Monday, February 25, 2013

Start Near the Favored End

SailX, the online interactive regatta racing game and virtual trainer, is currently running a weekly series of training videos by one of the best sailors on SailX, a fellow who goes by the name of "flow". It turns out that flow is, in real life, Steve Hunt, a well known American professional sailor and coach. Among other achievements he is a seven-year member of the US Olympic Team in the 470 Class, two-time Etchell World Champion, and Congressional Cup Winner.

Flow certainly knows his stuff when it comes to teaching mere mortal midfleet mediocrities like me how to sail smarter and faster, and SailX is an excellent visual tool to support his teaching. So I thought I would write a few posts linking to his lessons, and supplementing them with my own ill-informed and insane ramblings just to confuse my readers.

The first lesson in the series is about starting near the favored end of the start line...

In the first race, the pin is only favored by about 5 degrees and flow mentions that there appears to be more wind on the right hand side of the course. (The darker shaded areas mean more wind.) The questions I asked myself were (a) would I even be able to spot a 5 degree bias on the line? and (b) would it really be worth going for the pin in that situation?

Flow doesn't make a very well-timed start at the pin (he was distracted talking to us) and it certainly looked to me as if two other boats ESP-500 and notainslie got better starts near the middle and right half of the line and were more or less even with flow up the beat. Flow was also lucky in that no other boat seriously contested the pin with him. It's not always as easy as he makes it look here to win the pin and then tack and cross the fleet!

So let's do the math...

It looks to me as if the start line is about 25 boat lengths long. If we assume these are 15 foot dinghies that means the start line is about 375 feet long. If I remember my high school trigonometry correctly that means the the pin end of the line is about 33 feet to windward of the boat end, or just over two boat lengths. Which means that you are only one boat length further to windward than the boats in the middle of the line.  Is that a big enough advantage to be able to tack and cross them, assuming you all get equally good starts?


In the second race example (clip starts at about 3:35) the pin is 8 degrees favored, and flow goes for the pin again. This time he has a group of boats just to windward of him on the line but he still manages to tack at the pin and cross them. Based on my math that shouldn't have been possible but I think he pulled it off because he was going faster at the start and was closer to the line at the start than they were. The tack (in a Laser) didn't cost him much and he just managed to cross the whole group. Not sure I would have had the balls to attempt that move in a real race!

The wind is clocking right and there is more wind on the right, but because of his tack at the start, flow is sailing into the stronger wind with the other leaders and is looking in good shape again.

He makes it look easy.

In real life (and in SailX sometimes) going for the pin like that can be a high risk/ high reward gamble. Sometimes several other boats have exactly the same idea and there can be a huge pile-up at the pin with perhaps only one or two boats coming out of the mess cleanly. In such situations it can be safer to start a little farther up the line.

Part of the skill in deciding what to do depends on "reading" the intentions of the rest of the fleet. Is a whole bunch of boats going to fight for the pin or are they all hanging out near the boat (as in the first example)? That's one thing I currently find hard to do. If I commit to a place on the line too early it sometimes turns out to be a bad choice because that's where the crowd chooses too. If I watch what the fleet is planning to do too long, I can leave it too late and there are no holes left.

I guess I need to practice on SailX more.

So what do you think?

How would you have handled those starts?

Do you think SailX is a useful training tool?

You can find all the videos in the Steve Hunt coaching series in this SailX article.


Abe said...

I agree with Flow that the way to win a series is to always be in the top group of boats. But the consistency only comes from avoiding big risks. Starting at the pin of a five or even ten degree biased line when the breeze is in a left hand phase, hoping to be able to tack and cross the fleet is a big risk with little potential reward. Freedom to tack is a huge advantage and the boat at the pin is throwing it away.

I had enough trouble remembering my high school trigonometry even when I was at school, let alone now. But it would be interesting to calculate how long it would take a boat starting at the unfavoured end of a five degree biased, 375 foot line to negate any gains made by a boat starting at the pin, if the boat starting at the boat end was able to tack immediately while the boat at the pin had to continue sailing into the five degree header. I bet it wouldn't take long, with the added advantage (assuming an oscillating breeze) that the boat to the right will get the next shift first.

Chipping away with lots of low risk, small gain moves will produce a much better end result than going for the high risk, high return moves. Jordan Spencer said it much better than me in the Australian Sailing mag a couple of months ago:

Tillerman said...

Excellent points Abe.

And I think the risks of starting at the pin are even greater on a short course race such as in SailX. I can remember many times in SailX when I have started near the left end of the line with a bunch of boats immediately to my right and been unable to tack until they all tacked. (Of course I could slow down and duck them but that loses a lot of ground too and is probably not worth doing unless there is a huge advantage on the right.) Quite often one boat who doesn't appreciate the reasons for a tack will drive a group of boats out to the left corner, or even beyond the layline before tacking.

Of course in a large fleet on a long start line the advantage of being near the favored end of a biased line is much greater.

Noodle said...

Tacking right at the gun sure seems like a great way to discard a two boatlength advantage gained by starting at the favoured end. Starting on port tack would help.
However, in light winds those gusts lurking on the right side will probably be more valuable than a 5 degree advantage.

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