Friday, September 13, 2013

North Sails- Keepin it simple !


Tour-de-force again from Norths, with the quintissential 1990s CHS / IRC and one design
supremo, the J35.

This video really is about the basics for being a competent racing sailor and crew, it is not very advanced and I like that as you will know: Listen to the guys: they have a kind of jamais vu, naievitet about their conversations on board, yet they are all pro sailors with world champions amongst them. They have never sailed a j35 before and most of them have not sailed together, yet there is a freindly discursive , democratic atmosphere on board immediately.

THe fact it looks like VHS with its blocky highlights means in fact that it is

easier to see the draught and depth changes!

Things I learned or refreshed my rusty old heid with:

1) WHen you put the main down the traveller in stronger wind, you are not just

dumping and blading out. You are in effect moving the whole angle of attack,

much like twist at the top, now you are making a greater angle for the sail to

fly, and in fact you can be increasing the drive forward as the main centre of

effort points more forward, as in the theory of twist, only now the whole sail

can fly at a steeper angle. This depends also though, on the slot, and if you

close the slot on a big genoa boat like a j35 you are killing both sails. On a

more modern IRC with a jib, then you can power up this way for lower pointing

and wave punching with the slot fairly closed.

2) go with feel and target speeds more than just looking "right" in terms of sail shape and sheeting positions/tensions / traveller set up.


3) remember that the back stay may take out the luff sag, but that is not all!

It also usually moves the draught back, which is bad for sawing ie having a

range to sail to through the waves and differing wind strengths. You need to

take up on the halyard to move the draft forward again, and also this can

close up the slot again at the top of the sail. You then use the sheet and

traveller (jib car) to fine adjust the twist and power

4) spinnaker - do a test curl to see if the law of opposites should be obeyed: ie low curl, take pole up and converse: this is graphic here because the big j35 kite becomes MORE stable by being higher, the pole projects forward more and the entry is flatter, while the exit is probably more controllable as the sail will open quicker from the flatter shape.

5) Spinnaker - a little counter intuitive again- bringing the pole back as far as practical on a reach will move the centre of effort forward and reduce healing. Remember apparent wind effects, a puff will actually make the wind go aft!

6) Moving the pole back when running in gusts: this flattens the sail meaning the pressure bubble is escaped more quickly by the gust , thus depowering!

7) keep the pole back in a broach, ease the sheet and wait until the bow is down again and the boat level and then trim on. If you are pinned, get the halyard off, but keep the sheet on the winch. You need to be able to round up level and bear away

8) Kicker decided twist off wind in the top third of the sail. main sheet then acts more like the traveller, altering angle of attach \.

9) keep on working on the run, and the next beat , you can draw in the places with getting the gear shifts right and being proactive on wind communications - boat speed makes you a tactical cliche!

10 ) call the Lulls as well as the gusts! In the northern hemisphere a lull at the end of a gust, or just a lull will tend to be a header on starboard as the wind goes left, converse on port. That is given the wind is from the same general direction and there is not a wind shift, there is a 3D velocity effect at play. Going light ahead while on starboard can mean it pays to go a little early onto port such that when the new light block fills the race course you punch into it at speed, get a lift on port after the speed falls and avoid tacking in the light patch.


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