Rudder shape ?

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trebor
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Re: Rudder shape ?

Post by trebor » Mon Dec 14, 2015 8:47 pm

Matt,
Birds, Bats and insects etc, (I was hoping to put teradactill, but I could not spell it), have had wings since the year dot, but I am sure someone had the Patent for the "Spitfires" elliptical wings (struggled with elliptical has well, hope its correct). :D
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Max McCarthy
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Re: Rudder shape ?

Post by Max McCarthy » Mon Dec 14, 2015 9:41 pm

trebor wrote:I am going to try Tubercules, combined with a Chord.

I hope I will not be breaching someones patent ?
Is this being built by you or professionally?

If I'm honest, from what I've read about turbocles, they seem to make no difference to not much of a noticeable advantage when used in aerospace applications, but it is certainly an interesting experiment (although adding to the complexity of the build somewhat).

Let me know how you get on, it'll be interesting to see the results....

Cheers,

Max
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roger
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Re: Rudder shape ?

Post by roger » Mon Dec 14, 2015 10:23 pm

Toby Barsley-Dale, has a tubercules rudder on his Hornet. He rates it and he seems to go pretty quick as well. I am sure he would be happy to give his opinion.

He will probably try to sell you one as well as he has a vested interest. :D
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Max McCarthy
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Re: Rudder shape ?

Post by Max McCarthy » Mon Dec 14, 2015 10:36 pm

roger wrote:Toby Barsley-Dale, has a tubercules rudder on his Hornet. He rates it and he seems to go pretty quick as well. I am sure he would be happy to give his opinion.

He will probably try to sell you one as well as he has a vested interest. :D
Yes, as I have heard.... :wink:

I think Steve Goacher had one built for his AC, but I think he said there was no noticeable difference....

Either way, at least it's another route of development, something quite apart from conventional rudder shapes, to say the least.... Almost reminds me of Alan Powell's experimental sails in his IC:

http://www.intcanoe.org/forum2/viewtopi ... c529#p6185
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trebor
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Re: Rudder shape ?

Post by trebor » Mon Dec 14, 2015 10:47 pm

Robert
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Re: Rudder shape ?

Post by Nigel » Tue Dec 15, 2015 11:48 am

I seem to recall that Mr. Mitchell based his Spitfire wing design on that of a seagull.

interesting to work through the reasoning behind a design - what is different and how does that change how it will perform - but sometimes people get inspiration to try something because I just feels right.

have you thought about inverting the curved edges of the tubercules so they become winglets blended in to the main blade so there are no sharp angles?

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Re: Rudder shape ?

Post by JimC » Tue Dec 15, 2015 1:07 pm

My understanding was that the Spitfire wing planform was principally governed by the desire to fit 4 guns in a thin wing.

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Re: Rudder shape ?

Post by trebor » Tue Dec 15, 2015 6:30 pm

Max, I will be building it myself.
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Re: Rudder shape ?

Post by Nigel » Tue Dec 15, 2015 6:34 pm

Hi Jim,

perhaps I am recalling a bit of poetic licence in "First of the Few" - I do remember a scene with Leslie Howard staring wistfully up at the soaring gulls.

Here is one bit of Mitchell advice where it may be appropriate to substitute "dinghy" for "aeroplane":

If anybody ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me: it's all balls.

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Re: Rudder shape ?

Post by trebor » Tue Dec 15, 2015 6:53 pm

Nigel,
Did they use Balls as a swear word when Mitchell was alive ?
Jim,
I think originally the wings were designed for a pair of Cannon, at the eleventh hour it was changed to four Brownings per wing.
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Re: Rudder shape ?

Post by realnutter » Tue Dec 15, 2015 7:37 pm

Nigel wrote:Hi Jim,

perhaps I am recalling a bit of poetic licence in "First of the Few" - I do remember a scene with Leslie Howard staring wistfully up at the soaring gulls.

Here is one bit of Mitchell advice where it may be appropriate to substitute "dinghy" for "aeroplane":

If anybody ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me: it's all balls.
Some great clips from that movie in this modern music video:

https://www.youtube.com/watch?v=_u4Md_aXVJE

Public Service Broadcasting are an interesting band.. they edit archive film, and then put music to it... lots of stuff about steam trains as well as vintage planes..
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trebor
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Re: Rudder shape ?

Post by trebor » Tue Dec 15, 2015 8:26 pm

Nice one Matt.

Regarding Seagulls and wing shape,
Quote, Mitchell to Beverly Shenstone,
" I don't give a b----R wether it's elliptical or not, so long as it covers the guns"
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Max McCarthy
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Re: Rudder shape ?

Post by Max McCarthy » Tue Dec 15, 2015 9:39 pm

trebor wrote:Max, I will be building it myself.
Well I'm certainly interested in the results. I look forward to seeing how it ends up....!

Cheers,

Max
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Re: Rudder shape ?

Post by trebor » Tue Dec 15, 2015 10:15 pm

Max,
Me too. :D
I cannot test Rudder scientifically, but I can tell if it is worse than original.
If your boat gives off a good Rooster tail, and it disappears after fitting new Rudder blade, obviously you have removed some drag.
I hope to reduce surface area by about 30%.
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Re: Rudder shape ?

Post by alan williams » Thu Dec 17, 2015 10:58 am

If it gives off a Rooster tale you have increased the drag.

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