Monday, June 30, 2014

Chop



Most dinghy sailors don't like chop. You are cruising along all fat dumb and happy on a light wind day on relatively flat water and all of a sudden you hit some nasty short waves stirred up by some thoughtless dude in a powerboat who has been blasting around on your race course. Your bow slams into the chop, the boat almost stops, and by the time you have got the boat moving again your competitor on the other side of the course has gained several boat lengths on you.

Chop! Ugh!

That describes the conditions where we were racing on Saturday at Duxbury. The wind hardly ever got above 5 knots and, because it is now summer, all the yahoos from Duxbury were out on the water zooming around in their motorboats. So there was quite a lot of motorboat chop. But only in certain places. Over most of the course the water was flat.

Usually on a day like that I would start whining and complaining and probably give up racing early. But, for some unknown reason, I was in a more positive and constructive frame of mind on Saturday.

Hmmm, I thought to myself. There's chop. That's interesting. What can I do about it? If I can find a way to sail through it without getting slowed down too much (and my competitors don't) than I can make some gains.

So I experimented.

When I saw myself heading towards some chop I moved back in the boat a little if I was sitting right up by the centerboard (as one does in light airs.) And I heeled the boat to leeward as the chop approached. Both of these seemed to lessen the impact of the chop. And flattening the boat again after getting through the chop gave me an extra bit of acceleration too.

The other thing I did was if I was approaching some chop on the beat where I would be hitting the waves head-on and there was no good strategic or tactical reason not to tack, I would tack. I either avoided the chop altogether or took it on the side of the boat which was no real problem.

It seemed to work. I won three races, and had two seconds and a third. Not a bad day at the office.

Of course it probably wasn't all to do with the chop. When we were talking after the races one of my friends complimented me on my finishes and said he couldn't understand why I was faster in light air when I was so much heavier than him. (I think he means I'm fat.) I gave him a spiel about my momentum theory - that heavy people do well in light airs in Lasers because their extra weight gives the boat more momentum to keep going through the lulls (and maybe the chop.) He seemed to buy it.

But when I told the guy who had won the other three races about my momentum theory, he dismissed it out of hand. (He was lighter than me and faster if anything.) It's all about having the skills to keep the boat moving, he explained. Nothing to do with momentum.

Whatever the reason. Chop, momentum or skill, my finishes were 2,1,3,1,2,1. I'll take it.

Or maybe I was just lucky?

Does anybody have any other suggestions about what to do with chop?


15 comments:

Baydog said...

Pan-roasting is a favorite of mine, with salt, pepper, and freshly chopped rosemary.

Tillerman said...

Excellent idea Baydog. How does Rosemary feel about it?

Baydog said...

It's a sticky subject

Tillerman said...

Rosemary was never the same after having that baby, the one they made the movie about.

meech said...

I like the idea about increasing amount of tacking

Tillerman said...

I'm pleased you agree with me meech. But not everyone does.

I was at a Laser clinic almost 20 years ago which was being run by a coach who was one of the top US college coaches at that time. And I remember asking him whether he would ever tack to avoid chop. He gave me a categorical, "No."

I didn't ask him any follow-up questions at the time but I guess his reasoning would be that you would lose as much distance or more by doing a tack, as you would by dealing with the chop effectively (by heeling etc.) And I also guess that he would have questioned why I would want to tack if I was already on the correct tack in the first place.

There may be some merit in the first objection. But I don't think I lose much by doing a really good roll tack in light air. And I only tacked when I was already thinking that I would have to tack soon anyway for some reason.

And I guess it depends on how light the wind is, how heavy the boat is, how well it accelerates after being slowed down by chop etc. etc.

As another very good coach said, It Depends.

Doc Häagen-Dazs said...

As a Laser sailor, I was well overweight for the class. (If Rooster rigs had been around at the time, I think I would have been tempted to bag one for certain regattas.) I do recall dealing with chop in just the manner you have described.

Now with my heavy displacement 38-foot 'Laser', I am a firm believer in momentum advantage in light airs, choppy waters. I sometimes use a momentum start: revving the motor and then switching it off 5 seconds before the warning signal and coasting across the start line. Going to windward mark, traveller to weather, sheets eased to get a big twist to my large, fully-battened, big roach mainsail. Crew ballast to leeward to get that heel and the bigger LOA, Baby. The whole idea is to keep her moving with as few tacks as possible. When the wind stops to nil, those light guys stop in their tracks. Works! To avoid being DFL, anyways!

Keep Reaching said...

Very interesting - I will have to try these techniques.

In tacking for chop, I assume you are tacking in response to a particular wave or set of them instead of general chop. If that is so, why not just bear off a bit, picking up a little speed and then come up after the waves subside.

Also, why does heeling to leeward help?

Tillerman said...

Yes KR, I am talking about tacking in response to a very localized piece of motorboat chop in otherwise flat water and when I am heading roughly directly into those waves. Bearing off to get more speed through the waves sounds like another good idea. I will try that next time I am sailing in similar conditions. I would certainly do that when beating in windblown waves when meeting a particularly steep set of wave fronts.

I am not entirely sure why heeling to leeward helped but it seems to. I just did a bit of a google about the question and found one site that says you should "heel the boat over more as you approach a wave set to minimize the amount of wetted surface that has to deal with the wave." No idea if that reason is correct but it seems to work.

Doc Häagen-Dazs said...

Come on, Skipper! You're not giving away any closely kept secrets away here: it's well known in light airs and heavy chops, part of the battle is to keep your sails from flopping and losing shape. Really. Back in the day, in these conditions, we used to capsize before the start just to get our sails wet so they would at least hang as if hey had wind in them.

Tillerman said...

Of course I'm not giving away any secrets. If I knew any secrets I would be a better sailor than I am. All I am doing is telling folk what worked for me on one day and asking for other suggestions.

Thanks to Doc for suggesting wet T-shirts and to Baydog for suggesting chopping Rosemary.

Jeremiah Blatz said...

I don't know anything about Lasers, but on a J/24, taking the chop at about 45° is ridiculously faster than any other angle. In light air, it's faster to luff head to wind to approach at the correct angle than it is to stay close hauled. (It's even faster to fall off to a reach, of course, but I was messing around the other day.) I imagine head to wind in a Laser is slow...

George A said...

Tillerman: It's been ages since I paid attention to what's permitted on a laser, but does the class permit one to rig an inhaul for the tack of the sail? On my Europe dinghy/Classic Moths, when encountering a day with light air and chop I slack off the outhaul, sweat up on the inhaul (to bring the draft closer to the mast) and then reset the outhaul as required. This basically "downshifts" the rig to a lower, more powerful gear at the expense of speed.

Damian said...

All this reminded me of this post by Doug at Improper Course, which I see you commented on. I've not yet had the opportunity to use the technique (or rather, I've never remembered at a time when it would have been useful).

Did you ever give it a go?

Tillerman said...

Jeremiah - I don't think luffing head to wind in a Laser would help at all. it doesn't have the momentum of a J/24 and would slow down very quickly.

George - No. That is not permitted on class rules.

Damian. Thanks. I had forgotten that post by Doug. Be like a raw egg! Never did get around to trying it.

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