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Japanese Researchers Test Flying Trains
An anonymous reader writes "As an alternative to maglev trains, Japanese researchers are working on ground-effect vehicles. A ground-effect vehicle takes advantage of fast-moving air and uses some stubby little wings to fly just above the ground, like a maglev without the mag. This is a tricky thing to do, since you have to control the vehicle more like an airplane than a train: you have to deal with pitch, roll, and yaw and not just the throttle. A Japanese research group has built a robotic prototype of a free flying ground-effect vehicle that they're using to test an autonomous three axis stabilization system."
No tracks.
I, uh, hmm. Okay. In Bizarro World, do they also have Submarine Cars and Space Boats?
There's a spot in User Info for World of Warcraft account names? Really?
Where we're going, we don't need tracks.
This one needs a wing span space, not as thin as current trains. But if this design saves a lot of energy, why the heck not. This is really like a low flying airplane which sounds like a cool idea.
the view would totally suck
For justice, we must go to Don Corleone
As cool as this idea sounds, is it really a reliable mode of conveyance? I envision this causing more problems than it hopes to solve. Actually, what problem is this solving? The fact that our trains don't fly yet?
...will you be able to do a barrel roll?
So if you look at the article, doing it this way does NOT eliminate the track. There's still a complex track that the train runs in - that U shaped concrete trough that you can look at in TFA. The walls of the trough prevent gusts of wind from shoving the train around. The control system would have to be extremely precise, and able to react very quickly to events like a big gust of wind. I would guess the 'train' car has wheels.
Advantages - the track doesn't have coils or magnets in it. But one glance reveals that it's still an extremely expensive, complex effort to build the track - probably millions of dollars per mile.
Disadvantages : in every respect, it's still a high speed train. The ground effect trick is to achieve faster speeds without magnets, that's all. If you board one of these, you have to be going to a specific destination all the other riders are going to. Every stop slows it all down. Most of the time you save on one of these you lose due to waiting to board the train, walking to the train, etc. And you're crowded in with the public.
And while you eliminate the need for coils in the track, you have to use even MORE concrete and steel to make the cage visible in TFA, and you now need an extremely high performance control system in the train that needs to work for the train to not crash.
In short, it's a terrible idea. What we need are cheap robotically controlled cars that run on a switching network that go from starting point directly to individual destination. These cars don't even need to be all that fast, and could use conventional technology (except perhaps using capacitor banks and frequent charging points or something...but conventional tires, road, etc...we'd use the road network we already have and install fencing and barricades and bridges so no pedestrians can ever enter the streets)
It would fly over it or you'd punch a hole in the thin aluminum fuselage of the traincraft.
Okay then. Make it carry 1500 people and operate it in urban areas as rapid transport and you'll have one-upped these guys.
But wouldn't the money be better invested if they designed trains that can swim instead of trains that can fly?
Seven puppies were harmed during the making of this post.
Just add those wings to the conventional maglevs, it would reduce it's weight in high speeds and it's energy consumption.
This story is missing the Canada tag. Because, you know, this story is about trains and Canada has trains.
Its not too often you see researchers combine technologies and come up with less than the sum of their equal parts. Imagine, a transport that can crash AND derail. Woo!
Nobodies Prefect
Tidbits for Techs Technology Blog
This might be a good idea, if they can figure out how to supply electricity to power the flying train. Tricky, because there is no ground contact, unlike a regular train, and the track itself does not propel it forward, like a maglev track does. Otherwise it has to carry its fuel, which might negate the advantages of the idea.
Heck yeah! I've been waiting for decent hover technology for years. Back To The Future 3 predicted correctly!
tried floating trains, but that didn't work so well...
This is clearly a derivative of an old Soviet vehicle. They never got much use of of them because they require a perfectly flat surface in order to work properly, hence the Japanese building a specially made track for it.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
But the conductor on the flying train in a black foggy alien and the passengers are a tall blonde mysterious woman and a street urchin?
Don't these "researchers" have anything better to do than watch Back to the Future, Part III? I mean really - a flying train... Give me a break!
In the graphic showing the concept for the final vehicle, the train appears to use jet engines. Is this really how you would do it? I thought that jets were pretty much dreadfully inefficient unless operated at altitude.
Then it will really mean it, when someone says: I'll ride the tube ;-) ( greetings to London )
Ground effect principle really works best for flat surfaces like over the water, similar to a hovercraft it creates a pocket of air beneath it, but instead of using a skirt, it flies by the forward movement forcing air under the craft and its low position to ground preventing it from escaping out the side.Ground effect only works (an extra 50% lift compared to normal wings at a higher altitude) at half of your wingspan above the ground so in order to clear a small hill of say 5 meters you need a wing span 10 meters long; may as well finish the job and build a plane (however you would be getting good fuel economy if you kept it that close to the ground). So cars aren't a good candidate for a ground effect vehicle but a boat flying over small waves or a train traveling a fairly flat route are good options.
Rocket Surgeon.
Russians have been playing with huge ground-effect transports, Ekranoplans, since what - the 1960's? There's plenty of WIG (Wing In Ground effect) boats around. Hardly new stuff that needs a lot of research.
The power to build the air cushion beneath and on the sides can be produced converted within the craft in contrast to the old pneumatic tube model.
The air for the cushion will be sucked in on the front, reducing the drag.
The technology of electric pickups for high speed trains is there.
I think the construction cost for a length of big tube is less than for a Maglev track!
The power to build the air cushion beneath and on the sides can be produced converted within the craft in contrast to the old pneumatic tube model.
The air for the cushion will be sucked in on the front, reducing the drag.
The technology of electric pickups for high speed trains is there.
I think the construction cost for a length of big tube is less than for a Maglev track!
Honest question: What benefits would this have over mag-lev?
...works best for flat surfaces like over the water...
Well, if you actually knew about water you would know that, on this planet, it isn't really flat. The only spot you will find flat water surfaces is on lakes (which accounts for about 10% of global water surface). The turbulences of the open seas + turbulences in air pressure created even by the smallest wave movements, when something is moving above them very fast, make using ground effect notoriously difficult since the under-body has to sustain very heavy punishment in case of actual grounding.
This is why there is no such thing as small or medium ground effect transport on land or sea since for smaller objects you have to be too close to the ground to generate the effect in the first place leaving no space for surface deviations (or small pebbles for that matter).
This is why there are no ground effect super freighters either because the bigger you build them the harder they fall.
ground effect sounds nice but if I'm going to dream about a form of transportation that is purely academical I'd choose ftl or mater through data relay ;-)
-- no sig today
On another note I should have read the whole post!
-- no sig today
The only spot you will find flat water surfaces is on lakes (which accounts for about 10% of global water surface).
- I think you WAY overestimate the amount of non-ocean water on this planet.
You can't handle the truth.
Ekranoplanes don't need perfectly flat surfaces- they were tested and ran mostly on water. Water is not perfectly flat yet the ekranoplanes ran....
It looks like a geek toy to me. At least as train, such a vehicle would not be very practical. The main problems of todays train systems is not speed, but how many people can be moved and how can cargo be distributed more efficiently. The first thing involves two deck trains, trains without locomotive (which follow more or less the concept of a tram). The second thing has to do with shorter or easier to decompose cargo trains. So they can transfer containers from the harbors to the interior.
But cool device.
http://www.youtube.com/watch?v=IgtaeRZjWNc
The Russians mastered the use of ground effect to fly 500 ton aircraft over the sea, beneath the radar. The ekranoplan was reaching speeds of 400 mph over sea in the middle of the last century. This is not even new technology. The Swedes were making them before the last war.
I love stacking my barbecues in the shed at the end of summer - you can't beat a bit of grill on grill action.
http://www.youtube.com/watch?v=IgtaeRZjWNc [youtube.com]
The Russians mastered the use of ground effect to fly 500 ton aircraft over the sea, beneath the radar. The ekranoplan was reaching speeds of 400 mph over sea in the middle of the last century. This is not even new technology. The Swedes were making them before the last war.
I love stacking my barbecues in the shed at the end of summer - you can't beat a bit of grill on grill action.
Surely you mean Galaxy Express 999, considering the
Granted, both are created by Leiji Matsumoto, so it is understandable that one could get confused.
Mit der Dummheit kämpfen Götter selbst vergebens
Looks like it will wobble badly with any stray gust of wind. OK for cargo, but the important question is wether you are airsick, motion sick, or even seasick.
Am I the only person who read this and remembered the old Heinlein juvie "Starman Jones"? I loved that book.
-I think you are right
-- no sig today
A car train weighs from 1e5 to 3e5 pounds. At the low end two passenger cars weigh as much as a loaded 737-300ER, which flies for some time because it climbs where the air is thin, has a ginormous wingspan and makes a lot of noise. Landing it in crosswinds is fun enough. I'd really like to see a train made of, say, ten passenger cars (cargo cars are left as an exercise for the queer reader with an engineering eye), weighing anywhere from a million to three million pounds, negotiate a turn with 'TeH WinGleTS' (TM) at 180 mph and 10 inches altitude above ground.
At the very least, maybe if Miyazaki-san is reading this we can have an expansion to some leijiverse arc which, frankly, are more needed than stupid news.
And you really think that because it can hover a bit when the sun is out and its doing 400mph it has to be versatile enough to be adopted as a serious form of transport? Yes it was useful in WW2 but hey the sr71 was useful in the cold war and I don't jet around in scramjets, do you?
-- no sig today
I thought the problem with ground effect super freighters was that it was very hard to land them in anything other than water, and once you'd landed them in water you had to expend so much energy getting them back out that in the end it wasn't really worth it.
" do they also have ... Space Boats?"
They have spaceships so I guess, yes.
It's not a trainrobbery, it's a scientific experiment.
Or wait till the next natural disaster happens, when you'd have to rebuild anyway.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
They had to use rockets to force enough air under the wings of the big ekranoplanes just to get them out of the water.
Rocket Surgeon.
It's more like a grounded-airplane, or plane-on-a-rail.
mag-lev is mag-lev not only because it use mag to keep things on rail, but it's the propulsion source. Now that "train" thing is going to use turbo fan engine as the propulsion source, not wheel nor mag. So...hey it's really an airplane
Once you have the train sitting in a trough, why not use an air cushion to push up rather than a wing pull up? The air cushion exists in the trough where there is no wind. The train could provide the cushion on its own power or the track could carry compressed air in a pipe and deliver it under the train through a network of valves. You would need a low friction moving seal along the length of train but it doesn't need to be great. Make the seal interface float on magnets if you want. It would carry a small fraction of the force of the whole train's weight.
The amazing Howard Hughes invented WiG in 1947 , he just didn't realize it.
And he did it with a plane made out of wood , like some sort of super caveman.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
I disagree with the posters comment that a ground-effect vehicle is inherently more difficult to control than a MagLev train. A MagLev train utilizes magnetic bearings to compensate its weight. There are two separate MagLev concepts. The Siemens MagLev utilizes attractive magnets in order to compensate the weight of the train and maintain frictionless motion along the track. Magnet force is nonlinearly inversely proportional to the gap between the anchor and the stator. That means by a disturbance in position, the forces will increase in the opposite direction of that disturbance. A magnetic bearing has inverse stiffness and requires an active control system in order to maintain a constant operating point. The alternative concept for a MagLev was developed in Japan utilizes attractive magnets, but requires wheels at low speed to operate. It also requires an active control system in order to maintain its desired operating point. It is actually mathematically impossible to design a magnetic bearing system that is stable in all six degrees of freedom. An active control system is always required.
A ground effect vehicle on the other hand can be designed to be aerodynamically stable because as the air gap decreases, the air pressure within that gap increases. It would work along some of the same principles of operation of an air bearing.
The design of an actively-controled magnetic bearing system is non-trivial. Designing an effective control system which can maintain a desired operating point with measurement noise, external disturbances, etc. is also non-trivial. I think developing a MagLev train is inherently a much more difficult engineering problem to solve than designing a ground effect vehicle.
While quickly scanning the headlines, I first read this as "Japanese Restaurants Test Flying Trains"
*Sniff* I always wanted to try airborne sushi...oh well, maybe next time.
"I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
How fast can you stop a train that is flying.
Pretty fast if you can actuate some flaps to dump the lift and set the thing down on rubber tires or skids.
Have gnu, will travel.
This one needs a wing span space
It seems to me that the obvious solution would be to pump compressed air under the train. That way the track could be just as wide as the train is, like any normal railroad.
Power could be transfered using an overhead catenary cable plus a return conductor under the train. Perhaps this conductor could also be used to make a linear induction motor, with less losses than propellers.
http://www.pbfcomics.com/?cid=PBF048-Suicide_Train.gif
"these guys" haven't achieved your example yet either.
Gravity Control, the stuff that is used by the Flying Saucer, does it without noise. These spheres under a Saucer can lift a 10 or 100 ton vehicle off the ground with an an-ordinate small amount of power. After I got the patent on the technology, I offered it to Nasa, so that it could be used for the Shuttles. They would not need Rockets anymore but could fly to the ISS in one hour, the Moon in a couple of hours and to Mars within one day. Nasa rejected it , it would make the Heavy Lifter obsolete. If I can get the funding, I can build a small flying craft that can fly a few feet off the ground (up to 30 feet, otherwise you need a Pilot's Licence.). Future "cars" will use it too . Real off-roading is possible., you do not need roads. The Forcefield that the technology brings, will make collisions almost impossible. Although eventually you might get the system of power tapping out of the aether, that a Flying Saucer uses and was used by Tesla for his Pierce Arrow Car in 1931, for now you can use some batteries and a small power generator when the batteries are low. I found hundreds of applications for the technology, from Power Generation, to ING, Tornado busting and Earthquake retarding. Power at 1 cent per Kilowatt or less, making Nuclear, Wind, Water and Solar obsolete. Regards, Joe Hiddink