Weight equalisation

Originally posted by iGRF Originally posted by tink Originally posted by iGRF So what’s now being suggested the Contender doesn’t need a wire and trapeze at all because you’re an Engineer and I’m in marketing? You could fit wings on a contender and the crew could create the same righting moment as a trapezing crew, the key thing is where the crew c of g is. As a engineer this stuff is my bread and butter so my understanding of this stuff is rather relevant. Well I would beg to differ, then what do I know, I've only spent thirty odd years marketing harnesses and harness hooks in wind and more recently kitesurfing where the idiosyncrasies are very different. So you'll excuse me for choosing to find out for myself, when I can find a suitable harness with the option to vary hook height. As for fitting racks on a contender, or using your Toy example, they may very well apply sufficient righting force but they will be slower. If you are truly an expert engineer, then I shouldn't have to explain why, but if you wish, I'll try and find a better drawing programme to illustrate why.

I give up if you are not prepared to accept basic laws of physics I not going to try and change that

Originally posted by tink I give up if you are not prepared to accept basic laws of physics I not going to try and change that

Humans wrote the basic laws of physics and they have frequently been proved wrong.

That's the trouble with engineers, they only do as they're told and never question anything.

Rules are and have always been, made to be broken.

Edited by iGRF - 03 Jan 22 at 3:13pm

Originally posted by iGRF   Because the centre of gravity of the boat with a crew flat wiring is moved to an extent that the boat displaces less at the point of contact with the water so creates less drag and therefore goes faster,

Let's start in say 5 knots, with a 90 kilo crew sat in our Contender which weighs say 110 kgs all up, so 200 kgs point loaded.

Move the wind speed up to say 15 knots our crew has clipped in but is still pretty in board knees bent but part of his weight is going down directly through the mast via the trap wire, with maybe 10% less because he can lean out board.

Now move the wind speed up to say twenty five knots and our crew is flat wiring, his weight now directly supported via the wire, supported not entirely by the mast directed down through the hull, but in part supported by the wind side force. So where has the weight gone? It has spread over a wider area, like the twin cat hulls and in part supported by the mast and the calculation for this is something my maths can't extend to, but I'm sure is out there somewhere, don't make me look for it. But I can assure you is faster than if the weight were still supported directly by racks attached to the hull.



Edited by iGRF - 03 Jan 22 at 3:48pm

Interesting isn’t it?  Lots of people have told you that you are wrong about moving the trapeze attachment outboard increasing righting moment but no one has really explained why.