For some contrast you might look at the boats in the TP 52 class and the new Ker 43. Maybe take a look at some of the newest Reichel-Pugh boats.
These boats don't use chines. In fact the current popular stern shape is pretty much the opposite to what you would get with chines. These are round the buoys racers and designed for all round boat speed. ....
and that is why I say the chines are not there necessarily there to better sailing performance but to increase control. I don't believe a TP52 would be faster downwind with chines. If it was the case we would have seen some designers using them on those boats. Those boats are raced for a relatively short time with a big and expert crew and the increased control the chines would give at possibly the cost of a very small some loss of speed upwind doesn't pay off. They can control the boat even without the help of chines and the hull shape is what gives them the ability to go fast downwind on planing mode.
I agree that each case is a case and on different hulls chines are different and work at different heel angles. Regarding performance racers they are related with the best heel angle of the boat upwind, on cruisers they can be there for that, if they are performance cruisers or in the case of slower cruisers they can be there mostly to limit heel and to give a better boat control.
One of the reasons ker boats or TP 52 don't use chines is because they sail upwind with a lot of heel taking advantage of the power created by the big B/D ratio and big draft and for that they practically use all transom (that is designed for giving max hull form stability at that angle), I mean on the max heel position the transom is all sitting on the water so Chines make no sense and would only create drag.
Yes. I agree that chine is well defined. But it is not working.
It is 30 metric thingies above the DWL. It can't be working if it is not in the watewr. At that heel angle it only adds wetted surface.
On those beamy hulls with large transoms the waterline varies widely with heel on the transom. See, the chine is on the water and it is not needed much heel:
But I sure do like exchanging ideas with you. You are an amazing reference for whatever is new in European boats....I'm not Euro
Thanks. Regarding chines maybe you can give me some advise how these ones, on a very recent piece of American Yacht Naval architecture, work?
The Hunter 40 has much less beam and a much narrower transom than the Oceanis 41 and will sail upwind with more heel, as the photos and video can confirm but the chine is practically at waterline so any amount of heel would have it submersed. I don't get it
I saw the video and I still don't understand how it works, I mean positively in what regards performance or control. It seems to be adding drag only. I would really like you to give me a help on this, being that a non Euro boat, maybe I am missing something