Thursday 25 October 2012

Rod Davis on recovering AC72 catamarans and crew after capsize

Reposted from sail-world article

http://www.sail-world.com/Australia/Americas-Cup:-Rod-Davis-reflects-on-the-Oracle-nosedive/103149

Double Olympic medalist and long time US and NZL America's Cup crew, skipper and coach, Rod Davis, reflects on on the work that’s gone into the rescue and recovery plan in the event of a capsize…people first then recover the boat

Coach Rod Davis blogs

At Emirates Team New Zealand we have spent a great deal of time studying the Oracle 72 capsize – pitch pole to be precise.



Rod Davis Chris Cameron-ETNZ

Every team has a contingency plan in the event of a capsize and hopes it never has to use it.

The reality is that nothing can prepare crew for the real thing…. and when you are the first, as Oracle was last week, the problem is magnified many times.

Team plans are based on AC45 capsizes and recovery which have been adjusted for the bigger boats which are more difficult to recover. We learned an enormous amount from the Oracle recovery operation.

Here is the hypothesis for capsize and recovery when we launched our 72 back in July.

1. We may be dealing with injuries, possibly significant injuries, as well as the capsized boat. An AC72 is 14m wide and, when a crewman falls, and someone will fall, he will have a good chance to hitting something nasty on the way down. Wing, rigging, wheel, grinder pedestals – something hard.

2. Crew members will be separated from the boat. If there is enough wind to capsize the boat, there will be enough to blow it along on its side, faster than crew can swim.

3. Recover people and deal with injuries first, boat recovery second.

4. The plan for righting the boat is straight forward enough. Just like the 45 'righting' lines, ropes run under the forward beam and attach where the hull and beam meet, on both sides as you don’t know which tack you will be on when you roll her over.



Oracle Team USA capsize AC72 Oct 16, 2012 - Erik Simonson_©_www.pressure-drop.us

The 45s have taught us a lot about righting cats. For example, use a short towline to the righting line, 45 degrees from the high hull down to tow boat is about right. This will allow the hull in the water to dig in and trip the boat so it can be pulled up right. If the towline is too long, the cat will just skip over the water and never 'bite'.

Have strong tow/righting lines, we broke several at Newport, and when they break, they come flying back into the chase boat, so stay out of there, or you will join the injured list.

The quicker the boat is head to wind and righted the less the damage. A problem is two of our three chase boats can’t keep up with the cat in anything other than smooth water.

Top speed to our Protectors is 39 knots. That goes down to 25 knots in waves, for the simple reason crew can’t hang on. The cat is way faster than that, regardless of the sea state. The big chase boat can keep up, but it’s a wild ride.

The fact remains that the two other support boats could be 10 minutes away.



ORACLE Team USA AC 72 capsizes during training in San Francisco Bay and is pushed out of the bay by the tide current as the team try to salvage the platform. - Guilain Grenier Oracle Team USA© Click Here to view large photo

Another tutorial from the 45: Communication is the big challenge. One person in charge, military style, not a 20 people jabbering away on what to do next. Comms to the boat should go through normal chase boat – race boat radios, if the race boat operator is not one of the injured.

One concern is the wing failing when it hits the water. Then the hull falls and lands upside down. People could be under the trampoline which would be roughly 25cm under water and the life jacket is pushing up making it very difficult to swim to the edge.

If you were thinking of taking for life jacket off to swim under water, remember to take off the helmet first…. The life jacket can’t go over a helmet.

Sailors have knives to cut their way though the trampoline allowing a direct escape to the surface. They also have individual air bottles to breathe while they get things together. They have trained with the air force on how to keep it all together and not panic. Apparently helicopters go upside down when they crash into the sea, so they boys trained in the air force pool to prepare.

On the tender, the one that can keep up, an experienced rescue diver is suited up.

What did we learn from the Oracle capsize?

Making a head count is difficult and takes time. Clearly you need to account for everyone and count twice so there is no mistake. First you need to know who and how many people are on board (we often have extras: sailmakers, wing designers, etc)



ORACLE Team USA AC 72 capsizes during training in San Francisco Bay and is pushed out of the bay by the tide current as the team try to salvage the platform. - Guilain Grenier Oracle Team USA© Click Here to view large photo

Helmets are numbered but they are not sequential. Dean’s number is 14 and Dalt’s is 46. The boys will be scattered around, all dressed in black. It’s like counting rugby players but they are not all on the field, some are on the sidelines and in the stands. A buddy system will help but a head count will still take time.

When training we can’t take off downwind for 20 miles or there will be one chase boat on the seen. Six miles is ok as the legs for the America’s Cup are less than that.

Thankfully and miraculously there were no injuries with the Oracle capsize. To identify the injured, we use international hand signals. Hand on top of your head is 'I’m OK'. Hand up 'I need help.' Those who are OK are to swim into groups and wait there; the dry suit and life jacket means you won’t freeze or drown. Someone will pick you up.

The paramedic will assess injuries; depending on how many are hurt and how serious others are he might leave an injured man there while he attends to more urgent cases.

Once the people are under control the focus changes to the boat. Oracle’s wing survived the initial impact but the boat was sitting nose down, making it hard to right.

Somehow they got the boat on its side and attempted to right it. The Oracle chase boat and support teams are as good as any in the world, so it not a case of should have done this or that, it’s on-the-job training.

We think there is a window of about 10 minutes after a capsize when there’s a good chance to right the boat. After that chance of righting falls dramatically.

The wing will hold out the water for only so long. To add to the problem the down hull will start sinking. Oracle went partially nose down, as the water in the 'down' hull went to the bow. That makes it very hard to right.

Water tight bulkheads and flotation at the top of the wing will buy time, and extend the 'window'.

Plan A is to right the boat, plan B is the stabilize it and then tow to smooth water to asses our next move. The last option is the separate the wing and boat to bring them in separately. That sounds simple but if the boat is on its side, you can’t really get the wing off without the boat falling upside down.

No question it will be a mess, and you plan for the worst and hope for the best. Chain of command is all important, because there is one thing I am pretty sure of: we are going to see more 72s capsize.

Final word from Grant Dalton: I hope that Rod’s last sentence is wrong.

by Rod Davis

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