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Ground Effect Flying Boat
Stalke writes "A company called Flightship has produced the worlds first commercial flying boat that operates on the principle of ground-effect. I first saw these types of craft on TLC when they showed a huge soviet landing craft based upon the same principle. The first commercial version of this craft has a capacity of only 6 passengers, but a larger version called the Dragon Clipper will seat 40! Check out the videos on the site, this thing really is a sight to see."
flightship.net/technology has information on how this thing works...
Any additional info on why it works would be good to read.
What is ground effect, you ask? Karma Whore to the rescue!
From the company (might be slashdotted sooner or later)
A good site
More info, no pics.
There have been WIGs for 'comercial sale', on a per customer design and build scale. Some companies such as Airfoil have standard designs for airfoil types and construct them for sale.
At the moment Flightship dont apear to be offering anything for imediate sale. And you have to register with them just to get a sales inquiry aplication form.
At the moment, I'm going to class Flightship as intresting vapourware.
Here's a good site on how the ground effect works: Ground Effect
(they have been used to go over land as well - deserts or anywhere large and relativly flat.)
I do wonder about the site though it does seem odd to have comments like ...Since the current tends to drag scuba divers at the end of the dive out to the open water, each team should take along a parachute. It is only in this manner that the crew of the boat can be certain of finding lost divers.
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now to me that doesn't sound to promotional. Elaine R.
Check out this site for more info. I've also seen Discovery shows about this.
I heard of this kind of thing many years ago.
The Soviets were way ahead of the game in this area as long ago as the 60's, they were called Caspian Sea Monsters because they were tested in the Caspian Sea, and looked like neither plane, nor boat.
This web site has a very nice detailed article complete with many photos.
They were quite the strange beasties back then, heres another look at them.
And heres the WIG site (WIG is an abbreviation of Wing In Ground-effect), which is also a nice comprehensive resource about these interesting vehicles.
The model maker Revell even made a plastic model kit of one, some years ago.
Apparently, this type of aircraft hasn't found it's commercial niche yet, but it looks like this new application might work.
If it don't GO... chrome it. ~ Frank Banks
> Also maybe the flying boats can be made to fly higher to skip over things that are in the way.
:)
The point of this 'flying boat' is that it operates in ground effect, which allows the craft to produce more lift than it would normally be able. If you are going to give the craft enough power/lift to climb out of ground effect to "skip over things", you kind of defeat the whole point of the craft. It is more efficient for aircraft to fly at higher altitudes, air is less dense, and fuel burn is much less, and you can take advantage of winds aloft. Operating a long haul aircraft just above ground effect is probably the least efficient may to run, least range and greatest fuel burn, not to mention you cant go all that fast. As an example of that, take a theoritcal passenger jet. Aircraft measure speed in "Indicated Airspeed", which is the relative wind the skin of the aircraft is experiencing. At sea level, indicated and true airspeeds are about the same. Now take our jet, it has a Vne (Never exceed velocity) of 330 kts. So at sea level, (negating wind), i can only make around 300ish kts groundspeed (and only over sea, in the US below 18,000 ft, you cannot exceed 250 kts). Not bad you say? Consider that at altitude, you can operate an aircraft below the 330 kt limit, but because the less dense air (less wind == less indicated airspeed), your actual groundspeed can be 500 kts, and you are getting better fuel economy.
These ground effect craft will probably due well for short haul stuff, but with the unpredictable nature of the ocean, i dont see them gaining wide use for trans oceanic operations. Much safer and efficient to be flying at FL330
Short overview of ekranoplan creation and development
There is one of these that operates on Narrahgansett Bay, where I live in Rhode Island. I should say, operated, because last summer it hit a wave and crashed. The pilot and passenger were bruised, but OK - the Coast Guard managed to pull them out before the thing sank.
Ground effect craft are not new. They've been around for decades. The primaraly work by traping air underneath the "wing" and using that to create lift. As a result, they cannot "fly" very far off the ground. The FAA ruled quite a while ago that a craft that has to stay in "ground effect" to create lift is not an aircraft and thus isn't regulated by them. A hovercraft actually falls in the same catagory because it to flys in ground effect, it just does it in a completely different way.
There is nothing inherently safe about liberty. That's why so many people died protecting it.
What's sad about the Soviet WIG program was the fact these vehicles were perfect for fast movements across the Baltic Sea to invade the Scandinavian Peninsula. Imagine moving an amphibious strike force at several times the speed of even hovercraft.
Unfortunately, the designers of the Ekranoplan were too closely tied to Khruschev (sp?), and when Brenzhnev took over, the Ekranoplan idea died a quick and untimely death.
With the application of modern technology, an ekranoplan could be perfect for island-hopping operations in the Less Antillies in the Caribbean Sea.
Yep up until a few years ago channel hovercraft were regulated by the civil aviation people, but they eventually saw sense & now they are regulated by the maritime authority.
Scroll down to Freak waves.
The fundamental issue is this. The vehicle has to be close to the water. As a result, running into a single large wave is a problem. The larger the vehicle is, the larger a wave it can handle. But the larger the vehicle is, the more it costs to build and the more it needs to transport to be profitable.
So you need quiet water which a lot of people want to cross fast. But the water has to be a lot quieter than you think. You see every so often several different waves of different frequencies fall into sync, and form one really large wave. This may only happen to you once per year, but even once per year is far too often if it happens under a vehicle that you needs several years to pay off.
So you make a bigger craft. Fine, but now it is going to take you even longer to pay off. There is no practical limit to the size of a freak wave. Bigger ones happen more rarely, but they still happen.
As a result this kind of vehicle, which by nature needs to be very delicate and very expensive, has always wound up on the wrong side of the cost curve. People have looked into them in several markets, but they are just too easy to sink in a freak accident to be commercially viable.
Of course regular ships run into these, and occasionally sink from them as well. But they don't need to be so light, nor do they hit waves as fast, and therefore ships cost less and can take more wave. this makes the risk acceptably small.
Here is a WIG (wing in ground effect) craft built by a hovercraft hobbyist. It sure looks like a lot of fun. Also, I found out a while back that the FAA doesn't regulate WIG craft, so you don't need a pilots license as long as it can only fly in ground effect and not as a regular aircraft.
Actually a WIG has LOUSY glide ratio.
First off, IAAAE - I am an Aero Engineer. Glide ratio is largely a function of the wing's efficiency - and that is almost entirely a function of the ratio of wingspan to wing "chord" - in otherwords, the ratio of width to length of the wing. (Ever wonder why a sailplane has such long thin wings?) But to get a good ground effect, you need a short stubby wing, not a long thin one - you need a longer surface to "trap" the cushion of air underneath. So wing efficiency and ground effect are actually mutually exclusive. That's the main reason that you cannot get far off the ground in a WIG vehicle. The ONLY reason it gets up is the ground effect - you simply don't have enough lift otherwise. (You can zoom for brief distances, but there is so much drag due to the lousy efficiency that you cannot sustain high flight.)
So if you remember that glide ratio is related to wing efficiency, and that wing efficiency is awful in a WIG, you get a lousy glide ratio in these things.
But as "mpe" mentions, you can easily settle down on the water and slow down to become a boat.
One other interesting fact about these things is worth mentioning. If you see the pics of the Russian monster WIG (sometimes called the "Caspian Sea Monster", due to its extreme size), you'll notice the engines at the FRONT, up high on a winglike structure. Why? Well, to get "airborne", you have to get up to speed. But water drag is so high, and the plane is so big, that they cannot simply accelerate up to flying speed. So the only way to get enough air under the wings to get out of the water is to blow it directly there - so they mount the engines in front of the wing, so that the airstream can be directed under the wing to boost the plane off the water at a relatively low speed - after which they can start really accelerating.
--Brandon / Split Infinity Music