sail-world.com -- Gladwell's Line: Port Entry pre-determines most race outcomes
Gladwell's Line: Port Entry pre-determines most race outcomes
Mon, 23 Sep 2013
Oracle Team USA got the jump at both starts in Races 14 and 15, today, and crept two points closer to staging one of the the great comebacks in world sporting history.
However the regatta remains locked on Match Point for the Challenger, Emirates Team New Zealand.
All last week, in response to questions as to whether they were down and out, Oracle Team USA skipper, Jimmy Spithill infuriated the international media by repeating the line that they only had to win one race at a time, that he was very excited by the challenge that was ahead of the team, and how positive and hard-working the team were.
What seemed to be a over-optimistic recital of the Oracle Team USA party line, now seems to have a lot more depth to it.
Certainly the teams fortunes have changed dramatically since the switch-out of tactician John Kostecki, and his replacement with celebrated Olympic Medalist, Ben Ainslie – whose combination with Tom Slingsby seems to grow by the day.
What has changed?
Probably not as much as the results would tend to indicate.
For sure Oracle Team USA made changes to their boat. At the Designer Forum last week, Oracle Team USA’s Dirk Kramers said they had made five key changes. But wouldn’t name them. His counterpart, Emirates Team NZ’s Nick Holroyd, could only pick three of the five, and in doing so let slip that both teams were working hard on their daggerboard systems. Mast rake was another area that Holroyd picked up.
With the racing now occurring each day, and with one team on Match Point, Oracle Team USA effectively has little to lose by playing the bold moves, and buying all the time they can.
An analysis of the racing, and indeed what was suspected to be Oracle’s game plan all along was to focus on downwind speed (that being four legs of the five leg course) and then try and hold on upwind.
Oracle seemed to have made a mis-calculation in the opening days of the regatta when they had traded off too much upwind speed, for the downwind gain. And had not factored in the New Zealander’s ability to be able to do foiling tacks and accelerate out of tacks very quickly.
Couple that with the tide that prevailed for the first week, and Oracle had no answers – even if they were ahead at the bottom of Leg 2, as Emirates Team NZ could use the incoming tide to pull the Defender over to the City side of the course, initiate a tacking duel and work their way through by the mid-point of the course.
Watching from on-the-water it was just like watching a clock ticking down – it was only a matter of time before they broke through. You don’t see the continuity of what happens on television due to the switching of the shot angle and the pull shot, which distorts distances.
One race Oracle did win, was when they rounded with a larger than normal lead, could afford to apply a loose cover, and avoided the need to engage with Emirates Team NZ.
That was Week 1.
Week 2, the tide changed, with the ebbing or outgoing tide allowing Oracle Team USA to sail the full width of the course, able to tack in their own time and avoid the tacking duels with Emirates Team NZ.
This week, Week 3, the incoming tide is back – constraining the width of course able to be used. And Oracle has two new tricks in their bag – being able to foil upwind – in the way that Emirates Team NZ were able to do with devastating effect in Week 1, and the already discussed foiling tacks. Maybe they are still not as slick in their crew-work as Emirates Team NZ, but certainly the gap has closed.
The advantage of the port hand entry into the start box is proving to be decisive.
In Week 1, this wasn’t quite such a factor, given that Emirates Team NZ had the ability to reel in any advantage that Oracle Team USA, once they turned the corner at Mark 2. And if the Kiwis led at that point they were just devastating.
In Week 2, we had the outgoing tide coming into play. This allowed the team with the port entry, (and early entry) to be able to get up-tide of their competitor and then control the start. This is done by one of two ways – sailing the shortest distance to Mark 1, getting the inside rights at the mark, and then going into the run with a lead of 40-80 metres. From there it is a matter of defending to the bottom of the course, and then covering up Leg 3.
The other strategy with the Port entry position is that it allows the leeward boat to elect not to sai the shortest course, but instead push up on the windward yacht, who must keep clear. There are a myriad of variations on this strategy, but Spithill’s favourite seems to be to sail high, outside the three boatlength circle, luff the Challenger towards the Golden Gate , and then pick your moment to bear off for Mark 2.
On TV you don’t see the subtly of this move, and the fact that the windward boat has no option but to follow. It is all about timing and accelerating. But on the water it is just a matter of watching an inevitable outcome, as again the Port entry boat goes in with a lead of 40-80 metres at the first mark.
In Week 3, we are back to the Week 1 scenario with the tide. It is coming into San Francisco Bay, so there is no push up under the windward yacht, but still the option to either take the shortest route to Mark 1 remains; or to push the other boat to windward. Either way the port entry boat will be first, unless they make a serious tactical or timing error.
Once the port tack entry boat has the lead it is not easily lost – with the old match racing truism applying – that it is easy to catch up but difficult to pass.
Barker did find a counter to the Port entry advantage, by trying a timed start and sail over the top of Oracle Team USA, it worked – but the race was blown up because of wind limits – and the Oracle afterguard will not let that happen again.
Sure, some media will quote numbers that the numbers are almost even for the port hand entry advantage, saying that only eight out of 15 races have been won by the port hander. But that ignores the upwind advantage that Emirates Team NZ enjoyed in the first week, and since that degree of edge no longer exists. Neither is it supported by the analysis below.
But even so, at this current level of competition, you can’t give your competitor a 40-80 metre lead going into the first downwind leg and expect to just fly past – unless your competitor makes a major tactical error on the next three legs.
In the table below the races have been analysed using Virtual Eye to ascertain which entry side is going on to win the majority of the races. As the 34th Match has evolved, the starting styles have changed as the race analysis has been done. Now the inside boat virtually controls the way the first reaching leg will be run, however the outcome is almost always the same.
Initially proposed as a means of making the racing spectacular, the reaching start on Leg 1, virtually means that the draw for the entry side virtually determines the race outcome, by handing the port entry, or inside boat a lead of one to three boat lengths at the start of the first downwind leg.
Winning Team/ Entry Side
Leader at M1
50 metres to ETNZ (P)
ETNZ went on to win
43 metres (S)
ETNZ to windward jumped OTUSA at start
86 metres to OTUSA (P)
OTUSA had Port entry
102 metres to OTUSA (S) – effectively a P entry
OTUSA managed to get inside ETNZ and gained benefit of
77 metres to OTUSA (S)
OTUSA drove through to windward
132 metres to OTUSA (P)
ETNZ passed OTUSA on Leg 2
38 metres to ETNZ (S)
ETNZ sailed over the top of OTUSA
50 metres to ETNZ (P)
ETNZ near capsized on L2 allowing lead change.
71 metres to OTUSA (P)
OTUSA extended to a lead of over 200 metres at the end of
Leg 2 and went onto win.
58 metres to ETNZ (P)
ETNZ took OTUSA outside 3BL circle at M1
40 metres to ETNZ (P)
ETNZ sailed high, and then broke to lead to M1
77 metres to OTUSA (P)
OTUSA extended to a lead of 150 metres at the end of Leg 2
29 metres to ETNZ (P)
ETNZ penalised/passed on L2 when in the lead.
85 metres to OTUSA
OTUSA extended to a lead of 300 metres at end of Leg 2
40 metres to OTUSA
OTUSA extended to a lead of 700 metres at the end of Leg 2
in a patchy breeze