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Robotic Gliders Soar Underwater
zymano writes "Yahoo has this tech news on ocean gliders that can go on journeys for hundreds of miles and last for weeks using pumps that push ballast water in and out to subtly change their buoyancy. This enables them to alternately rise and fall through the ocean as they glide forward. Oh , $60,000 if you want one." See our previous stories for more information.
Preliminary analysis of the design suggests its shape should produce speeds up to 10 times as fast as today's gliders, which fly at a pokey half-mile an hour
That is a whopping 5 miles per hour... you won't be able to swim with many schools of fish - or keep up with that russian sub, unless you are being towed by it. It is neat, but slow.
They don't run on ocean currents. By changing their bouyancy, they provide a downward or upward force, which is translated to a forward force via the wings.
No. That is not the obvious use. The obvious use will be delivering a nuclear (or large conventional) payload in the middle of an enemy port undetected. These things can be made as stealthy as the submarines never ever got. They make no noise. They can be made to have near zero magnetic signature. If you are not in a hurry they can go half the way acrosss the pacific if needed.
Fsck... The possible applications outright scare me. And at 60K they are only a fraction of the price of a missile. The only problem is navigating in shallow water, but this can be solved as well at around 60 more K.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
So last time you checked, thermal energy didn't work? Odd, I'm pretty sure I didn't turn that off...
Seriously, I can see two ways of doing this: Either you find some way of bringing the heat from the upper layers down to the colder ones and tap part of the energy as it radiates, or you bring up somethign cold from the deapth and tap part of the energy as it is warmed up. One system I saw described in a popular science magasine a few years back involded phasechanging wax from solid to liquid and back again.
Basicly, to 'sip' power from seawater is not significanlty different than making electricity with geothermal energy - it's just a bit harder to pack all the bits into a tiny topedoshaped hull.
Everything in the world is controlled by a small, evil group to which, unfortunately, no one you know belongs.
The thing works on gaining and losing elevation, so if there's a temperature gradient at different depths, well there you go. Or maybe they're talking about the hot springs where steam comes up through fissures? I don't know. But there's certainly some energy there, enough to support life in fact.
the only problem with hunting down enemy subs is that the glider is too slow to keep up with a modern sub. the article points out that the current design only does 1/2 mph, and the navy's latest design goes at about 5 mph (which has to be a w.a.g. because i am sure the actual figures are way classified.)
1)surface water is warm
2)deep water is cold
3)these things go up and down
4)apply thermodynamics.
Pump the water to the front and it glides downhill in that direction, just like an air glider, while you use the rudder to set the direction. When you are deep enough, pump out the water and the front rises, letting you glide uphill in the direction you wish to go. It's just simple physics and simple aerodynamics. You are trying to make it too hard. You use the force of gravity to sink. (Does that mean you use the force of anti-gravity to rise?)
But that's for sub-to-sub situations, when both guys want to hide their location. If instead of a submarine you're manning, say, Miami, then your best efforts to hide your location are probably still going to fall short. So you can use active sonar to find these things. And then blow them up with torpedoes or depth charges.
Which shouldn't be too hard, given that the ferrari of the class moves at 5 mph. And there's not even any guarantee that these things can work in shallow water. Who even knows what "shallow" is in this case? I wouldn't be surprised if their effectiveness is crippled as soon as they run into a continental shelf -- keeping them quite a good ways off-shore. It seems logical to assume that their efficiency drops off the more up-and-down cycles they have to employ, and the smaller the surface/seabed pressure differential is.
Finally, delivering nukes by sea is not a good way to get the most value from your military-industrial dollar. My understanding is that for maximum wrath-of-god effect, you'd want to blow a nuclear weapon up in the atmosphere over your target -- hence MIRV's horrible destructiveness. Ground level is not where you want to detonate. And certainly not at sub-ground level, in the middle of a gigantic heat-and-radiation absorber.
Admittedly, you are not going to save your city by keeping that nuke covered with 10 feet of water. But it's just one more strike against this as a weapon-delivery system. (Bonus Simpsons paraphrase: "Three month ocean voyage? But I'm mad now!"). A good-old fashioned cargo container would be easier to obtain, easier to retrieve, and only somewhat easier for the feds to detect.
Aqua-man has become quite the hard-ass. He cut off his own hand and grafted on a harpoon instead. He no longer takes shit from anyone. He now acts like what he is, the king of 73% of the Earth's surface. He's got armies, sea monsters, and a chip on his shoulder.
Kind of like Namor without the pretensions, and with a beard.
i'd hit it so hard, if you pulled me out you'd be the king of britain [bash.org]