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Researchers To Build Underwater Airplane
coondoggie writes to tell us that DARPA seems to still be having fun with their funding and continues to aim for the "far out." The latest program, a submersible airplane, seems to have been pulled directly from science fiction. Hopefully this voyage to the bottom of the sea is of the non-permanent variety. "According to DARPA: 'The difficulty with developing such a craft come from the diametrically opposed requirements that exist for an airplane and a submarine. While the primary goal for airplane designers is to try and minimize weight, a submarine must be extremely heavy in order to submerge underwater. In addition, the flow conditions and the systems designed to control a submarine and an airplane are radically different, due to the order of magnitude difference in the densities of air and water.'"
Airplanes underwater??? This is crazy talk! Next they will wants subs that fly!
to build a flying submarine - I mean after all, if we made a brick fly (an old saying about the F-4 Phantom).
Linky
Steve Fossett's Unfinished Project
Posted by kdawson on Sunday October 05, @02:36AM
from the ocean-flying dept.
Transportation Science Technology
MazzThePianoman writes "Steve Fossett left behind a secret vessel project called the Deep Flight Challenger. Fossett was funding the development of a winged submersible being designed by Hawkes Ocean Technologies in California. The intent was for the vehicle to be capable of travel to the very bottom of the ocean -- the Mariana Trench, more than 11,000 meters beneath the surface. 'It would have dramatically, dramatically opened the oceans for exploration. It would have been a game changer,' said Graham Hawkes, the designer. Testing had been completed at Department of Defense facilities. Field testing was only four weeks away when Fossett's untimely death, a year ago, put the project on hold." Hawkes Ocean Technologies owns the design but the vehicle itself is owned by Fossett's estate.
I don't have anything to say, but everybody else is posting stuff with "Steve Fosset" as the title.
Sounds like a few too many people at DARPA liked 'The Phantom Menace' a little too much.
http://en.wikipedia.org/wiki/Image:Flying_Sub.jpg Someone's imagination is running wild. If DARPA is giving them money then it's time to turn them off.
No, this is an airplane that can also be a submarine (and surface vessel). Fossett was financing a sub that "flew" underwater.
Rocks sink, and Rocks Fly. Problem Solved!
Fossett was building a submarine that 'flew' underwater, maintaining it's boyancy but overcoming it by using forces similar to an airplane (lift, control surfaces). He was going to pull a stunt to fly to the bottom of the world (Marianas trench) for a record. The vehicle is finished.
I'm not sure, but I believe those "underwater airplanes" already exist.. and are called "submarines".
MABASPLOOM!
study up on flying fish and flying squid
then dabble in cormorants and water beetles
once again, mother nature was here first and has a lot to teach us about where to start
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Before they go too far with the designs, DARPA might want to check their figures for the densities of water and air. Last time I checked they differed by a lot more than "an order of magnitude" and I'd think this might be important.
Supercavitation would allow submarines to move at supersonic (with reference to water) speeds while submerged, and dogfight underwater like WWI aircraft did in the air. If they can come to a complete stop they'd be silent and invisible, just floating there, then fire up the engines and go back to moving faster than ship-based sonar would be able to detect them. There's already a supercavitating torpedo. People who design targets -- I mean aircraft carriers and destroyers -- must be worrying about this.
Nostalgia's not what it used to be.
How about this, a rear propulsion planwhich the pilot operates in a counterbalanced globe at the nose. The airplane slows down to a minimum airspeed and inserts the nose and flips over, the pilot's globe rights itself and the planes control surfaces are inverted. The fusalage takes on water to neutral bouyancy and the plan controls as if it were upside down. I'm sure this is completely unfeasible and I hope someone will explain why. The main problems I see are 1.) Slowing the plane enough that 'insertion' doesn't rip it apart. 2.) The pilot seizing up during this maneuver which would go against all of their piloting instincts. 3.) Control systems designed for air travel would be completely inefficient/infeasable in an aquatic environment. Did I forget anything else?
-=Bang Bang=-
I then put two and two together and got five, because I realised that the disagreement arose because the interviewer did not expect the operating temperature range of the hardware to exceed more than about 25 degrees C - which made sense if it was for use in sea water.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
"We're taking over 150 atmospheres of pressure!"
"How many atmospheres can this ship take?"
"Well, it's a spaceship, so I'd say anywhere between 0 and 1."
Eek!
I don't have anything to say either.
This was Fossett's project I believe. They already have a design and partial prototype yes?
I think they've built a prototype, yes. Unfortunately, the test of the prototype of Fossett's follow-on project, an airplane that can fly underground, ended in disaster.
Too soon?
The enemies of Democracy are
Isn't this the same exact kinda thing that Steve Fossett et-al were building (completed?)
Yep. The first test pilots were John Denver and John F. Kennedy Jr. Apparantly the tricky part is coming back up...
I'm waiting for the sonic boom.
now we need to go OSS in diesel cars
since when is "fuckofftags" a useful tag?
You gotta keep scientists off the streets and out of trouble somehow.
now we need to go OSS in diesel cars
They're saying how the requirements for submersibles and aircraft are diametrically opposed. That's good! If they were only kinda in opposite directions, that'd be a challenge. But calling on my vast electrical engineering knowledge (and what is mechanical engineering but electrical engineering with molecules instead of electrons?), I can tell you this is easy. What do you do if you discover that your current is diametrically opposed to what you want? That's right, you flip the terminals around, and bam your current is spot on!
So, using the same principle. In air you want the plane light and lift high because gravity means the natural tendency of the plane is to go downward and you want to go up. Underwater, gravity turns into buoyancy and your plane would naturally want to go up when you want it to go down. This sounds like our current problem -- we have a plane that flies perfectly in air, but in water goes the opposite direction of what we want. So what do we do? Yeah, we just flip it. Now the "lift" of the wings is pointed down. All you need then is an engine that works in air and water, and either a crew compartment that rotates to stay vertical, or sturdy straps and training for pilots to maneuver while upside-down. Done!
I just but the reversed-wing thing is actually used in some high speed submersible. Exercise on how to make it work in either direction above/below water left as an exercise for the DARPA grantee.
The enemies of Democracy are
All submarines 'fly' underwater. Take a look at the control surfaces of a submarine sometime. The cross section is similar to that of the wing of an airplane. A submarine is similar to a dirigible in that it can either adjust its ballast or use its control surfaces with a propulsion system to control its depth.
Well, i have lots to say!
I just don't feel like saying it.
-Taylor
Worldwide Military budgets: $2100 billion. Worldwide Space Exploration budgets: $38 billion. Really, world? Really?
http://www.susanscott.net/Oceanwatch2002/jan04-02.html
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
When I was in the Navy, my Captain was a submariner and my XO (2nd in command) was a helicopter pilot.
These two guys didn't get along.
In one (of many) knock down drag 'em out verbal exchanges the two had, the Captain yelled at the XO,
"There are more helicopters at the bottom of the sea then there are submarines in the sky!!"
http://www.htcherocentral.com
So, I hear the prototype airplane that flew underground, lost power and crashed into the surface?
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
I don't understand the assumption that a submarine-aircraft would have to be made heavy and thus be too heavy to fly. Therefore the idea is suggested to be not likely to work at all or will be too compromised to be good at either role.
Rather than resisting water pressure with a heavy pressure hull, it is only necessary to equalize pressure internally and externally. Also consider that humans can readily withstand pressure to a depth of 20-30 metres (just don't try surface in a hurry).
It then becomes not necessary to reinforce all but a few sensitive systems against pressure at depth. That said it's not as simple as taking a F-22 and filling the avionics full of scotch guard and drilling some drain holes. But landing say a helicopter on water, flooding it and having it perform adequately underwater is not a monumental engineering challenge.
In such a craft you could still have a small pressure vessel for crew and sensitive systems, while the rest of the vechicle is filled with ballast water and the resulting compressed air. We are still talking about weight penalties in additional systems and design, so it's still a vehicle that's neither a good aircraft nor a good submarine.
I also think Darpa would be better off with a some VTOL design considering the difficulties in taking off from water. Something like a submarine apache would be quite an achievement. I'm forgetting that the F-22 design is VTOL capable, now that would be a scary machine for any enemy to go up against.
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
Does Phantom Menace even have a flying submarine? It has a regular submarine...
But anyway, obviously the correct reference is to the submersible squadron from Sky Captain and the World of Tomorrow. Der. Plus: Angelina Jolie!
Comment of the year
The definition of flight, as I studied at flight mechanics, is the motion through a single media or lack of media. :P ), since their motion is between two media.
Airplanes fly through the air
Zeppelins and balloons fly through the air
Submarines fly through the water
Space-ships fly out of atmosphere
Ships do not fly because their motion is in between two media
Cars do not fly (except for some instants, as it is the case of Rally cars jumping
From an engineering point of view, submarines use buoyancy forces mainly besides hidrodynamic lift at controls. There are interesting projects around about small submarines using mostly hidrodynamic lift to move around. However, being buoyancy so cheap and independent of the speed of the sub, makes it so interesting for a sub. In aviation, however, in order to obtain good buoyancy you need so much volume that makes it impractical (Zeppelin) and smarter approach is required (aerodynamic lift) with a penalty (minimum speed required).
What? Oh sorry, wrong door.
I love the self-assurance of the ignorant. Quite cute, really...
I work with ex-submariners. One of the reasons that they hated and feared a real reactor SCRAM was that the sub was essentially relying on its forward motion to maintain it's depth.
Yes, it was negatively buoyant, but the slight upward pitch of its planes enabled it to "fly" through the water. Supposedly, you get much more responsive control that way, rather than wallowing in the water while you wait for tanks to fill or empty. Very important, when you're trailing an aggressive Russian sub...
When the reactor shuts down and the screw stops turning, the damn thing will sink until the control team get the tanks set for neutral or positive buoyancy. Not a comfortable time as the boat heads down and the hull groans and creaks and everyone starts to wonder if there's enough high pressure air in reserve to blow the tanks.
Mainly OT, but by God and by golly, major navies do FLY their subs.
Political language
that will fly like a lead zeppelin. What next? Roll-down windows for submarines?
Free, as in your money being freed from the confines of your account.
This type of object exists, we HAVE flying submaringes, they are called BIRDS. Diving birds are NOT constrained by their weight. Their problem is their lungs. Several spieces swim very well under water and can even go straight from flying to submerged.
If birds can do it, so can man.
The trick is to stop thinking of this object as an old fashioned submarine and accept that modern submarines FLY under water. They use their "wings" to control their movement, not their weight.
The biggest challence is re-configuring the wings. Birds can do this easily but swing-wing is out of fashion for a reason. A swing wing that can survive a dive is going to be a major piece of engineering.
Another challenge is getting from one method of propulsion to the other. Birds of course use the same engine and switch effortleslly between legs and wings for power, can humans do the same? Have a single engine that can power motion in air and underwater?
There is however one part of the requirement that might make it more difficult. I think this aircraft is intended for the insertion of seal units quickly without having to worry about air defences. For the seals to disbark from the aircraft underwater it would have to be going very slow or even be motionless. An aircraft that is light and uses negative lift to remain submerged would shoot up like a cork if it stopped.
Key problems:
Power source that can operate underwater.
Two modes of propulsion for air and water.
Switching quickly between modes and both modes not interfering with the other, for instance propellors would probabbly smash during a power dive.
Being able to remain motionless underwater and also submerged.
If it wasn't for the last requirement the trick would be fairly simple, "just" a plane that has positive lift in the air, negative lift under water, super-cavitation speeds to be able to shoot up out of the water with enough speed to remain airborne and a system to switch seamlessly between air and water propulsion.
Do-able. But remaining motionless underwater adds a whole new trick. Suddenly you can use your speed and re-use your wings to remain underwater, you need to alter your weight.
Mind you, I wonder if we at slashdot are not overcomplicating things. What DARPA is looking for is a way to insert seals with minimal detection.
What about an 'ordinary' sea plane that instead of sitting above its floaters can sink beneath them? Imagine an ordinary plane with floaters attacked sticking out the sides and below. It lands on the water as all seaplanes do but then the floaters rotate above the fuselage allowing to disappear beneath the waves. The fuselage opens, allowing sea-water inside removing most of its lift. The floaters act like miniature subs and can submerge to an extent. This aircraft is not about setting records, it has to operate near the coast anyway so can't go to deep in any case.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.