I wonder what sort of licence you would need?
http://www.dump.com/2010/12/21/did-you- ... oft-video/

Up here and in USA these are considered boats and I think it's the same in most parts of the world, I have played around with them but they can be dangerous, I found this out by putting one upside down into trees at about 80 knots while traveling down wind , lessons learned, they are not good in high wind conditions unless you have lots of room and when oil and fuel gets on a hot exhaust system it is best to get out of the craft or the results could be worse than a bad sunburn.
Norm

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My long time neighbor was the test pilot of a similar aircraft developed in the Boston area some years ago. He spent 2 years on his deathbed when he lost control (went airborne 350 feet ) His engineer remained conscious and pulled him out of the wreckage.

The concept itself works just fine , providing it remains in ground effect , but not as easy as it appears .... it is tantamount to flying a fixed wing 3 feet above the waves at 100 mph , try that for a couple of hours and you would be exchanging it for a 60 mph boat

For all practical purposes they accomplish one purpose , they are registered as marine craft which cost 20% of what aircraft would cost. But in reality they are amphibious aircraft flying at very low altitude

They try to design them so they do not go higher than ground effect , which is fine if no load is being carried , But put 6 passengers in it and it wont lift off. So they build in extra lift which can make them go airborne and then they crash.

I like to describe it the redneck way .... they told the FAA it was a boat that skims the waves and the FAA believed it ....

. Like I said the concept is good , but the practicality is not , nature provides a very narrow window where winds , waves , temperature , and lift are perfect . The rest of the time is harry and scary and paying passengers avoid such things. That is the part they do not tell you at the investor meetings.

To me, the most dangerous situation for a flying machine to be in is at high speed, close to the ground..... so, although I like the idea, I think it is just too dangerous to be so close to the water at relatively high speed.... I would prefer if it flew at 30-50' off the water.... at least you would have a chance of reacting to something.... imagine shooting along in that and a whale decides to breech right then..... or some dolphins decide to start jumping about? .... even a freak wave?

As you know Tim, in a sea plane/gyro on floats has to be registered as a boat (a vessel that can exceed 6 Kts) and an aircraft.... so to me... to fly one of those, it would need to be registered as a boat, a plane... and the pilot registered as a loonatick

While I had one bad experience I think that there is a way to make a safe craft, I am building another one that is supposed to have all the problem areas designed out so it should be a safe fun machine to use, I assume the machine that went up 350 feet and returned to the surface in a less than graceful manner had some type of control problem which could happen to any kind of machine, I have found that it is possible to get a wig craft up high by doing a series of rollercoster climbs and dives to get extra speed you can't stay up there so you need to be sure that when you come back down you are over something smooth like water or ice or a big field with no tall obstacles.
Norm

PICTURES Norm PICTURES

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The same problems can plague race boats as well

A tunnel boat is also a ground effects machine , only the propeller is in the water and the boat itself is 12" off the surface.

They sometimes go airborne too .

A slight amount of porpoising .... catch a little too much air , and up she goes

The thing that doesn't impress me with that low flying thing, is if you watch the pilot/driver? he is sooooo busy

We all know how when landing a spam can.... at the last minute just before touch down, the yolk movements get a bit bigger.... you have to pay attention

To me, the flying boat thingy looks 'very tiring' to fly? and if the pilot were to take his mind off the job for a second, it might be all over real quick?

I would prefer it flew at 100' myself.... or, work out the height of the biggest ships funnels or yachts masts, add 10' and make it fly at that altitude.... that way none slam into the sides of tankers in the night.

I really only see disadvantages in that flying boat... sure it would be nice in the Bahamas on fine days.... but what about the rest of the world? What about in shit weather and squalls? What about in fog? what about at night? Sur, most boats have lights.... but what about if it is flying along at 80 KTS a yard off the water.... at dusk.... and there is a couple of kayakers or stand up paddle boarders who have been caught out and arriving late, in dim light? Can you imagine what that would do to a stand up paddle boarder? someone on a jet ski? or if a whale did happen to breech at just the wrong moment?

Pass.... I don't like it

The one I was referring too used a small inboard with a leg and prop for around the docks and slow maneuvering , nice and quiet , very maneuverable and safe

It used the boat propeller up to 30mph and then transitioned to a lycoming engine & prop mounted behind the cabin. Once they had enough lift they raised the boat prop up into the hull

They had a methodical test plan and only increased speed in 5 mph increments over many weeks and everything went smooth until one day they were lightly loaded , over 100 mph , hit a gust of wind or something and started climbing. He flew it like a plane at first but then it came straight down. The pilot was knocked out and couldnt remembered any of it . The engineer was OK and they had a chase boat following to pull them out of the water.

On 'voyage to the bottom of the sea' they used to do that in the flying sub all the time?

If they are not designed correctly they will try to nose over when you get close to the surface and that will require extreme care to fly and is not much fun but when set up properly the closer to the surface the more nose up they get without any help from the driver, even if one wingtip hits the water with a correctly designed tip nothing bad happens, it will start a tip walking that slows it down quickly, the only real danger is in high winds where you can get picked up and flipped over or blown off track in a narrow river and hit trees or other things that will ruin your day and possibly recycle you into worm food.
Norm

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When you watch the race-boats go airborne you can see they gain altitude very quickly in the first few feet .... but because they still have prop thrust down in the water it keeps pushing the nose up until they go inverted .

When the WIG goes airborne it has the same (high) rate of climb but still has aircraft propeller thrust so it keeps flying and gaining altitude for a few seconds .... remember it launched with a high angle of attack . The natural reaction of the pilot is to level off and "fly" it back down ... but that same high angle of attack bleeds off airspeed and it becomes a stall and splat .

Pulling power immediately at liftoff only means a stall and splat from 30-50 feet instead of 100-300 feet and it hurts just as much. It would be very easy to design ailerons and elevators so that you could safely "fly it back " to the surface , but by then you are in the aircraft category and not the marine category which defeats the original purpose of hauling passengers fast and cheap over stretches of water.

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A one or two place true ground effects wing works just fine but you cannot haul very much and it should only be flown just above stall speed and then the tunnel-hull boats will pass you all day long.

To haul freight or passengers you need more wing and more airspeed and you end up with a low flying "almost airplane" by the time everything is working properly.

The investment attraction of WIG was always to transport people as fast as a small plane but within the low cost boat category . Trouble is you end up in no-mans-land where it is both a plane and a boat ... yet neither a plane or a boat.

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We built a 13 passenger hovercraft that had lots of surplus horsepower and thrust but it would outrun the air cushion at 70 mph and the front begin to settle in the water .

We considered a canard wing out front would have provided lift , but as speed increased the pilot would end up having to fly the canard wing precisely and split-second by split-second . If the nose was allowed to drop the whole machine would plow nose first into the water . If the canard wing lifted too much , the air cushion under the machine would be lost and it would mush tail-down into the water.

It would be like flying an airplane with the elevator way out front , it can be done but you need reflexes like a cat and things can go wrong quickly. A high speed WIG needs the same intense control inputs by the operator .... trying to keep it out of the air and out of the water at 100 plus mph .... it can be done and hopefully they can design a wing that is self stabilizing by using ground effect alone.

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Don't hear much about hydrofoils anymore , they were popular back in the 1970s



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yeah, Sydney Australia was famous for its hydrofoils.... they only retired them in the late 90's. They were good, fast ferry service... they take alot of power to get on the foils, but once there, they can cruise fast with little power (for the speed). I believe they got retired because the harbour got too congested for them to be safe.... and now everyone drives cars, there is extra lanes on the harbour bridge and a tunnel under the harbour.....

they were pretty exciting to ride on

A correctly designed wig craft will not zoom to three hundred feet and they cannot stall, a properly designed hovercraft with a good vpr system will not plow in but at high speed it can blow over backward and ruin your day. If the engine quits at high speed it will flip over backward if the speed is high enough.
Norm

I like a hovercraft with wings and two fans; one fan for forward thrust and one fan for downward lifting thrust, for when the wing isn't going fast enough to lift.
I would want a deeper skirt than this one has though.....

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Norm (or anybody) I could dig up my old engineering PDF links and articles on WIG if you want. Some of it is very technical but good for a designer . Some magazine articles are informative too

A designer from Finland teamed up with a designer in Germany years ago and began "perfecting" WIG .... around 1989 some prototypes were going thru trials in Florida and then Bill Russel in Connecticut purchased licensing rights and started experimenting ... it was one of his models that went airborne and splat ... he made some unauthorized "improvements" which violated his contracts and I think he quit.

Now Australia is having some success reviving it (Opening post) . All these models are birthed from the original 1980's design under various names . The craft is good , the issue has always been keeping it flying in the sweet spot between the water and sky.

Let me know and I can look them up and post the links.

That looks like alot of fun I want one

I think a deeper skirt would cause too much drag? Maybe a retractable skirt? (I want to get my girlfriend one of those)