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Old Dec 23, 2011, 07:29 PM
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Probably would not need one, would test without first, prob Elevons on outer wings(r they too big to bE called OHS?).
Disadvantage, too much wingspan for low turns but dihedral would hElp.
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Old Dec 24, 2011, 12:32 PM
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Happy/Merry ... !

http://www.explosm.net/comics/2651/

Gabriel
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Old Dec 27, 2011, 06:27 AM
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enkranoplan-sidewall hovercraft convertible

I always wanted to build a simple RC hovercraft, so I converted my "Wind" ekranoplan to an enkranoplan-sidewall hovercraft convertible.
It can be easily converted back and forth in a few minutes. As a sidewall hovercraft it moves like an ordinary hovercraft






Gabriel
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Old Dec 27, 2011, 11:57 PM
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Clever. Here's a thought: maybe build one that starts going as a hovercraft to get going, then the flap on top shuts and the skirt lifts up to function as a wig?
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Old Dec 28, 2011, 04:50 AM
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Thanks!

I took a thought for this kind of solution, but there were many problem that couldn't be solved on this model. Biggest problem is that the CG in the modes are different. On the other hand to make a retractable/folding skirt is also real challenge.
As an ekranoplan model, it takes off quickly (it needs about 2-3 meters) so actually it doesn't really need this kind of assisted take off.

Gabriel
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Old Dec 29, 2011, 10:20 AM
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Wind was converted back to ekranoplan mode, and its 'final test' was done today. It was a high speed test and a max. flight height test. Until now I didn't dare to fly it on max. throttle setting.
With a fresh charge, its max speed could exceed 50 km/h but it's not safe. At this speed its able to fly 10-15 cm high, but it rolls back and forth if I use the rudder. The whole high speed test was just frightening .
I stick to the max 4-5 cm flying high.

I also tried it on grass. Its able to move and turn on grass if it has enough power. Of course its able to fly over grass if it's not too tall. Its able to take off from grass, but its not recommended because a little bump could easily damage it.

I added a LED bike light to it for night flying. It was also tested.

Gabriel
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Old Dec 30, 2011, 12:08 PM
flying since 2000
Winterthur ZH, Switzerland
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hey gabriel

cool! you got any video or pic of the night flying?

I'm currently a bit in a phase where I don't like to experiment. Currently I'm building a kind of a flying shoe-box bixel, in other words a possible practical application of a Bixel Wig, as a freighter. It will be powered by a 300W Impeller with 3s LiPo. the elevator will be splitted, so it can be used as a elevator and aileron. my old bixel turned upsite down while flying oge, probably caused by the high FG (thats also the reason why I use an Impeller this time, to keep the CG as low as possible to avoid the turning upsite down in oge flight).
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Old Dec 31, 2011, 01:39 PM
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Quote:
Originally Posted by RdsG View Post
Thanks!

I took a thought for this kind of solution, but there were many problem that couldn't be solved on this model. Biggest problem is that the CG in the modes are different. On the other hand to make a retractable/folding skirt is also real challenge.
As an ekranoplan model, it takes off quickly (it needs about 2-3 meters) so actually it doesn't really need this kind of assisted take off.

Gabriel
It might be something to consider on other WIGS. I was thinking the skirt could be hinged to shift together with the power vent, perhaps progressively with a servo. Maybe along with a sliding weight for CG? Just some random neurons firing, as usual.
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Old Jan 01, 2012, 09:26 AM
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@sfluck
I don't have photos or videos about the night flying. There's not much to look at, just a pair of white LED in the dark come and go

@dll932
Hoverwing 2VT and WSH-500 use similar take off assist.
youtube.com/watch?v=JAsNzQJ0IH8

WSH-500 first take off!:

http://www.youtube.com/watch?v=iJHin...2GEIhXwkwztA4O

Gabriel
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Old Jan 01, 2012, 04:39 PM
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fantastic, that must feel good skimming so
close o the sea!
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Old Jan 02, 2012, 06:20 AM
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thats awesome! it really left that chase boat behind fast!
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Old Jan 02, 2012, 01:48 PM
flying since 2000
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When I first saw the video I was doing jumpingjacks . I guess I have to go to Jaeju / Gunsan some time in the future... I think I read a korean article the other day (with google translator ), and it said the WSH-500 will go into service in March 2012! Unfortunately I don't know which article it was, found it on the Wingship Tech. Facebook page. it's nice anyway that Wingship Tech. shares so many things over Facebook. I keep my fingers crossed...
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Old Jan 03, 2012, 06:24 PM
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I have to admit that I didn't understand really the principle of wing chord dominated ground effect (as it turned out lately). I thought that ram air is always needed to produce ground effect, but it's not true!

An airfoil that produce lift always take effect by chord dominated ground effect if the wing is close enough to the surface. So its AoA is not relevant (until the wing is producing lift).

Ram air is also a kind of ground effect phenomenon, which produce additional lift close to the ground. Normally these two kind of effect works at the same time.

But an asymmetric airfoil (for example a Clark-Y) can be effected by ground effect without any ram air.



Now this craft is makes sense to me. It's a momentum curtain hovercraft-ekranoplan hybrid. Its airfoil shaped fuselage able to produce ground effect at near zero AoA. :




Gabriel
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Old Jan 06, 2012, 12:37 PM
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I have a little theory about single wing elkranoplans that I would like to throw at you. I'll do some proper tests aswell, but suspect that you can give me an indication of if it is worth testing.
My theory is as follows:
For multiple gev's of the similar design the angle of attack of the wing affects two things. It affects the amount of air pushed under it, and thus the glide height. And it also affects the maximum range of the center of gravity.
So a gev with a 0 or 1 AoA will skim very close to the ground for it's size and speed, but will tolerate the CoG being just about anywhere.
And a gev with a higher angle of attract, but of the same, will fly higher, but is more fussy about the center of grravity.

This may extend through the different basic designs too, but I am much less sure. A bixler with it's flat plate as a wing, at very low AoA (0 isnt it?) Can have its cg within maybe a third of its lenght. Whereas the reversed delta desighn has a much higher fly height (yup) but is more sensitive to cg position (yup).

Do you think that this is possible and worth testing? Have you noticed this in your models.
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Old Jan 06, 2012, 01:00 PM
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Quote:
I have a little theory about single wing elkranoplans that I would like to throw at you. I'll do some proper tests aswell, but suspect that you can give me an indication of if it is worth testing.
My theory is as follows:
For multiple gev's of the similar design the angle of attack of the wing affects two things. It affects the amount of air pushed under it, and thus the glide height. And it also affects the maximum range of the center of gravity.
So a gev with a 0 or 1 AoA will skim very close to the ground for it's size and speed, but will tolerate the CoG being just about anywhere.
And a gev with a higher angle of attract, but of the same, will fly higher, but is more fussy about the center of grravity.

This may extend through the different basic designs too, but I am much less sure. A bixler with it's flat plate as a wing, at very low AoA (0 isnt it?) Can have its cg within maybe a third of its lenght. Whereas the reversed delta desighn has a much higher fly height (yup) but is more sensitive to cg position (yup).

Do you think that this is possible and worth testing? Have you noticed this in your models.
What do you mean single wing ekranoplan?
What kind of wing profile do you want to use?

If you mean flat plate wing, low 0-1 AoA won't work, since flat plate wings generate almost zero lift at low AoA.

Sensitiveness to CG is depends on many things. It depends mostly on the size of the stabilizer and its relative position to CG and to the other wing.

Flying height is also depends on many thing. Generally WIGs without out of GE stabilizer fly at lower hight, but it depends on chord length and speed etc...

Gabriel
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