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Sean Atterbury - n/a
2-Aug-06, 12:13 PM
I have notised these funny configured craft this year.



It would apear that several of the skirts have been left out of the design and the craft still works well if not better than last years craft.



How is this possible, I know that when I lost several of my rear segments the craft still worked but not that great, kinda draged the back around a bit except when going flatout.



Would the craft not loose all its lift like that, I do not know.



Please explain...............

http://hovercraft.org.uk/images/icons/smiley_icons/icon_confused.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_confused.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_confused.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_confused.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_confused.gif

charfont - n/a
2-Aug-06, 03:50 PM
possibly you may get the full answer but after the worlds.... basically keeps it fast and flat on the deck... http://hovercraft.org.uk/images/icons/smiley_icons/icon_wink.gif

tonybroad - n/a
2-Aug-06, 04:58 PM
the top F1's are generating enough lift air to sacrifice some through the hole at the back and still have a rock solid skirt



i understand the idea is to have air passing above and below the craft when it tries to become airbourne rather than the craft suddenly becoming like an open barn door in the wind - the hole is an escape route



and it works, they are definatley more stable at speed which was the designers intention i believe - nice one Conrad

jon_curtis - n/a
2-Aug-06, 07:39 PM
thinkin about the fluid dynamics of this, it may

have the effect of keeping the craft on the deck!

Sean Atterbury - n/a
3-Aug-06, 06:51 AM
All true, but then why not just............



You know that is, now that I think about it, realy clever, you see the way that there are like paddles sticking out the back that will also protect the rudder when vertical and still letting air through the hole in the middle. http://hovercraft.org.uk/images/icons/smiley_icons/icon_biggrin.gif



But again, this all goes against the principals of hovercraft, this being the faster you go the more lift you need. http://hovercraft.org.uk/images/icons/smiley_icons/icon_confused.gif



So it would also be possible then to chuck in a small lift engine as the craft uses mainly the ground efect theory most of the time and will then only need the lift engin at lower speeds and thus not need as big a one. Thus inproving power to weight. http://hovercraft.org.uk/images/icons/smiley_icons/icon_biggrin.gif



Its great to see pioneers out there taking the sport into the future with gusto.



Wonder what will be next. http://hovercraft.org.uk/images/icons/smiley_icons/icon_rolleyes.gif

jon_curtis - n/a
3-Aug-06, 05:19 PM
now your talking rollocks!

Sean Atterbury - n/a
4-Aug-06, 06:04 AM
Rollocks http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif



Y?

jon_curtis - n/a
4-Aug-06, 12:49 PM
quote



So it would also be possible then to chuck in a small lift engine as the craft uses mainly the ground efect theory most of the time and will then only need the lift engin at lower speeds and thus not need as big a one. Thus inproving power to weight.



thats rollocks



im guessing its more to do with good old mr Bernoulli. and his very interesting principles of fluid dynamics!"



if you look at the pic of the pintail bottom, there looks like a bag loop around the outer periphery of the hull bottom, before the planning surface goes up.

there are also high pressure segements on the craft, you can see the flaps.

the lift is provided by the high pressure loop of air trapped between this bag loop and the segment. around the front and sides of the craft.

there therefore is an area under the craft where the lift air would travel into.

this is then a compartmented cushion.



if there is a hole at the back, which is a small hole (as it is compared to the width of the craft) the air exits this hole and takes the air with it, thats in the inner middle 'compartment'. suppose its a bit of venturi and bernoulli, maybe the air is decreased in pressure a litte due to a velocity increase in the middle compartment, as it moves forward and air travels out the back at speed.

this would have the effect of sucking the craft down to the deck as it moved forward at speed. would make for a very fast and stable craft.



so yeh nice one conrad!



if im right do i get a free skirt seggy? LOL

pest619 - n/a
4-Aug-06, 08:44 PM
actually nice one Dan



-Twas Dans idea origionally but wether the same design appearing on two craft at the same time was a coincidence it remains to be seen...



it only works effectivly at high speeds and apparently the craft are harder to handle in corners (obviously way better than mine anyday- its all relative) there are also lots of sausauges underneath that you might find interestin too...

jon_curtis - n/a
5-Aug-06, 02:51 PM
dans a clever man then! http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif

Sean Atterbury - n/a
7-Aug-06, 08:51 AM
Clever man, well done....



Wonder what's next, like formula 1,(GP) this is just the sport to continuously improve the technology. http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif



Did any of you catch the GP this weekend?



Schumie was a real ideot by crashing his car, now he will have to work twise as hard to get the championship, not that he is my man but anything is better than that Alonso guy.



Good on Jenson, it's been a long time cumming. http://hovercraft.org.uk/images/icons/smiley_icons/icon_biggrin.gif

kach22i - n/a
11-Aug-06, 04:00 PM
Atters, could you please tell us when and where these photos were taken and at what event?



Also if you could post larger or more detailed images it may help us all understand the design intent more clearly.



Outstanding discovery.



Cheers, George/kach22i.

Happy Snapper - n/a
14-Aug-06, 07:36 AM
I think the first picture is one of mine



taken at whittlesey july this year.



Rebecca.

Sean Atterbury - n/a
14-Aug-06, 12:58 PM
Yes the one is yours Reecca, thanks



the other is from the french site, not sure from where though as it was in french..... http://hovercraft.org.uk/images/icons/smiley_icons/icon_confused.gif



Can't be any clearer sorry.

kach22i - n/a
14-Aug-06, 01:58 PM
I think the first picture is one of mine



taken at whittlesey july this year.



Rebecca.




Rebecca, is there any chance you could chrop and lighten the photo and repost it here?



If you have a large orignial could you e-mail it to me so I can doctor it for everyone?



EDIT:

I went to Rebecca's homepage: http://hovercraftvideo.co.uk/ (hovercraftvideo.co.uk/)



Looking at what Rebecca and Paulz posted for Whittlesey 2006 I've found other interesting skirts, although nothing as radical as the Twin tail design.

kach22i - n/a
14-Aug-06, 02:26 PM
The twin tail pictures or Rebecca's are in the very high 400 series, like #496.



Here are some of Paulz's pictures.



http://80.6.118.13/2006/Whittlesey/Paulz/WH_P_06_118.JPG



http://80.6.118.13/2006/Whittlesey/Paulz/WH_P_06_103.JPG

hover t - n/a
14-Aug-06, 04:47 PM
Is this any good

index.php?t=getfile&id=339&private=0



Trev

kach22i - n/a
14-Aug-06, 05:32 PM
hover t, if it were lighter it will show more detail - nice size though.



I guess my true inquire is in this sketch I did the other day (should be dated August 9th not September 9th, I was in a hurry and got ahead of myself).

Paul Fitz - n/a
14-Aug-06, 06:35 PM
Download Irfanview (Free image viewer and manipulator)



http://www.download-zone-free.com/irfanview/



(very small, very good quality and powerful tool)



use Image|enhance colours to alter the brightness of the image.

the image can be saved as an independant file directly from your browser (with Rebeccas' permission of course http://hovercraft.org.uk/images/icons/smiley_icons/icon_surprised.gif), or go to the worlds and look at the real thing http://hovercraft.org.uk/images/icons/smiley_icons/icon_surprised.gif)

kach22i - n/a
14-Aug-06, 06:54 PM
Download Irfanview (Free image viewer and manipulator)



http://www.download-zone-free.com/irfanview/ (www.download-zone-free.com/irfanview/)



(very small, very good quality and powerful tool)



use Image|enhance colours to alter the brightness of the image.

the image can be saved as an independant file directly from your browser (with Rebeccas' permission of course http://hovercraft.org.uk/images/icons/smiley_icons/icon_surprised.gif), or go to the worlds and look at the real thing http://hovercraft.org.uk/images/icons/smiley_icons/icon_surprised.gif)




I can lighten images and get increased detail with ACDSee for Pentax, it just helps to start with the highest quality source you can.



I'm staying home this year, don't anyone get hurt peaking up skirts now. http://hovercraft.org.uk/images/icons/smiley_icons/icon_biggrin.gif



From all the images posted, I'm getting the feeling that a lot of the current innovations are happening where we can't always see them. This however does not mean people are not out there making a better mousetrap for us.

kach22i - n/a
15-Aug-06, 07:08 PM
Thanks to Rebecca, I now have a better image to start with. It appears that the inside part of the skirt is attached to the upper position (refer to sketch).



http://forums.pelicanparts.com/uploads8/Whittlesey_20061155668535.jpg

jon_curtis - n/a
15-Aug-06, 08:09 PM
i think it looks like mate, there is a strip of ally, holding the bag loop to the hull. i doubt this craft has a massive hoverheight, the lift air is trapped between the bottom of the segment and that bag loop sausage thingy.

Sean Atterbury - n/a
16-Aug-06, 06:42 AM
Quote: (i doubt this craft has a massive hoverheight)



I think that is the point as the F1 craft seem to be more on there sides and rear than most hovercraft.



Maybe a new name is in order, how does the Lowfliers, or Madhatters Sound. http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif



They are for sure not in the same class as the rest of us.



Maybe even, The Cut Above....



or last try.



"You have absolutely no will to live in one of these"



OK maybe a bit long but true.



ooooo oooo one more, "The suiside club"



http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif

jon_curtis - n/a
16-Aug-06, 08:18 PM
your anoying you be a good one for you!

nickyd - n/a
16-Aug-06, 11:10 PM
I don't think the craft with the orange skirt pictured above has any special skirt design. Looks like a standard eagle skirt to me....

Sean Atterbury - n/a
17-Aug-06, 06:48 AM
That's Tony's craft, he however had a bit of an incident that weekend and still endid up in the points.



Good on you Tony.

pest619 - n/a
17-Aug-06, 09:56 AM
Yeah, looks like theres been a lot of repairs underneath as well, sum1 mustve beaten up that hull... i wonder who the driver was... http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif

Sean Atterbury - n/a
17-Aug-06, 11:25 AM
http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif

kach22i - n/a
17-Aug-06, 04:55 PM
I don't think the craft with the orange skirt pictured above has any special skirt design. Looks like a standard eagle skirt to me....




Maybe not a special skirt, however I'm interested in knowing if those holes under the engine area are plenum feed holes.



Any observations on this?



I know it's blurry picture, but some of you really know these craft well and I do not.

nickyd - n/a
17-Aug-06, 08:20 PM
The reason I know that's a standard skirt is because it's mine!



And yes the hull has taken a serious battering. The wood panel at the front is to replace the bit of fibreglass that is now in the bottom of the lake in Claydon!



As for the holes at the back, I'm not sure if I should give away my secrets............Ok then I will. They aren't holes at all. They were, and I drilled them so that I could do the nuts up on the engine mounts. The mounts sit on top of the air tunnel so I cut these holes to give access. I then glassed the holes back up again.



So no secret lift holes I'm afraid!



Nick

Paul Fitz - n/a
17-Aug-06, 11:15 PM
Not holes, they are the 4 x fixing positions for the engine frame with 2x fixing positions for the fan frame just behind. The craft uses a flexible coupling between the engine and lower pulley.

kach22i - n/a
18-Aug-06, 02:45 AM
The mounts sit on top of the air tunnel




Interesting story, knew it was different, but was so blurry I could not piece it together.



Is the tunnel and mount anything like this one?



http://home.tiscali.nl/hoverblade/media/albums/bouw/images/DSC02910.jpg

http://home.tiscali.nl/hoverblade/media/albums/bouw/images/P1010061.jpg

nickyd - n/a
18-Aug-06, 01:45 PM
Hi,



The air tunnel i mentioned is similar to yours I think. It serves two purposes in my craft. Firstly it stiffens the floor up. I think the idea is that it also allows some of the air coming from the fan to be tunneled through to the front. Presumably to help reduce plough in. Although in practice I'm not sure how much air actually passes through it, and in what direction.



Paul was half right with his answer. My craft did used to have flexi coupling and separate fan frame, but thats all gone and it now has a 503 in it sitting on four aniti vib mounts. There are six holes in the bottom because I have used about five different frames in there over time, and they weren't all neccesarily in the same place!



Nick

Paul Fitz - n/a
31-Aug-06, 09:44 PM
"six holes in the bottom because I have used about five different frames in there over time"



Ah! a pincushion craft http://hovercraft.org.uk/images/icons/smiley_icons/icon_surprised.gif)