for some reason, not a rate. Progressive taxes are by definition defined by a tax RATE that is proportional to income/assets/whatever. In a progressive tax, not only does a person with more taxable assets pay more in taxes due to a fixed percentage of the larger value... the percentage itself rises. This is not what is referred to here. Fail.
(Now one could argue that a flat tax on paper assets integrated over time is a progressive tax, since wealthier people would potentially have more money "in the bank" being taxed in relation to total assets, which may be true... The interesting bit about that is it would punish those who saved paper assets, which would likely result in the wealthy moving away from that paper currency as a container of wealth. Franklin argued against use of Gold and metals as wealth containers since the prices were volatile at the time, and with paper effectively taxed, by deflation, other methods of escaping the deflation would likely be sought.)
If you can look at those charts and see any trendline I applaud you. To me it appears the numbers are statistically brownian noise.
Your first paragraph is ok, but then you dive into the deep end... You give no basis for why para 1 is "poison to democracy". Speaking of which, what is this Democracy to which you refer? People like you, with no basis in economics, or civics, are what make the long term prospects of the US "not good".
It's thought that the Russian nuclear program would have happened years earlier if they'd tried to do it themselves, rather than replicate the American's based on smuggled partial plans.
At 1.5 mil amps and that many joules, you might as well just skip the middle man and fire the electricity itself at them lol.
Google's Super Secret Search Algorithm: SELECT @search_results FROM internet WHERE @search_results = 'good'
Things are far more evenly distributed right now than they have ever been in the entirety of recorded human history, and certainly for the period that the US has been in existence.
You could make arguments that are valid using the data above, but the ones you make in your last sentence are laughable at best if you're going to base them solely off wealth distribution numbers. Unless, that is, your actual intent is to argue that greater distribution is poisonous and not good for long-term prospects or a viable country. If that's the case, some practice in effectively communicating your point is in order. :)
So long as people are inherently unequal in ability, the distribution of wealth will be unequal to some extent or other.
A gun that shoots at a velocity of Mach8 is not sufficient for getting an object into orbit. But it is a sufficient speed for operating a SCRAM jet.
The described gun is great as working demonstration of the technology. Now build a longer gun that accelerates a larger object at a lower acceleration and you have a feasible means of launching SCRAM jets that could get smaller satellites into orbit. Because the projectile also accelerates, the problems you described are minimized. The gun gets the jet into the upper atmosphere and the SCRAM jet accelerates it so that it can escape orbit.
It's a Quake thing.
Also, income != wealth. Saying that the rich "pay too much" is to ignore that assets are not taxed as income.
And now we come to the crux of the matter, the fact is you simply can't tax the wealthy enough to acheive your goal, unless of course you tax them at over 100%; which leaves you with unvarnished wealth redistribution. My belief is the wealthy have had ancestors with almost obsessive-compulsive drives to make their grandchildren rich and have embarked their families on multi-generational plans to achieve that goal. They have frequently dragged many around them with them. I fear that when you increase inheritance taxes to the point where that is impossible, then society will lose a valuable motivater. Perhaps it's not the top 20% having the 80% that is the real problem with a sick society but the appearent inability of the lower 80% to produce more wealth. How do we teach the average joe to be wealthier rather than just have more income?
Apocalypse Cancelled, Sorry, No Ticket Refunds
This article contains no useful information. Nobody cares about railgun speed records, because the design has an fatal durability problem.
Railguns are limited by the erosion rate of the rails by the propulsive arc discharge, and no progress has been made on this issue since the thing was invented. If any of you geniuses want to make an important contribution to the future of mankind, solve that problem, and the Pentagon will pay you more money than you could ever imagine.
This article was only posted so that the Navy could justify their fat budget for a gizmo that offers no hope of ever being used.
Because this bullet is going a VERY short distance.
I prefer the "u" in honour as it seems to be missing these days.
I'm curious...Mach 8 is somewhere around 2700 m/sec. I understand there's a rule of thumb that says the gas shock temperature in K in front of a projectile is roughly equal to the projectile speed in m/sec.
(http://en.citizendium.org/wiki/Atmospheric_reentry)
2700K should heat the forward surface of the projectile quite a bit, and it would only have to get to around 800C to glow in the visible spectrum. Is the flight time just too short for heating to visible radiation temperatures? Anybody know why the projectile isn't glowing? Inquiring minds want to know....
Those people that left their families a ton of money didn't expect to die quite so soon. Otherwise they'd have bought way more hookers right there at the end. Tax their inheritance at 90% and you'll lose no motivators except the motivation for their children to not bother applying for a job.
That was the plot of an old animated series called "Space Battleship Yamato". In it the titular vessel was equipped with the massivly powerful "Wave Motion Cannon", a weapon so powerful it can vapourise an entire fleet of enemy ships with one shot; however, it takes 5 minutes to charge before firing and requires all non-essential power systems be deactivated, leaving the ship powerless and adrift until the weapon is ready.
Every episode ended exactly the same, the crew of the space battleship having exhausted every avaliable solution to the problem panicing for a very tense 5 minutes before the weapon fires. Then someone says a corny one liner and the credits roll.
Dungeon Tactics : Free Open Source SRPG
if only the instructors would evaluate the students performance in the college classroom like tests and grades in high school.
I may have missed someone mentioning this, but the reason for these guns on ships?
Three-quarters of the world's mega-cities are by the sea.
Around 80 per cent or so of people live within 60 miles of the coast.
Our fleets would be able to be a very credible threat to land-based targets/populations, especially... oh.... I dunno.... Shanghai? Beijing? Who wouldn't want to stand off a hundred miles or more, completely untouchable by their long-guns, while we have subs, aircraft, and AWACS, and CIWS, and so on, to protect them from other ships or aircraft.
"A government is a body of people usually -- notably -- ungoverned." -Shepherd Book
http://www.pdfernhout.net/recognizing-irony-is-a-key-to-transcending-militarism.html
"There is a fundamental mismatch between 21st century reality and 20th century security thinking. Those "security" agencies are using those tools of abundance, cooperation, and sharing mainly from a mindset of scarcity, competition, and secrecy. Given the power of 21st century technology as an amplifier (including as weapons of mass destruction), a scarcity-based approach to using such technology ultimately is just making us all insecure. Such powerful technologies of abundance, designed, organized, and used from a mindset of scarcity could well ironically doom us all whether through military robots, nukes, plagues, propaganda, or whatever else... Or alternatively, as Bucky Fuller and others have suggested, we could use such technologies to build a world that is abundant and secure for all."
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
We just need to build a 133MJ Gauss Cannon! Get on it Military!