Opportunity lost by America’s Cup Defender

With four races scheduled last weekend, America’s Cup challenger Emirates Team New Zealand was expected to seal their victory of the 34th Match. What happened instead was that defender Oracle Team USA won two of three (fourth race was abandoned due to wind limit), but the American team could have arguably won all three. Here’s the set-up:

On the upwind leg of Race 10, the challenger was on the left side of the course, already on port tack and on layline to the north (right) gate. The defender was on the right side of the course, had just tacked to starboard and were on layline to the south (left) gate. The teams were even; the challenger would have to duck.

Here is the broadcast commentary from the video replay (at around 1:41:20):

Ken Read: “Emirates Team New Zealand is going high and slow right now, looking for a dip at the last second. They want to dip and still be able to lay this gate.”

Gary Jobson: “With that tactic, Oracle needs to slow down.”

But Oracle didn’t slow down. They allowed the Kiwis an easy dip, and both teams then rounded the opposite gates at near the same time. The Kiwis went on to win the race.

Ron Young, who was General Manager of the Golden Gate Challenge for America’s Cup 1987, points out the mistake. “Had Oracle done something similar to tactically slow their starboard tack ‘right-of-way’ course, New Zealand (on port tack and thus burdened to ‘keep clear’) would have had no choice but to duck behind Oracle while she was in the ‘circle’ and blocking the north end of the gate. This maneuver would have forced the Kiwi’s north of the gate. Once north of (and missing) the gate, New Zealand would’ve had to tack (or possibly gybe) to follow Oracle around the south end of the gate – likely over than five boat lengths behind Oracle.”

Another option was for Oracle to bear away and aim at the Kiwis, which would have also led to the challenger falling below layline. But this action would have been limited by the ISAF Racing Rules of Sailing – America’s Cup Edition. In Rule 16 (Changing Course), it states that “When sailing to a mark that is to windward, a starboard-tack yacht shall not bear away to a course that is below her proper course and more than 60 degrees from the true wind direction if at that moment the port-tack yacht that is keeping clear by sailing a course to pass astern of her has to immediately change course to continue keeping clear.”

Other options include how Oracle could have tacked in front of New Zealand, which they were entitled to do under the America’s Cup Racing Rules, because they were the inside boat and entitled to sail their proper course around the mark. They also may have been stronger if they were on the starboard layline to the north (right) mark.

The other thought in this is that Oracle had chosen to round the south (left) gate mark, so this discussion is premised on the fact that in hindsight the north (right) mark was preferred, which is often the case due to more breeze offshore, better apparent wind speed due to sailing into the ebb which increases the boatspeed more than the adverse affect of the current, and of course, the starboard advantage if there were a close crossing downwind, as there was.

Bottom line is the defender had the starboard advantage, but did nothing with it.