Canoe Sprints

Why are you so sure the win was due to the towing tank work?

When fractions of a second are involved there are many other factors that
could contribute, e.g. physiological testing and optimisation, dietary
considerations, recovery maintenance (i.e. the period after races), judicious
choice of hull and paddle etc. etc.

I wish hydrodynamics and testing under controlled conditions was the reason
for the win, but there's no evidence it was a major factor.

 

Hey AH, did you get my e-mail?

 

No

 

Hi Leo,

Well of course it wasn't the only (or probably even major) reason, but every little helps and I would guess Team GB have taken a more scientific approach than some other nations. Of course, not every country has a tank long enough.

 

Every little helps, until it becomes counter-productive
I agree that GB would have taken a scientific approach, but my guess is that
the win was due to a kaleidoscope of talent and effort, and a little luck on the day.

In any case, the 200m thrash is an exciting addition to the kayak class.
Not as funny and hair-raising as the BMX, but definitely a crowd-pleaser.

 

I wonder if there would be any advantage to a boat made with flexible and slightly convex sides, so that when sitting empty on land it would be convex, and when loaded with people and sitting in the water it would be straight, but when raced would become concave from water pressure. It's kind of farting around with words, like Clinton and the word 'is', but it would seem to be within the rules.

 

If water pressure can flex the hull, so could the large forces exerted by the
paddler. It might be beneficial if you could co-ordinate the flexing through
some kind of feedback mechanism, in a similar way to how dolphins "ripple", but
I have a feeling it would be very difficult.

 

I'm thinking only in the sides, especially in the transition area from the bow partway back towards the beam, to give a finer entry. In the area where there aren't paddlers to exert local forces. Nothing that would ever go negative, but would be concave compared to straight.

Of course if a concave surface would have no effect, the question is moot. But if there was no advantage, why would they try to outlaw it?

In general, what is the layup for these boats, as in what resins and cloths? Is composite sandwich construction a part of it or is it all of it?

Lightness must be desirable, so the layup of the bottom must be different than the top. The layup in the paddler area where the power is generated in surges must be different than the ends, which get a more stable , continuous load transferred to them.

I'm sure state of the art construction is very secretive, but is there any information on what recent past construction entailed?

BTW, what is this ripple effect dolphins do?

 

My guess is it's a holdover from when the rules had minimum beam requirements. Some of the canoes and kayaks designed to those rules had very interesting shapes driven by meeting the minimum beam requirements.

 

How would that work? Averaging out beam measurements along the length so the average was minimum or more?

 

I think the minimum beam measurement required the beam of the canoe as some point within a zone to be some amount or greater. C1 canoes used to be diamond shape when viewed from the top. Nothing about averaging or the like. There may be someone else here who knows more than me.

 

Concave has frequently been declared a no-no in boating.

For this sport, concave on a flat bottom allows some early thrashing to entrain air to be captured under the hull. Significant wetted surface area reduction (and friction) is possible.

 

I suppose that means bubble generating paddles are out, too.

 

Define significant!

 

Theoretical potential is probably a whole lot more than realistic potential.

Still, anything more than a couple of percent reduction in drag would have people chasing away.