Ekranoplans and ground effect

[apex1]

That is why no one has been successful at putting a wig into commercial applications. No one has yet designed a 100% stable passive WIG wing.

You know I do´nt like to contradict you, but there are several commuter services in the caribbean and I have seen at least one in the pacific region too (do not remember where), using WIG planes between islands. Another one is operating in west Alaska.
The design we have tested in the early 70´s topped FL 85 (VFR) with ease (not much for an airplane) but was definetily a WIG. And all modern WIG designs are able to climb far above groundeffect.
Naturally, to reply to some notes above, if your flight level is close to zero, colreg becomes part of the game and you have to be licensed to operate a watercraft too.
But a WIG is by definition as by law an aircraft. That naturally does not apply to a hovercraft with some very limited, groundeffect related abilities.

EDITED: a few phone calls later, and I know that I know nothing! SIC....................!

Actually there are international agreements taking place, due to a Russian intervention some years ago, to categorize Ekranoplans.

The recent international conventions are the following:

There are 4 categories of WIG craft:

HSC:>>>>>>>WIG assisted boat with water contact at all times<<<<<< IMO applies
Cat A:>>>>>WIG craft that cannot operate without ground effect at all<<<<< IMO applies
Cat B:>>>>>WIG craft with the capability to temporarily increase its flying level beyond the extent of ground effect. It cannot maintain flight without ground effect, just speed is converted into potential energy to increase height (temp.). Both IMO and ICAO apply
Cat C:>>>>>WIG plane that is capable of sustained flight without ground effect at altitudes exceeding the minimum safe altitude for an aircraft as prescribed by ICAO. only ICAO applies

A very important aspect of this recognition of the different types of WIG craft is the fact that not all WIG craft need to comply with the very strict aviation rules. So far this has never been clear. Edit end....

Regards
Richard

 

[mydauphin]

I don't mind if you contradict me. One learns by knowing that you could be wrong and growing with others knowledge and experience.

I am not familar with commercial WIGs. I see several in Jane High Speed Boats but all seem to be research vessels. All Wigs that I have heard about are basically unstable and research only. Becareful with claims of ablity to climb above ground effect, perhaps they jump out GE but they cannot maintain level flight at those altitudes. The larger the wings of the plane the higher the ground effect. I shouldn't say larger because it has to do with shape of wing. In US, wigs can fall under boats or ultralights. I believe anything that cannot fly above a certain height is not considered a plane and is not covered by FAA. I think pilots would be more worried about flying WIGS than boaters because they know that crashing on the water from 20 feet at 60mph is no joke. A wig can flip over on you like a hydroplane very easily. Anyone interested in flying a WIG, please build a model first and see if you want to be flip around at 60-100mph.

 

[apex1]

I don't mind if you contradict me. One learns by knowing that you could be wrong and growing with others knowledge and experience.

You are so right,......so right..........
And it´s not a one way road, see my edited post above!........


And I have found my recollection of the test flights mentioned above.It was 1972, near Friedrichshafen Bodensee, Germany, the Airplane was a "Lippisch X 113" built by Rheinflugzeugbau with assistance by Dornier Flugzeugbau. The most impressive fact was that this 6 seater was propelled by some 30 or 40 hp as I remember, but climbed to FL 85 manned with the pilot only.
I have found some (poor) pictures on the net, showing the plane during these days on the Bodensee.
Additionally there are two links to some further insights in Lippisch designed WIG craft. A friend pointed me to them. (surprisingly provided by a US University):

http://www.lib.iastate.edu/spcl/manuscripts/MS243/MS243.5.html

And another US publication with just one minor fault: the DFS - 194 was NOT planned to be a suicide bomb!
http://discaircraft.greyfalcon.us/LIPPISCHE AERODYNE RESEARCH.htm

Regards
Richard

 

[daiquiri]

And another US publication with just one minor fault: the DFS - 194 was NOT planned to be a suicide bomb!
http://discaircraft.greyfalcon.us/LIPPISCHE AERODYNE RESEARCH.htm

Wowwww, there are some extraordinary examples of aeronautical creativity on that page!

 

[apex1]

Wowwww, there are some extraordinary examples of aeronautical creativity on that page!

Is it too much sense of nationality to state, that Germany stands for more than,
Sauerkraut and fascism?

 

[mydauphin]

Germans have always been great at Engineering, Beer, Chocolates,
But women and food.... Well may be it was my bad experience with one...
Anyway, I said "I see several in Jane Higher Speed Boats but all seem to be research vessels." I meant to say experimental... Got my languages confused.

The problem with WIG wings is that air behaves differently at different heights from ground and speed. The basic idea is simple, the execution of a stable wing, or a self stabilizing wing is very difficult. A larger WIG would be easier to stablize than a small one. One day a large A380 size WIG could fly above the sea as a freighter, carrying more weight than a plane more economically. Computer flight controls are the only way it is going to be possible.

 

[daiquiri]

Is it too much sense of nationality to state, that Germany stands for more than Sauerkraut and fascism?

Well, I'm not really sure there's more...
I mean, if we put aside Goethe, Kant, Mann, Hesse, Leibniz, Schopenhauer, Nietzsche, Schiller, Hegel, Marx, Engels, Bach, Beethoven, Handel, Mendelssohn, Brahms, Schumann, Wagner, Strauss, Durer, all the Gothic architecture, Einstein, Diesel, Otto, Wankel, Von Braun, Planck, Leibniz, Helmholtz, Heisenberg, Schrodinger, Fahrenheit, Rontgen, Hertz, Riemann, Hilbert, Gauss, Gutenberg, Benz, inspektor Derrick, kommissar Rex, Claudia Schiffer etc. etc. etc. etc. etc. etc...
...what remains are just two miserable things you said.

 

[kroberts]

FWIW, I like the food too.

Haven't spent a lot of time with German women, so I withhold judgment there.

There is no people which has nothing good to offer to the texture of the fabric of humanity.

 

[apex1]

Thanks daiquiri,
how could I forget Kommissar Rex?
And mydauphin,
you know that the first full operational WIG was the DO X ? 1929................
Well and the German girls, at least they are not as prudish, as for example those found on your side of the pond. lol
Regards
Richard

 

[mydauphin]

One bad German or girlfriend that can't cook does not a country make. But going to back to WIGS - they have been around for a while. If you think about it a lot of the first planes like the Wright brothers flyer were really WIGS. They could not fly more than a few feet above the ground WIGS are not necessarily sea based ... They could have wheels, ski, - Therefore WIGS are not necessarily boats.... I rest my case...

 

[aztek]

hi
is this an Ekranoplane? looks more like a aeroplane to me:?: bigthough

 

[apex1]

Yes that was a WIG although Howard Hughes did´nt like that fact.

 

[kroberts]

That looks like the Goose.

If I'm not mistaken, that plane is the largest aircraft ever to fly, even today.

 

[apex1]

It is the "Spruce Goose".
But she was unable to fly out of ground effect, and today the A380 is larger.

 

[kroberts]

I have never seen any authoritative source say she could not fly out of ground effect, only that she didn't. Hughes was doing taxi tests and did not have any legal clearance to fly her at all, but knew that this was his last chance If I understand correctly, he broke several laws by going any faster than taxi speed. He got her up high enough to prove her point, and then landed her for the last time.

In other words, she "could not fly out of ground effect" for political reasons only, not for any technical issue.

Edit: There is an X-plane simulator profile for this plane which performs as designed. X-plane is a genuine simulator, where you design parts, put them together and then see how it flies. This is the software used by Scaled Composites and was used to design SpaceShipOne among others. It's probably not the best simulation software out there, but it's accurate enough for the purposes.