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he acquisition of these technologies resulted in China's production of more advanced surface combatants during the past decade-- including a single 6,000-ton Luhai-class guided-missile destroyer (DDG), two Luhu-class DDGs (4,200 tons), and nine Jiangwei-class frigates (2,250 tons). These units are equipped with the HQ-7 or HQ-61 short-range air defense systems that likely will be replaced by a longer-range vertical-launch system within the next three to five years. These ships also have integrated tactical data systems, an improved antisubmarine warfare suite that includes embarked helicopters, and gas turbine propulsion.

Notwithstanding these improvements, the backbone of the PLA surface fleet remains its 16 aging Luda-class destroyers (3,250 tons) and 30 Jianghu-class frigates (1,425 tons) that are largely inadequate to meet the requirements of modern warfare. The planned acquisition of two 7,940-ton Russian-built Sovremenny-class DDGs in the 2000 to 2001 period will improve the PLAN's surface-combatant capabilities. These units are likely to be equipped with an advanced SAN-7 air-defense system, the KA-28 Helix Helicopter, and SSN-22 cruise-missile technology. The PLAN's HQ-61 and HQ-7 systems are based on the French Crotale land-based surface-to-air missile system, and they do not provide surface units with an effective area-defense capability. This deficiency makes PLAN surface units extremely vulnerable to air attack.

keep dreaming...

http://www.navy.com/navyofthefuture/ddx

"Crew: Many of the functions performed by crews on conventional destroyers will be automated on the DD(X). That means a reduction in crew size - 330 fewer sailors than the Spruance class destroyers and 200 fewer sailors than the Oliver Hazard Perry class frigates. The crew will also focus on fighting versus ship maintenance."

http://www.navyleague.org/sea_power/apr_05_46.php

"Part of the 1,200-man reduction in the size of a carrier crew planned for the CVN 21 next-generation carrier will be accomplished by installation of the new launching system and arresting gear."

While you can "use the same substance" as you suggest, it's doubtful that you could maintain the perfect mirror on the missile, or for that matter even achieve such a mirror.

I am not talking about a "perfect mirror" Let's say I can reflect 95% of incoming energy well you now need a system that's 20x as powerful. Can this be done? Well every part of your system now needs to take 20x the load including that targeting mirror. As to Masers you need to have 2 to 4 of them to cover each section of the ship. And they now need to swivel fast enough to take out 3 targets in under a second. And we are talking about moving 100's of Tuns of stuff at those speeds. Depending on the frequencies I can still reflect some of that energy but lets say they only need to be 5x as powerful.

Now let's place these things on a battle ship. Well a dumb kinetic bomb that is filled with paint can take them all out. It's not explosive so hitting it wit a laser is not going to do much. And it's a kinetic weapon so shooting it is not going to do anything. A fine mist of pant on the outside glass of your Masers is going to break said system after a single fire. Yep, it adds a new arms race but not much of one at that and your spending BILLIONS to build something that a can of paint can break.

This could still be done but we are a long way from any system that comes anywhere near this level. Lasers sound cool but a rail / coil gun is much more useful at point defense. And even still these systems are useless vs. the WWII method of shooting a few ton's of led out of a gun at your ship.

As I said "unless there moving at slow speeds at which point you can just use gun powder to do that"

http://www.navyleague.org/sea_power/may_04_10.php
http://www.raytheon.com/newsroom/articles/ddx_jane s_062403.pdf
http://www.strategypage.com/messageboards/messages /8-6263.asp

These are all low velocity rounds.
Note: Mach 10 is slow when you're talking about rail guns.

The idea behind rail guns is you can take a 1lb iron dart and fire though 10 feet of carbon steel so you can then keep 20 tunes of said darts in less space and with less danger than you could other types of ammo. These systems are based using more massage darts, which either use an explosive head to penetrate the target or the weight of the dart. But as I said these systems could use gun powder they are not the "rail gun weapons" your thinking of as they are no better off than normal guns.

PS: Except when it's not.

" the ship was only able to carry such a system because it was a heavily overpowered Orion warship. (It carried several space shuttles up into space with it.)"

Your talking about sci-fi as if it real. It's not. You can't say look at what this fact sheet says because it's sci-fi. It's like saying "If you could take all the energy from the sun for 2-3 seconds you could cut a one inch hole though the earth" And then point at that and saying see you can cut a one inch hole though the earth. If you sit there and think about the logic you can see why saying "if I can do A then I can do B" does not mean you can do B.

SCI-FI is fiction. Please say that again and again till it starts to sink in.

Except when it's not. The archangel's design is considered sound by scientists and has been discussed several times on nuclear science webboards. I've asked nuclear scientists outright if the archangel's defenses would work. The answer was a resounding 'yes', along with an explanation about the issue with reflective surfaces.


Yes, Masers can use wavelengths higher than visible light but if your going to use some sort of mirror to target your system then clearly you can use that type of mirror to reflect that energy at 99+% efficiency. At this point in time your talking about a hypothetical system so feel free to pick any part of the EM Spectrum and you can find it's going to be a pain to use as either you need to rapidly swivel your laser system or you going to lose a lot of energy as it passes though the air or you can use the same substance used in your mirrors to make a missile immune to said system.

We're discussing both systems, so it's only fair to mention both. Lasers have a faster targetting system than masers (due to the ability to reflect visible wavelengths), but masers are able to penetrate better due to higher wave lengths. Both have advantages/disadvantages that to be weighed in before deploying a system. A mirror on a high powered laser is doable, but has to be precision crafted to be able to take the load. Note that such a mirror is vastly different from a "reflective surface" on a missile. From here:

The optical power levels inside the laser devices themselves are so horrendously high that the high-reflectivity laser mirrors operate just on the verge of self-destruction. Any flaw or blemish or dust particle on the mirror surface causes the mirror reflectivity to decrease or its absorption to increase. As the absorbing spot gets warmer, its absorption goes up, and the situation goes to pot in a runaway fashion. The result is near-instantaneous catastrophic runaway thermal damage which blows the surface off the mirror faster than you can possibly shut things down. The supersonic nozzles are
extremely fragile and touchy also.

While you can "use the same substance" as you suggest, it's doubtful that you could maintain the perfect mirror on the missile, or for that matter even acheive such a mirror.

You can't fire rail guns over the horizon as they a lose a lot of kinetic energy going tough the air and don't don't have ballistic trajectories unless there moving at slow speeds at which point you can just use gun powder to do that.

You obviously haven't seen the Raytheon specs on the new railguns. They fire a non-explosive, guided projectile straight up, then direct it to the target on the way down. Over the horizon is *EXACTLY* what it does, and it does it with a range of ~100 miles. (Or so the brochure says. :-)) Some links:

http://www.navyleague.org/sea_power/may_04_10.php
http://www.raytheon.com/newsroom/articles/ddx_jane s_062403.pdf
http://www.strategypage.com/messageboards/messages /8-6263.asp

I'd provide a link to the munition itself, but I can't find the article at the moment. If I find it, I'll add it in another post.

Well I know the story is already two hours old (gasp), but it appears to be ill-supported. The linked article plainly states ...

1. That this warship class will enter service in 2011:
"When the U.S. Navy's first integrated power system (IPS)/electric drive warship arrives in 2011 as the DD(X), the service will mark a technological breakthrough ..."

2. That this warship class will debut without a rail gun or any other advanced weapon system:
" When the new ship arrives in service it will be armed with very advanced, but conventional weaponry, including two United Defense 155mm Advanced Gun System cannons and an 80-cell vertical launch system for various guided missiles. But these systems are stepping stones to greater capabilities ..."

3. The Navy won't even decide whether to fund a rail gun for years:
"Whatever investment decisions are made for weapons the next several years, the Navy already is engineering the potential these technologies require, according to Collins and his IPS/electric drive team for DD(X)."

The speculative linked white paper goes no further, advocating that a rail gun *proof of concept test* *could* happen by 2008:

"A focused technology development program that leads to a series of experiments that culminate in a full-scale extended-range naval rail gun proof-of-concept demonstration in fiscal year 2008
is a sensible approach."

For a sense of how little this means, consider there was a successful "proof of concept" demonstartion for airborne anti-laser systems -- "Star Wars" SDI technology -- in 1984.

Other sites are also covering this -- without needing to use acrobat reader.

I can't read the original, but according to the link I'm including, they're not just talking railguns - they're also talking free electron lasers and masers. Now, if only they'd provision a banana-fana-fo-faser, we'd be set.

thankyou for the clarification of the urban legend. A quick google check showed a lot of sites still reporting the sheffield as being made of aluminum(which was merely my recollection of the reported events back then), but enough with cred, like your link, prove otherwise, so I stand corrected with this material science refresher. Thank you. They did switch back to all or mostly all steel though for new ship design,from various problems with aluminum (mostly it is not that great for armor), some mention in the article in the following link.

For anyone interested, who might not have been around to remember this short but nasty war,here is a link to a short history of the conflict

Although I can't find it now, I would swear I just read something regarding China's efforts to modernize and expand their naval ability in World Press Review. Anyhow, this article by the 'Navy League of the United States' seems to take a pretty middle-road look at China's navy, coming to the conclusion:

" In the coming de-cades, the Chinese Navy presents the real likelihood of expanding its capabilities significantly. As it does so, it also is likely that Beijing will increasingly view the Navy as a mechanism to exert pressure on China's neighbors and to assert its influence regionally."

I am not as convinced today as I was several years ago that 'China's saber-rattling is just bluster' -- they seem to be making progress towards modernizing and expanding their naval fleet...

There's a Thyssen system that uses liquid oxygen, diesel fuel, and argon. The liquid oxygen and argon are mixed to produce an "air" mixture for the engine, and then the argon is separated from the exhaust and recycled. This requires much less storage volume than carrying compressed or liquid air. Something like this is probably what's being discussed.