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Dumpshock Forums _ Shadowrun _ China tests Anti-Sat system, US tests Railgun!

Posted by: Trax Jan 20 2007, 07:02 AM

http://www.usatoday.com/tech/science/space/2005-07-27-china-satellites_x.htm

http://fredericksburg.com/News/FLS/2007/012007/01172007/251373

Pretty interesting news on the technological front lately. The Railgun sounds pretty promising.

What's will happen next, Starship Trooper/Halo armour?

Oh wait...

Posted by: Kesslan Jan 20 2007, 07:23 AM

Both of those are really kinda old..old oldoldold.

China testing it's own version of a sat killer is new though. But the US has been playing around with railguns and massdrivers for years. Two years ago I even heard they started putting rail/mass driver tech into some sort of naval deck gun or something. The technology is known, proven to work (hell you can build your own home made mass driver easily enough) it's really only a matter of refining it and seeing what you can -really- do with it. What it's limitations are now and theoretically will be in the future with refinement. And then just how far can you go towards applying it to things such as small arms.

I mean theoretically what would be the possiblities if you could build a powerful massdriver or railgun into something the size of a pen? How powerful could such a thing ever really be assuming various power consumption and storage requirements?

Theoretically you could do it. But can you actually do it with anything resembling current or 'near future' technology?

Posted by: Thane36425 Jan 20 2007, 07:37 AM

Railguns have been around for a while, or talk about them has. The main problem is that they are very power hungry and rather large. After reading the article, the Navy is underestimating the cost of the ammunition for it. Other articles have put the cost per round at over $100,000, mostly due to the electronics.

The big problem with this is that the Navy is putting a lot of money and effort into this program while allowing others to wither. And, of course, when they get the rail gun to work, are they going to put it in a new, armored cruiser or other protected ship? No. They are going to put it in a new class of destroyer, which will incidently be tremendously expensive with all kinds of other new tech, much of which doesn't yet exist.

It just seems to be a lot of effort for a weapon that isn't that impressive beyond the "gee-whiz its a rail gun" aspect. It would be better to make a supersonic Tomahawk sized missile that could be fired from a stealthy submarine. 250 kilometers they talk about for the rail gun puts them well within range of many anti-ship missiles.

That reminds me, and this will be the last point. The Navy cancelled the battleships saying that even though the 16 inch guns were effective, they were limited to certain ships that could be lost. Well, they are going right back to the battleship now with the railgun, but it will be in a tin can not a heavily armored ship built to take a beating.

Posted by: Kesslan Jan 20 2007, 07:40 AM

QUOTE (Thane36425)

That reminds me, and this will be the last point. The Navy cancelled the battleships saying that even though the 16 inch guns were effective, they were limited to certain ships that could be lost. Well, they are going right back to the battleship now with the railgun, but it will be in a tin can not a heavily armored ship built to take a beating.

Yeah well this is why there's that constant joke about Military Intelligence being an oxymoron.

Anything on any military ship 'can be lost'. The enemy just has to blow it up first.

Posted by: Thane36425 Jan 20 2007, 07:48 AM

QUOTE (Kesslan)

Yeah well this is why there's that constant joke about Military Intelligence being an oxymoron.

Anything on any military ship 'can be lost'. The enemy just has to blow it up first.

Very true. They also don't seem to retain lessons between wars very well either.

Also neglected a point in there, that'll teach me to post in the wee hours of the morning when I can't sleep (a lesson I will probably never learn). The Navy developed cruise missiles to spread the firepower around the fleet so it all wouldn't be lost if one ship, like a battleship, were to be sunk. This further shows how they sort of learned a lesson but have unlearned it again. Same goes with the carriers. Big expensive ship full of expensive planes and a very expensive (interms of training time and dollars) crew, but it is very lightly defended against missiles and scarcely at all from submarines, bearing in mind the recent story of the Chinese sub that got within torpedo range before surfacing.

Posted by: Trax Jan 20 2007, 07:29 PM

The thing about the railguns is yeah, they have been around for years, but previously required entire buildings housing the equipment and capacitors to fire it. Now they are making them smaller, eventually being able to actually place it on a ship, with an integrated power source that all the systems will get their power from.

Also, firing the rounds and still being able to maneuver it? That's new to me.

Posted by: Kagetenshi Jan 20 2007, 08:02 PM

The move to cruise missiles was a lesson learned and two unlearned. There are only so many 1.3 million dollar missiles you can afford to destroy by slamming them into things.

(For those interested, that number is Wikipedia's price quote for a Tomahawk. The tomahawk's a bad example here, as it has a range four times that of this weapon, so we can compare it to the Harpoon instead, which has similar to shorter range and costs $720,000, again Wikipedia's estimate. If these railguns can be scaled up and maintenance costs reduced enough, they could easily become the superior option at anything but extremely long ranges—possibly even there)

~J

Posted by: SL James Jan 20 2007, 08:05 PM

QUOTE (Thane36425)

Probably because the US Navy doesn't expect there to ever be another Leyte Gulf or Jutland sea battle.

Posted by: Firestorm Jan 20 2007, 09:17 PM

QUOTE (Kesslan)

Two years ago I even heard they started putting rail/mass driver tech into some sort of naval deck gun or something.

Last I heard of Railgun/Eletromagnetic propelled stuff it was to replace the catapults of the latests CVNs, and maybe also the arresting wires.

Something called http://www.globalsecurity.org/military/systems/ship/systems/emals.htm

Posted by: Austere Emancipator Jan 20 2007, 09:47 PM

Why would they need a battleship for this? Wouldn't a ship similar to the http://www.globalsecurity.org/military/systems/ship/dd-x-program.htm be big enough to mount them?

According to the US Navy procurement budget, RGM-109 Tomahawks have a unit cost of $740k or $718k, depending on whether they are launcher from a Vertical or Capsule Launch System. Couldn't find a single reference to the procurement of Harpoon-family missiles by the Navy or the AF singe 1999, for some reason.

Posted by: hyzmarca Jan 20 2007, 11:58 PM

I must wonder exactly how much of the price tage is actual materials and labor and how much is IP-related markup.

Posted by: Fix-it Jan 21 2007, 03:14 AM

QUOTE

I must wonder exactly how much of the price tage is actual materials and labor and how much is IP-related markup.

not much. you should see the pricetags on megajoule energy storage. jeeezus.

a lot of it is just engineering in safety so you don't accidentally short the capacitor banks.

oh, and anti sattelite technology is nothing new.

Posted by: Vaevictis Jan 21 2007, 05:27 AM

QUOTE (Thane36425)

The main problem is that they are very power hungry and rather large.

64 megajoules is only about 18 kWh. That's not that bad considering that the engines on your typical warship are many megawatts.

(The real issue is the cost of a storage system that can hold that much energy and discharge it fast enough...)

QUOTE (Thane36425)

250 kilometers they talk about for the rail gun puts them well within range of many anti-ship missiles.

200-250 nautical miles =~ 370-460 kilometers.

QUOTE (Thane36425)

Well, they are going right back to the battleship now with the railgun, but it will be in a tin can not a heavily armored ship built to take a beating.

Yeah, but three differences: This weapon is expected to have 10 times the range, and the ammunition isn't launched by an explosive... and with modern weapons systems (tac-nukes, for example), it really doesn't matter how much armor you have -- if you get hit, you're screwed. You just won't benefit by having the heavily armored ships of yesteryear.

Posted by: hyzmarca Jan 21 2007, 06:26 AM

The chances of an American warship being struck with a Tactical nuclear weapon lie somewhere between slim and none if the Soviet Union reveals that its collapse was simply a ploy to lull the West into a false sense of security while it builds an ever greater war machine in preparation for its final push for total world domination. If that doesn't happen, we can be pretty sure that no tactical nukes will ever be used on a modern battlefield. No one ever used tactical nukes even when they were useful because everyone was afraid of looking bad. Now that it is all about smart this precision-guided that such weapons will probably never be deployed.

For that matter, there are pretty much only 4 ways that an American warship could possibly be sunk and thay are, in order of likely hood:
The pilot accidentally hits something big (such as an iceburg)
A meteorite hits it.
Extraterrestrials attack.
It stops on the wrong Middle-Eastern port and is bombed by jihadists.

Which is one of the bizarre paradoxes of American defense spending. Despite all of the effort we spend on bigger and better high tech weapons, we don't have anyone worth using them against. There simply are not any enemies can stand up to the weapons that we already have. And yet, while it is quite possible for us to bomb anyone (and certainly anyone who is not an ally) into oblivion with stand-off weapons, we lack the ground forces required to actually gain control of an area with any strategy short of genocide.

As for power consumption, it isn't much if you plan on firing one once per hour. If you have 4 guns firing every 4 seconds you've got 64 megawatts to worry about.

Posted by: Kagetenshi Jan 21 2007, 06:38 AM

Remember, this is meant to replace short-range cruise missiles. You don't fire four cruise missiles every four seconds—in fact, from what I can find a typical destroyer carries 8-12 of them in total, period.

~J

Posted by: hyzmarca Jan 21 2007, 06:50 AM

QUOTE (Kagetenshi)

Which is another reason current military strategy sucks. There was a time when warships with a dozen or more guns would shell crap until there was nothing left standing. In the days of self-guided cruise missiles no one understands artillery bombardment, anymore. Still, I find it difficult to believe that such guns will be able to place indirect fire with the accuracy of a cruise missile. Certainly, it would impossible without the aid of a spotter and even then if someone gets the trigonometry or the measurements wrong by a fraction of degree there will be a miss.

Posted by: Kagetenshi Jan 21 2007, 07:02 AM

Guided artillery shells exist and would doubtless be used for this, rendering it resistant to errors of the kind that wouldn't make a cruise missile miss. How the margin sizes compare I can't guess at.

~J

Posted by: Jack Kain Jan 21 2007, 08:23 AM

A few things on the rail gun taken from the article cause it looks like some people aren't reading.

"The range for 5-inch guns now on Navy ships is less than 15 nautical miles"
Ok su the 5-inch guns have a range of 15 nautical miles. Thats 17 standard miles or 28 kilometers.

"He said the railgun will extend that range to more than 200 nautical miles and strike a target that far away in six minutes. A Tomahawk missile covers that same distance in eight minutes."
Thats 370 Kilometers.

The cost of firing a tomohawk missile.
"A Tomahawk is about a million dollars a shot," McGettigan said."

The real electronic cost is not in power but in this below
" Projectiles will probably eventually have fins for GPS control and navigation.

To achieve that kind of control and minimize collateral damage, railgun ordnance will require electronic innards that can survive tremendous stress coming out of the muzzle."
I doubt the nuclear powerered navel ships will have trouble generating the power to fire one of these.

Posted by: Austere Emancipator Jan 21 2007, 09:16 AM

QUOTE (Jack Kain)

A few things on the rail gun taken from the article cause it looks like some people aren't reading.

Sometimes it's worthwhile to check up on "facts" you read from news articles, aye?

For example, the budgets are quite specific about what the actual buy-in cost of an RGM-109 Tomahawk is, and it's either $740k or $718k. Even adding the cost of the cell from which they are launched that's still $820k. Not quite a million, but close.

With the newest ERGM rounds 5" cannons can reach around 100km, although since they aren't actually in inventory quite yet I suppose they shouldn't be used for the 10x range comparison.

They are unlikely to mount these on a ship powered by nuclear reactors. All current and projected US Navy surface warships, with the exception of carriers, use combustion engines.

QUOTE (hyzmarca)

If you have 4 guns firing every 4 seconds you've got 64 megawatts to worry about.

I find it unlikely they'd mount more than two per ship. Arleigh Burke class destroyers and Ticonderoga class cruisers both can generate power in the 60-75MW range, though how much of that they can put into electricity I have no idea. The Zumwalts and other upcoming US surface warships in the same size range are supposed to use an http://www.globalsecurity.org/military/systems/ship/systems/ips.htm, which apparently means around 100MW or so for these ships, all of which, by definition, is electricity at some point.

Posted by: Nikoli Jan 21 2007, 11:26 AM

Actually, check out the show FutureWeapons. They detailed a cannon round that could self correct in flight. During two test shots, it actually got closer to the target when fired completely off course and force to self-correct.

It also allows for even close range bombardment over buildings to hit entrenched targets in the lee of the building with minimal damage to the building. The round arcs up then bleeds off lateral speed and hit much closer than expected.

Also, who know what size that railgun is, they might be able to load it on all manner of vessels which will allow dozens of ships within a fleet or carrier group (not really up on Naval strategies) to possibly carry one if not more of these guys.

Posted by: Austere Emancipator Jan 21 2007, 02:26 PM

Perhaps the http://www.globalsecurity.org/military/systems/munitions/m982-155.htm/http://www.globalsecurity.org/military/systems/munitions/tcm.htm?

By the way, I still think the http://www.globalsecurity.org/military/systems/munitions/sadarm.htm http://www.globalsecurity.org/military/systems/munitions/images/sadarm-fire.jpg.

Posted by: Cray74 Jan 21 2007, 08:35 PM

QUOTE (Jack Kain)

I doubt the nuclear powerered navel ships will have trouble generating the power to fire one of these.

Actually, nuke ships would have some trouble. Naval nuclear reactors are much heavier for their horsepower than gas turbines, and they don't answer to snap power demands well, not like gas turbines.

However, the gas turbine systems of modern warships are well up to the task.

Another point: several people have been tossing around "64 megajoule" figures. Note that's the energy in the projectile, not the energy required to launch the projectile. Electromagnetic weapons are doing good if they get 1% of their electrical energy into the projectile, so you might be looking at 6400 megajoules per shot. With an all-electric ship like the Zumwalt, you could get damn near 78MW of electricity, enough for about 4 shots an hour. (Older ships only turn a fraction of their power into electricity - that goes for the nuke boats, too.)

Another link I saw on this story said the Navy was only hoping for 6-10 shots per day. That makes me wonder if NSWC hasn't solved the barrel erosion problem that plagued SDI railgun efforts (and continues to pester railgun hobbyists.)

Posted by: Hocus Pocus Jan 22 2007, 04:56 AM

what about http://www.popularmechanics.com/technology/military_law/4203874.htmlHypersonic Cruise Missile: America's New Global Strike Weapon. attatck anywhere in an hour?

Posted by: Cray74 Jan 22 2007, 01:26 PM

QUOTE (Hocus Pocus)

what about http://www.popularmechanics.com/technology/military_law/4203874.htmlHypersonic Cruise Missile: America's New Global Strike Weapon. attatck anywhere in an hour?

Given the trouble developing a working, hypersonic air-breathing engine, I'm not going to hold my breath on the ramjet. The Trident-based kinetic kill weapon is interesting.

Posted by: Austere Emancipator Jan 22 2007, 02:08 PM

What are the main problem areas? An Air Force ground test engine has shown, as part of the HyTech program, that it will at least function in the 4.5 - 6.5 mach range, but of course that tells us nothing about thrust or fuel consumption or anything like that.

[Edit]Just re-reading some of the stuff you've said about scramjets here earlier, so no need to post anything unless you've got something new since late 2004.

After reading through your links, etc., it seems most of the criticism is specifically about effectiveness for large structures, long distances, or getting outside the athmosphere. The missiles, with ranges topping around 1000km, seem about the only logical use for the technology. So we'll just have to wait and see if any of the various people working furiously on this actually makes one work properly.[/Edit]

Posted by: Thane36425 Jan 22 2007, 04:48 PM

QUOTE (Hocus Pocus)

what about http://www.popularmechanics.com/technology/military_law/4203874.htmlHypersonic Cruise Missile: America's New Global Strike Weapon. attatck anywhere in an hour?

That's interesting. However, the Russians already have a supersonic missile called, by the West, Shipwreck. It a big thing with a 1,600 pound warheadand flies at Mach 2.5. They were designed to kill US carriers and the swarm of missiles could actually talk to each other to coordinate the attack. The Russians copied our stuff throughout the Cold War, this looks like something we should copy.

Posted by: Austere Emancipator Jan 22 2007, 05:41 PM

They have several supersonic surface missiles. Since http://www.globalsecurity.org/military/world/russia/ss-n-19.htm they've also produced at least the http://www.globalsecurity.org/military/world/russia/moskit.htm. The Chinese also have the http://www.globalsecurity.org/military/world/china/c-301-specs.htm and http://www.globalsecurity.org/military/world/china/fl-7.htm. The Moskit and the C-301 use ramjets, too.

Posted by: FlakJacket Jan 23 2007, 02:02 AM

QUOTE (Cray74)

The Trident-based kinetic kill weapon is interesting.

Interesting in an incredibly unnerving way. Such a lovely turn of phrase "nuclear ambiguity issues."

Posted by: Fix-it Jan 23 2007, 03:27 AM

Changine the subject again, anyone read that article on how the Marine Corps wants to develop orbital dropships?