James Spithill Buries AC45 in Fleet Racing
October 6, 2012
Near the front of a tightly packed fleet of AC45s, Oracle4 began to
bear off at high speed, a maneuver which loads up the leeward hull,
pressing it lower in the water. Above, the port bow is submerging at speed. Within a certain range this is
normal behavior on a cat at high speeds, and the buoyancy and normal
pitching of the boat helps to recover while barely slowing down.
Photo:©2012 Chris Cameron/ETNZ
Photo:©2012 Chris Cameron/ETNZ
Go too far however, and the bow digs in, the trim of the sails and the force of fast-moving water over the top of the hull keep forcing the hulls down. Oracle4 had been flying the windward hull, but deceleration and the start of the dive brought the starboard bow down to the water, too. The question is whether she can lose her forward inertia before passing the point of no return. The wing sail has been eased, but a hard sail can't be depowered as quickly as a soft sail.
What is saving the boat in the image above is the massive forward volume of the AC45 hulls. The water is acting as a brake, but the forward buoyancy is also helping resist an even steeper dive that would flip the boat forward. Most catamarans in this situation would have pitched violently onto their bows if they got into this attitude at speed. If the boat had been heeling more and caught only one hull, rather than flipping straight forward it might instead cartwheel.
Artemis, at left above, was trailing behind and aligned slightly to port of Oracle4 and had to change course to avoid ramming them as Oracle4 stopped. Artemis herself had boats behind her and to windward and to leeward. Passing to leeward was the easiest out, and even if it were possible to go to windward, heading up too sharply risks heeling their mast in the turn, which could strike Spithill's boat. The Swedes are in the process of bearing away to get below Oracle4.
Photo:©2012 Chris Cameron/ETNZ
The boat has slowed, as the loss of the spray shows, and Oracle4 narrowly avoids being flipped over her bows. Note how much higher the hulls float in the water compared to the previous image. With Oracle4 pitched up on her bows, though, now the windage on the rig and platform will take effect along with the tilt to port and she will fall onto her port beam. China and Energy are okay to pass to windward of Oracle4, but Artemis just out of frame to the left is still in her bearaway to avoid a collision. Behind Artemis, Luna Rossa Piranha then had to bearaway to avoid hitting Artemis.
Artemis was astern when the incident started, and after the hard
bearaway comes back up to course, trying to pass to leeward of
Oracle4. Spithill's boat, however, is falling away to port now,
and Artemis narrow escapes getting entangled as they pass. Photo:©2012
Chris Cameron/ETNZ
Oracle's boat falls over at a quartering angle, the wing mast about to
strike the water alongside Artemis. This was still a very
dangerous situation, and fortunately the timing and the angle as the boat
fell left Artemis just clear. Photo:©2012 Chris Cameron/ETNZ
Photo:©2012 Guilain Grenier/Oracle Team USA
In the aftermath, the crew was safe, though with a few injuries, cuts, and
bleeding. The boat was righted without significant damage. The crew went
on to place second in the next race. The scenario of a leading
boat capsizing in the middle of a tight fleet was one of the more
dangerous situations that could be anticipated with these boats, and
that collisions and serious injuries were avoided is a credit to the
awareness and boathandling of the crews, and testifies to the rising
skills in the AC45 fleet. A lot of people had to make good
decisions and execute them in a matter of seconds. Would they
have been ready to handle their boats like this in an early regatta
last year? Luck is a factor, too.
Photo:©2012 Chris Cameron/ETNZ
Links of Interest:
Day 4 highlight at
America's Cup YouTube Channel showing capsize