Wing In Ground-effect craft

[El-Kablooey]

I have thought often about this, Bruno. Not racing exactly, but building an inexpensive light, but strong and safe airframe. I don't think it would be terribly difficult. I think you could build molds from plywood easily, and make your wings and fuselage from aluminum (or even wood) spars and ribs, carbon fiber & epoxy covering, then fill all the airspace in between with expanding foam (this stuff is alot stronger and harder than you might think). If you kept the plane very small, like BD-5 sized you might even keep the wieght low enough to qualify as ultralight. Of course I have oversimplified the idea to an extreme because I don't feel like typing for an hour. I think you could come out with a very light, strong and safe machine after you used the first 2 planes built for destructive testing. I also think it would be very, very inexpensive for an aircraft of any kind, especially if you kept your instrumentation minimal, wouldn't be making any very long flights anyway. The ballistic parachute would likely be more expensive than the entire plane (not counting man-hours). Aluminum could be scrapped from retired hang-gliders, and inspected religously. Hang-gliding is a very popular sport in my area, within 1 hour of here there are at least 20 ramps, some of them providing some world class flying, making it very easy to find old gliders that are in fine shape, just considered obsolete for very very cheap. My dad sold one of his old gliders a few years back for $150, it was quite airworthy even though it had been made in the early '80s.


I know you guys are gonna have a heyday with this, and feel free to. Alot of people are over-pessimistic and weighed down by conventional thinking.


I am currently building a little hydroplane boat, gonna push it with 100+ lbs of pulsejet thrust. The boat + me + PJ's + 40lbs fuel + starting battery will all total up to less than 350lbs. The idea of putting some chopped wings and a tail on it will not leave my mind. It would be sooo easy to make into a wig. The boat practically flies without wings, just skipping like a stone only touching the water for a moment and spending the majority of its time riding on the outboard engine's cavitation plate. The only thing really keeping one from lift off is the cavitation plate and the fact that when you leave the water the outboard becomes ineffective.
Go check out the beast at http://www.universalhovercraft.com that thing weighs 844lbs empty, and from what I can tell by thier specs the wings are under 8' long, total span of like 21 feet with 7' or so of that being the cockpit area. I don't want to be able to leave ground-effect flight, and I don't think flying 4'-6' above the water could be any more dangerous than hauling-butt in a regular hydroplane of the same make, actually it would be slightly safer considering no possiblility of hitting a stump or other obstruction just under the surface. Pylon racing WIGs would be interesting to say the least, not to mention fun as hell and alot less hazardous than actual airplanes.



Ok, let me have it guys , I am begging for it here! ;)

[Bruno Ogorelec]

Pylon racing WIGs would be interesting to say the least, not to mention fun as hell and alot less hazardous than actual airplanes.

Ohmigod... you are right. Pulsejet powered WIG racers... why haven't I thought about that? The mind boggles...

[El-Kablooey]

I'm thinking I might have one soon! I could use some help from some of you designing the parts to add on to my little boat. Anyone?

[Anders Troberg]

I don't actually have anything to add, but as an oddball engineering junkie I've always found WIGs fascinating. I've thought about pulsejets for them, although mainly as extra power during takeoff. Since they are light, they would not be a burden during flight.

The biggest design problem I see is how to keep the wings as close to the surface as possible, without the wingtips snagging the surface when turning. My best ideas so far has been along the lines of designing the controls and control surfaces in such a way that you get some up rudder when turning, thus gaining some height. This is also good for tight turns, as it can be used to bleed off some speed.

Go for it, and keep us informed. Post whatever ideas you have and I'm sure we can assist in refining them.

Jast make sure you keep the plans, because I will want one. Skimming low, fast and loud over the water must be one hell of a ride!

[El-Kablooey]

go watch the video at the link I posted above, he drags his wingtips in the water during a turn with no ill effects. I would weigh less than 1/3 of that hovercraft/wig thing, so I guess I would only require 1/3 of the lift. Look at the specs for it, it has a wing span of approx 22' ( I can't remember exactly) the center cockpit section is approx 7', leaving 7'6" for each wing, I shouldn't need that much. Help me out here guys, could I get away with a 4' wing on each side? I have to run right now, but I will post the plans for the boat later today. I'll start a new topic in the off topic forum.

[steve]

if you want to keep the tips out of the water just give the wing a bit of dihedral (but not so much that the tips are out of ground effect!)

[El-Kablooey]

Ohmigod... you are right.

Strange, Bruno, but even I find that statement a bit unsettling. ;)

[Anders Troberg]

go watch the video at the link I posted above, he drags his wingtips in the water during a turn with no ill effects.

When there is no waves, I'm sure it will work fine. I'm not as sure that it will work as good when the water looks like water usually does. If it is run over flat ground it is definately bad.

Does anyone know if the craft in the video floats, should an engine fail?

How about a honking big hinge in the middle, so you can fold the low wing up? First ornithopter WIG!

Nah, doubt it will work. It will just tip the thing over.

if you want to keep the tips out of the water just give the wing a bit of dihedral (but not so much that the tips are out of ground effect!)

Thought about that, but it seemed like cheating. The ground effect is stronger the lower you get, so the lower you can get the wings the neater the construction.

[El-Kablooey]

Yes, the craft floats,on air, it is a hovercraft actually. It is a hovercraft that you can convert to a WIG craft by bolting on the extra hardware. Surely it floats if the engine fails, It is made of foam and plywood. It is extremely heavy in my opinion though, but surely it will float.


I don't know of any lakes, except for the Great Lakes up near the Canadian border that ever have waves, even in a storm. I imagine you are speaking about the ocean. America is absolutely covered with pretty large lakes, and almost every navigable waterway in the U.S. isn't owned by anyone and open to public recreation.


I don't think dragging wing tips will be a big problem for me, especially once I learn to control the thing well. I will be alot lighter, have shorter wings, and maybe able to fly a little higher. I think as long as your wingtips were wingtips (nice and aerodynamic) and you didn't put pontoons out there or something, that they would slice through the water pretty good. Just like the craft in the video does.


I would never consider flying a wig craft of any kind over ground, too many things to hit, and you can't exactly just hit the brakes.

[Bruno Ogorelec]

Ohmigod... you are right.

Strange, Bruno, but even I find that statement a bit unsettling. ;)

I seem to have run into a language barrier. What is it that makes it unsettling? English is not my first language -- sometimes I use it wantonly; what was it this time around?

[Al Belli]

Hi Bruno,

I, on occasion, have used the exclamatory " God "," Jesus " or " Jesus Christ ".
I have been told by some irate individuals that I should not use " the good Lord's name " in that manner. To eliminate the complaints from these types of individuals, I have subsequently found it easier to remove the words " God ", " Christ ", " Lord " and " Jesus " from my vocabulary.

These intolerant individuals have been, apparently , affected by the prevailing incidence of " politically correctness syndrome ".

Al Belli

[El-Kablooey]

Your english is perfect. I really just expected pages and pages of crap telling me why it wouldn't work (not you specifically).


I'm gonna build one. I have doen some more research and I think my hydroplane is gonna stay a hydroplane. When I am finished with it I'll start concentrating on wig design. I'd like to build one as small and light as possible. I want it to ride like a motorcycle, and I want to be able to control it in flight by weight shifting. That would give the pilot alot more "feel" of what was going on, and give the ability to adjust for the dynamically changing center of lift. The wings will be the floatation, with one hydrofoil underneath to get the wings up and reduce drag for takeoff. A high tailplane, out of ground effect in the rear. Then simply a motorcycle seat and some handlebars to hold on to mounted towards the front of the wing. I have been searching like crazy, and the smallest WIG I have found is the one at universal hovercraft. There very well may be a good reason for that, but I cannot find any information on failed attempts. I gues I'll have to try it just to satisfy my curiosity.

[Bruno Ogorelec]

Thank you, Al, for reminding me that my vocabulary can be offensive to some people. I am not religious in the usual sense of the word and I am certainly not politically correct, but I do try not to be intentionally offensive. My problem is that in Croatia, the people (who are about 92 percent Catholic) have never taken to avoiding the use of the Lord's name in vain. Indeed, all our curses and dirty language combine God, the 365 saints in the calendar, sex and certain other bodily functions in a very colorful way. (Or maybe in a very off-color way?) It spills over to my English to a little extent.

El-Kablooey, don't be surprised. I call my shots as I see them. With you I don't seem to agree very often but when I do agree, I have no problem at all admitting it right away. (In fact, even though we rarely agree, I have a sneaking suspicion you would be a good companion for a few beers and a session of shooting bull.)

Your pulsejet WIG idea hit the spot with me. I absolutely love it. It looks so excitingly Star Wars yet so eminently do-able...

I think you should build and test a prototype and -- if it works at all well -- approach the manufacturer with the idea of a race series. It could be a perfect vehicle for their promotion. With their experience and resources, they might also be the people to develop it into a formula racer.

[El-Kablooey]

El-Kablooey, don't be surprised. I call my shots as I see them. With you I don't seem to agree very often but when I do agree, I have no problem at all admitting it right away. (In fact, even though we rarely agree, I have a sneaking suspicion you would be a good companion for a few beers and a session of shooting bull.)

Well thank you Bruno. I have had the same thoughts about you. In fact, out of everyone here I would like to meet you the most. I like the way you see things (most of the time). People not agreeing with me is nothing new. I definately have a different way of looking at the world. In nearly all my posts, (and in real-life conversations with people) I come off as being "out there". You have to understand that my goal is never to be the one who is "right" or prove anything to anyone. I really just try to induce a little free thought in people's minds, help them break free from conventional thinking. Too bad it's not more effective.



I am going to build a small ultralight PJ powered WIG, something along the lines I mentioned above. I'm sure it will take some time, and I'm fairly confident that I can pull it off. Most of us could I'm sure if we put our minds to it. I'm going to have to spend alot of time reading, and some time experimenting with some 1/4 scale models. I will eventually get it right. Once I get an idea in my head it won't leave me alone until I suceed, at which point I immediatly lose interest and start hunting another project. I remember a quote, something about "it is not the destination, but the journey". Can't remember who said it though.

[El-Kablooey]

I've been thinking of a PJ WIG for a while, but I wanted to go all-out with the Star Wars influence. I was thinking of an engine platform that has two big engines and the fuel tanks, and have it tow the pilot on a second unpowered WIG.

You'd only be able to fly it on one of the dry lake beds, but that would add to the authenticity.

I saw something on the net about a towable wig, I think it was still conceptual though. The idea was to pull it behind a boat like a tube or kneeboard. I though it was a pretty cool idea. I think it was called the "manta ray", as its shape was very similar to one.