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Planing in 12s.

Started by Jimbo42, 29 Nov 2006, 06:42

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Jimbo41

Thanks for that offer of help Phillip esp. tech stuff.  :D

I too am a lowly amateur. But I'm motivated to try to do something to point the way to an optimised all-rounder hull. oh of course there's always the question of the beer and BBQ!

For anyone who's interested:

My tel No.'s in the book under Bretherick, James. or J.P. Or you can get me at home on +44 8145 951303. (GMT +1H).

I personally would prefer Easter as a date. The matter would then be to organise it all. I suspect the most difficult thing would be to arrange the boats and towing gantry. Anyone know of a suitable available stretch of calm water? I'll have my Man O' War to test out. Perhaps those awfully nice people at Spinnaker would be able to help out? Eh Simon ;D? (Who reads this C**PP anyway?)

So who's volunteering?  ??)

Jim N3130 and N3470 (Heave ho! and up she rises....Wot a drag!!!!)
 

angus

At the risk of being boring but its been a long very boring day at the office and this is not really my field  and I am officially hibernating hotchocolate not withstanding, but have you not got a slight problem if you are towing boats as you will be tending to creat a downward force while sails would I believe tend towards a lifting force also there are variations caused by heeling most boats go better flat but vary considerably in sensitivity to heel. I sure you boat designers know more about this than me.
Any way I sure it would be great fun towing boats baout the place, but me I'd rather be sailing and learning to sail a bit better (Well in my case hopfully a lot better).
All smoke and Mirrors. N2153, 2969, 3411

johnk

Ideal conditions for testing would be Beaufort force 0 - 1. Ideal conditions for sailing force 2 - ?

Lukepiewalker

If you were towing two at a time at either end of long pole, you could get a direct comparison and if nothing else could say one was draggier than another. If you did it this way then the conditions should be the same for the two hulls in question.

philipcosson

yes - I think the relative test has a lot going for it.

Angus - this is exactly the type of stuff we need - looks like we should attach the pull to the mast and have the centre of attachment high up on the towing boat then.

Of course the problem with all this controlled experimentation is you are laid open to probems of generalisation.

Philip
N3253
Philip<br />ex N3367, ex N3253

Barry

Surely generalised experimentation better than speculation and conjecture? ;-)

All power to the experimenters elbows!

As well as planing could the nose-diving capabilities be looked at?

Barry
N3364

Jimbo42


angus

#37
[quote by=johnk link=Blah.cgi?b=Cool,m=1164825767,s=32 date=1165512090]Ideal conditions for testing would be Beaufort force 0 - 1. Ideal conditions for sailing force 2 - ?
[/quote]

True but then i go best when theres no wind
And plenty of hot chocolate
All smoke and Mirrors. N2153, 2969, 3411

Jimbo41

NEWSFLASH!!!!!!!!!!!!!!

We may have water at Spinnaker to play on. I need dates and boats for Easter Hols time. Sundays are EXCLUDED. Simon aka Passion Pudding has agreed to take on his committee about this but needs a couple of date proposals. He also thinks he might be able to arrange an RIB (30 Hp).  I am reasonably flexible but want to get my yot back to Germany by 15th April at the latest and it'll take at least 3 days to do that comfortably.

So we are limited to  (a) day in 3rd-5th April or 9-11th April (avoiding Easter Friday Sat and Sunday). I need to find a tow rigg and a strain guage. Any leads anyone?

What's the opinion of everyone? I need commitment!!!!!

Do we do this or not? Any input from our NTOA committee?  ??)

Jim N3130 and N3470 (Pushing the boat out)
 

Jimbo41

BOING!

Come on now! Who's prepared to commit themselves to some interesting experimental (conjecture)?

Jim N3130 and N3470 (For the health of the N12 Class!!)
 

Jon_P

Jim,
I am keen and if do not end up going away with work I will be there, but I unfortunately cannot commit.  If I am there I would be happy to use photogrammetry to create profiles of the hull shapes.  Would give us a pretty accurate idea of the actual shapes of the hulls.
Jon

janeysailor12

.......................yaaaaaaaaaaaaaaaaaaaaaaawnnnnn  I've gone to sleep now!!!  Sorry to sound negative.....what's the point though????  How can you possibly measure accurately how fast a N 12 planes in anything but "normal" planing conditions blond I may be but I'm not dumb...towing a 12 aint gonna give you accurate results you need WIND....you need PEOPLE IN THE BOAT you need NORMAL sailing conditions....then there's the weight thing to consider, the wind direction, and speed where your helm and crew are sitting in the boat, as far as I can see all you are going to measure is how fast an empty N12 planes in a towing situation with no wind and no-one on board.....or am I missing something??

Janey zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz

Mikey C

Yup, I think you missed the entire thread...

Jim, I'm in - assuming dates dont clash with as yet un-announced Moth Fixtures. I like BBQ's

Cheers

Mike

Carbon Toys for fast girls and boys!

//www.aardvarkracing.co.uk

JimC (Guest)

I'll play if you want the Cherub. Mike C has my email I'm sure. I have dialogues with Julian Bethwaite from time to time, and can ask how they play it. I know that they tow with daggerboard and rudder in nowadays.

Equipment...

GPS
Towing poles rigged on boat
bags of building sand as ballast
two balances at least for on the water measurement
off water weighing facility (make sure all boats towed at the same weight)
suggest video camera would be a good idea - looking at the wave systems round boats can be *very* interesting...

janeysaior (Guest)

Ok....buying into this reluctantly.........so....how are you guys going to solve the problem of shifting weight around the boat when she gets up on the plane??  after all we sit well forward in sub planing conditions, and move aft and possbly pump to promote planing and if you try it with centerboard and rudder down I think you will have problems with boats shearing off one way or another.   Dont think sand bags will acheive this.

janey

P.S wot's on for the BBQ and how much beer will there be and will there be any Gin & Tonic available.

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