You are 100 percent wrong with this observation.

Take a look at an albatross sailing on the air currents
above the ocean. If you perchance to see one end-on
you will note their wing tips flare upwards and outwards.

Picture one of the bird's wings placed vertically and you
will see how incorrect your trying to close the leech
of your sail is. This a common fallacy with those who
fancy themselves racers. They are too busy looking
at all the other racers doing it wrong and can't see
folly and inefficiency even when they look right at
it.

Another little mother nature test is try feeding some
seagulls sometimes. The few being fed will put out
the word and others from all around will come
barreling in. They approach at high speed. Then
they draw their wings in a nice curve effectively
shortening their wing span and they feather and
stall. This inefficiency acts like a brake. What
you do with a sail with a closed leech in lower
winds is stall the damned thing out.

S.Simon


"The_navigator©" wrote in message ...
It's far from simple. In the upper sections, leech control is critical
to determine how much draft is right. As wind velocities at the top are
higher and if angles of attack are set to be optimal by twist control
then the upper secion should be slightly flatter. This is possible
enitirely due to the stiffness of modern fabrics that will properly
support their leech as the wind pressure increases. Have a look at the
North web site for some photos of their racing sails and try to find
full upper sections.

Cheers MC

DSK wrote:

It is the simple fact that a well cut sail will be
relatively deeper in the upper sections.