August 27, 2015

A Gold Medal Performance

By Doug
Bruce in Australia was reading some old posts and sent us comments and questions. These along with my comments (in italics) are reprinted with his permission:  

I've been reading a few of your older posts and was wondering if you could do an analysis of Lijia Xu's extraordinary medal race in the last Olympics? One thing that worked for her, that didn't work in the men's race, was the right side on the beats. In one of the aerial shots there are Lasers way in the background. We can assume that these were the men waiting to start their race. It is interesting that the right side did not work for the men.

She ducked the fleet soon after the start and went right. Was this because she was bailing out and struggling to hold her lane? Usually if you are quick, you stick close to the leaders and match them. For a medal race, she was really taking a risk I thought, but was she? I watched the video again and recall reading that her coach had told her to go right. If that was correct, the risk was not following her coach's instructions.

Her downwind penalty. This rule can be very subjective sometimes. What is your take on her penalty? Was she really breaking Rule 42 at the time? Did she change her style after the penalty? She was still fast! I could not see anything bad, but at 19:00 you could see the judge boat closing in. The announcers said that this was the first yellow flag they had seen so the fleet must have been clean. The call was really picky in my opinion. Thankfully, it did not affect the final results.

After her penalty, she makes ground incredibly quickly to regain the lead. How did she do that in such a competitive fleet? She was lighter than the other leaders, but she also seemed to have picked up some pressure by sailing between NED and GBR. Some call this the 'venturi effect.'

At 20:11, CHI is in the middle perhaps gaining from the 'venturi effect?'
She wanted to go around the right gate but did not have the inside, so she luffed hard and bore away to gain the lead and the mark position. That's not quite how I saw it. She was between NED and GBR about to round the left (or right) gate in second place. At 20:23 GBR tried to cut inside and took CHI's wind, and CHI would have slowed down. So CHI defended by luffing sharply and regained the lead. Great move.

What I find interesting is that the leaders chose the right gate to go left which did not work on the first beat.

When GBR tried to go inside CHI, GBR gave up getting room at the left gate. So why did CHI not simply head for that gate to round and then go right as planned? Luffing two boats, rounding the right gate, and then tacking seemed a lot riskier. And why did GBR give up the left gate?

Would that happen at the front of the fleet in a Masters Worlds? It's very competitive at the front of the fleet. I would not be surprised to see exactly the same moves.

She then gets ballsy and goes right again up the beat. Why didn't she cover? Great question. At 21:27 she tacks away.

Rather than stay with the leaders, CHI does a risky cross to go right on her own.
The factors at that moment:
     ● Cover her competition by continuing left, or
     ● Protect against the boats that were going to the favored right, or
     ● Follow her coach's instructions.

My guess this that she chose the latter, even though it was dangerous because she could easily have fouled NED by tacking. Even on the third beat while in the lead, CHI again chose to go right.

Anything else that for you is significant about her race and what she and her competitors may have been doing differently? Watching the race again, I was impressed by how smooth CHI looked going upwind. The others, especially NED, seemed to be wrestling with their boats.

This was an impressive race because there was a virtual 4-way tie for the gold medal in this medal race. Here's what we can all learn from this gold medal performance:
     ● Have a plan and if you're confident with your speed, stick to it.
     ● Be in shape. CHI did not seem to be breathing at all hard.
     ● Courses now have downwind finishes, so downwind speed rules.

Final comments from Bruce: One thing I had never considered when CHI gained so much so quickly after her penalty was the possibility of the venturi effect. Wow, if that was what it was, it was very powerful. Sure she was the lightweight of the fleet at 60kg but I couldn't imagine her weight making that much of a difference so quickly.

As you say, XU looked so smooth upwind and I also put that down to supreme fitness. She seems quite tallish too, so had great leverage from consistent and seemingly effortless straight leg hiking.

The race was super instructive in so many respects.

August 15, 2015

Kingston Starting

By Doug
People email us updates and questions. Pam and I appreciate this and many of our posts have started with updates and questions like "how do you use your compass?"  I used to give courses for HP in Australia and learned then that one of the best ways to learn is actually by teaching. So, please feel free to contact us using the link in the right column.

We received this from Rod in Brisbane (reprinted with his permission):

I tried your “approach on port and find a hole to tack into” technique in the last two races on Sunday, RQYS. It worked really well, for some reason it seemed a lot easier to see the obvious midline sag and be able to tack in front of the starboard tackers all luffing each other.

It must be pretty challenging doing this in a Worlds-level event though with so many on the line. Do you only do it if it’s a longer than usual line? Do you try to time it to tack onto starboard then just go go go, or tack with still time to luff and defend etc? 

Each location calls for it's own starting strategy. For me, these were the factors at Kingston:
  • The more competitive the fleet, the more risky the port-tack approach. With a world's fleet, it's more difficult at the favored end of the line where the best sailors are because there's a chance that the person you tack below is good at defending and can shut you out.
  • With the prevailing wind from the southwest, there were no line sights looking at the committee boat, so this was another reason favoring a starboard tack approach.
  • There was some current that flowed from right to left. This made starting at the pin very tricky and, in my opinion, too risky. It also made starting at the committee boat really hard because there were others trying to get into the same spot, especially a really good fellow from NZL who was great at judging the current.
  • But starting at the committee boat had one big advantage - being able to escape from a bad start by tacking away and then back again as necessary.
  • But it was a go-left course and the best starts tended to be near the pin which was usually favored.
  • But it's hard to judge the wind on port or in the middle of the line.
  • And I like to circle the committee boat every 2 minutes to get compass readings before making a last-minute decision of where to start.
 Putting this all together, this is what worked well for 14 of the 17 starts that we had in Kingston:
  • Keep making wind readings at the committee boat, leaving all options open as long as possible.
  • If committee boat-favored, try to be right at the boat and go left, but tack into clean air if needed (we have no pictures of this from Kingston, so the following Pam took at the Hyères Master Worlds - I'm 195708):

A warning: if you look closely, there was a platform at the back of this committee boat. As it rocked up and down, this platform went up in the air and then crashed down under the water. I was less than a meter away and it could have damaged both my charter and me. Starting at the committee boat can be scary!

  • If pin-favored, sail down the line watching the line sight staying on top of the sag. When 2/3 of the way down dip below a few boats and then pull the trigger a little before the others.
Like this when it works, blue top on the right.

It’s the great guys such as yourself, Beyer, Bethwaite et al who get there early, and use your experience to experiment for the conditions, pace one another, and reassert that edge in speed, who usually do well. I guess this is a psychological advantage as much as a real speed advantage?

It's both, and it's not surprising that the best people arrive early to practice. This is especially important for people like me who do not have training partners back home. But the best part is being able to practice with the best master sailors in the world. 

PS With your meticulous and fascinating race-by-race observations, I still think your blog is far and away the best Laser blog ever, if not the best sailing blog ever!

Pam and I like to share what we learn and really appreciate when it helps others.
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