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Old Jul 25, 2010, 06:52 PM
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Hello everyone.
thinking about how to solve the problem of the extra push needed to get out of the water without a bag of hovercraft an idea occurred to me, the method is to put a small hydrofoil ekranoplan and well below the water comes out faster and the interface water is lower.
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Old Jul 26, 2010, 01:47 AM
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Hey Jorge,

The idea isn't bad, it's just that hydrofoils give you a lot of drag at those speeds needed to Take off. Especially the normal ones, these are a few I build:



Believe me, whith these normal type of hydrofoil wings, there is no way you going to get to Take off speed

After these models I build a hydrofoil with "supercavitating" foils, to see if I could go faster:


Its hard to see the actual shape of the foils on the photo, but they ar more like razors than like airfoilsl and they alow you to go múch faster.

Maybe two very small traingular shaped supercavitating foils could help, but still it adds quite some drag. Durign the years, Dr. Hanno Fischer and his team tested hydrofoils on the X-114 Lippisch WIG, and crashed because the hydrofoils caused too much drag on landing.

BTW, the guys over at technotrans also played around with hydrofoils, I don't know what the results were. Actually, they have two of these small more triangular foils like I suggested haha, still don't know if it worked well.
RC model:


Real one, look very closely:


Marijn
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Old Jul 26, 2010, 04:54 AM
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You are right that the drag is a problem but as you said the hydrofoil is small, arrow-shaped does not offer much drag, and to solve problems in the land, the hydrofoil may be placed just under the hull half centimeter the ekranolplan to brush with water to not do that nod forward as far as to dump.

if the hydrofoil was located about 5 cm in contact with water before and the pitch would be too, if in addition it is turned sideways before the wing floats touch the water, tip over completely.
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Old Jul 26, 2010, 12:04 PM
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It's "off" but I have to ask, how many models you ever built, Marijn?
You built ships, submarines, vtol/helicopters, planes, hovercrafts, WIGs... I am just amazed

My first successful scratch built rc was GM2... Before that I only flew my very first RTF plane. So I am a real beginner

Gabriel
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Old Jul 26, 2010, 12:50 PM
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Haha Gabriel, lets see, a list of only RC models would be....(and not all the models are as succesfull, some maybe very old, like there is also a tandem model in the list)

7 Hovercrafts
4 Hydrofoils
3 Lippischs WIG's
1 Tandem Wig
4 Ekranoplans
2 Submarines
5 Helicopters
2 Twin engine planes
1 seaplane
1 Ducted fan jet
1 Hotliner
3 Gliders
6 other planes
1 Ornithopter
1 Autogyro
3 Paramotors
1 Rogallo
1 Tail sitter VTOL
2 Tilt rotor VTOLs
1 Outrigger
1 Hydroplane
2 ECO boats
1 rescue pushboat

Somehow I think I am forgetting a few models.. haha so, I have build tons of models, they certainly weren't all as succesfull as the other ones, most of the times rather crude fast builds

@ Jorge, have you started building the Aircat yet?

Marijn
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Old Jul 26, 2010, 02:04 PM
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Originally Posted by hoverman View Post
@ Jorge, have you started building the Aircat yet?

Marijn
if I started, but the wire foam cutter is not very hot and very difficult to cut, so far I have only the block that makes fuselage without sanding or anything, it cost me two hours to cut and the sandpaper that I have are very thick, until they buy a better thread and fine sandpaper will not be able to finish the body wings and make the side floats.
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Old Jul 26, 2010, 04:45 PM
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Hi Guys,
I am new here and very interested in WIG crafts. I saw on previos sids the Aircat90 from the Rice Brothers. I was a few time in contact with them and they said they want to made a 1:1 size Aircat90. But now the website is gone and I get no answer from the boys. Has somebody of yours some information? Are drawings of the Aircat90 exist? Because I want to built a 1:1 WIG.

B.W. from Spain
Achim
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Old Jul 26, 2010, 05:07 PM
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Originally Posted by coast-flyer View Post
Hi Guys,
I am new here and very interested in WIG crafts. I saw on previos sids the Aircat90 from the Rice Brothers. I was a few time in contact with them and they said they want to made a 1:1 size Aircat90. But now the website is gone and I get no answer from the boys. Has somebody of yours some information? Are drawings of the Aircat90 exist? Because I want to built a 1:1 WIG.

B.W. from Spain
Achim
ey, yo tambien soy español, posiblemente hoverman tenga alguna foto, yo estoy aver si hago un aircat pero los materiales que tengo no son muy buenos.

por si te ayuda , aqui hay posteada una recopilacion dedocumentos de ekranoplanos basyante extensa: http://www.wuala.com/groundeffect/Do...ound%20effect/

esta es la mia( muy pequeña), con algunas fotos de 3 vistas del a 90 y el airfisch8 y fotos varias: http://www.wuala.com/jjjasesino/Fotos/ground%20effect

suerte¡

hoverman, a few hours ago i make a quick and improvisedmodel and i put the hydrofoils to 1 cm of the hull and worked well in the aterrizage There was not any problem as well estava not only holds the hydrofoil and detached.
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Old Jul 26, 2010, 05:08 PM
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Hello

Welcome to the forum!

On youtube i got an answer to my question 2 month ago. They still want to build a manned craft. http://www.youtube.com/comment_servl...&v=qTfFNZnyuZE

I guess you have wig models, please post photos and/or videos.

Gabriel
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Old Jul 26, 2010, 05:32 PM
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anyone can help me?
try to climb up two videos on youtube of my first ekranoplan (a failure) but they failed to climb up and canceled, some know of a better host for video?
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Old Jul 27, 2010, 01:27 AM
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Originally Posted by jjjasesino View Post
anyone can help me?
try to climb up two videos on youtube of my first ekranoplan (a failure) but they failed to climb up and canceled, some know of a better host for video?
Try http://vimeo.com/. But my experience is that youtube is the best. Some times it has upload problems, but it's more reliable than the others. I think you should try it again. Check your video parameters if it's ok for youtube.


Gabriel
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Old Jul 27, 2010, 03:04 AM
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@ jjjasesino, I am not Español, I am German, leave near Malaga.
@ RdsG, Thanks, I ' ve checked the Video, but behind "Flaircraft" are there the Rice-Brotheres behind?

Sorry I have no models yet, but I still planing one befor I start to built a 1:1 size.

Regards
Achim
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Old Jul 27, 2010, 04:29 AM
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Originally Posted by coast-flyer View Post
@ jjjasesino, I am not Español, I am German, leave near Malaga.
@ RdsG, Thanks, I ' ve checked the Video, but behind "Flaircraft" are there the Rice-Brotheres behind?

Sorry I have no models yet, but I still planing one befor I start to built a 1:1 size.

Regards
Achim
I am not sure, but I guess they are the Rice brothers since Flaircarft said that they designed the aircat. If you have a youtube account you could contact them.

You should build several free flight and RC models before you spend a lot money and time to build your manned craft. You should know how to built a plane, boat and WIG models. Then you will reconsider your plans about a manned craft since a manned craft not just bigger, but it brings on exponentially more problems. On the other hand it could be dangerous.
I am not an expert but I think if you have help, developing a manned craft could be years, perhaps a decade.
No offense, but developing and building a manned craft is a serious task.

Gabriel
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Old Jul 27, 2010, 05:35 AM
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I was working in the last 20 years with GRP special in Design & Mouldbuilding. I have a lot of experience in Car building and also in Boatbuilding.
In the moment I am working for a big company on the Maldives and they have of course a shipyard as well!
I must made the decision now what concept I want to use: FISCHER or BIXEL. I like very the concept of the 19XRW Hoverwing and also Bernd Kohlers Skimmer 2 & 4 with the wings from aluminium tubes and PVC-tarp. JÖRG's concept is not good, because it allows only a flights in calm waters at highs up to 30 or 50 cm. There is a new German company they are looking for investors, based on JÖRG's craft: http://www.wig-shuttle.de/ they provide a flight high up to 1.2 mtr. what is not possible, I mean.

Regards
Achim
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Old Jul 27, 2010, 01:06 PM
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Hey Achim,

Do you have any idea how they mean to reach this 1,2 meters? I tried the tandem in and out of Ground effect, but I was able to make it stable for only one mode at a time, not making a Ground effect Tandem craft which flies up to half it's wingspan without losing stability

I guess if you want your 1:1 craft to be really safe, you'll have to go with BIXEl, as it's incredibly reliable. On the other side, the Lippisch crafts are able to fly a lot slower and show more efficiency.

BTW for all WIG enthousiasts, Graham Taylor updated his site, have a look:
http://www.grahamktaylor.com/models/...%20models.html

Greetz,

Marijn
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