Catamarans Damaged by Cyclone Ului

[Kordie]

Originally Posted by Eleven

My own input:- Hang a weight, spare anchor whatever on a loop and slide it part way down the anchor rode. This will help to take a lot of the snatch loads off the bows and rode, and off the anchor, as the boat pitches.
.

That is called a Kellet.

They are discussed in some depth in the two links I posted earlier.

[Jim Cate]

Not wanting to start a bun fight, but those catamaran bows sticking up out of the water (a sad sight indeed) do put some pressure on the "unsinkable catamaran" statements often seen in these pages.

How did it/can it happen?

Jim

[downunder]

Jim,

Clearly all cats are not borne equal. That why I need to find out what happend to those vessels. One was a Seawind & have not yet determined the one floating bows only. Hopefully eventually get more info on what happen to them. Quite possible if moorings failed and were driven against the WRAY jetty/pontoon holeing them significantly. Those cats certaintly did not have enouge watertight compartments to do the job in particualar at the stern.

It will be useful to find out more to help me in searching for a cat for my purposes.

[44'cruisingcat]

Originally Posted by Jim Cate

Not wanting to start a bun fight, but those catamaran bows sticking up out of the water (a sad sight indeed) do put some pressure on the "unsinkable catamaran" statements often seen in these pages.

How did it/can it happen?

Jim

If you build a cat out of a non-bouyant material, ie solid glass or aluminium, it can sink. Especially as has been said, if it doesn't have enough watertight compartments, or if too many of them are breached.

Most modern cats are built using foam or balsa cores. Most have numerous watertight compartments. They are far less likely to be able to sink.

[downunder]

Kordie,

References you supplied were excellent but there is no way I will use rope around coral. Schute Harbour where many vessels were damage has plenty of coral on bottom. You may get away with rope on sand but not around coral reefs.

Of course it is advisable to have plenty of spring in a bridle to take shock loading out. Maxing Out's website has an excellent diagramme.

ALMOST NEVER FAIL CATAMARAN ANCHORING SYSTEM WITH A BUEGEL ANCHOR*** Exit Only performed the first half of her circumnavigation

[downunder]

Nick,

Great to get your input and real world experience.

I am without a vessel at present but planning for a cat to retire into the Pacific on having lived my 60 years with motor vessels diving the GBR & Coral sea. Lot to learn re sailing but principles of seaworthness similar.

Not sure how good the forcasts and tracking is in your part of the world but in Australia our system has improved greatly over the years and the tracking of ULUI was the best we have seen with plenty of warning to move North out of the area of influence or get into mangroves.

Risk management principles.

1. eliminate hazard - move out of the area. BEST
2. If can't do that need to look at most effective way manage the blow.
3. Advantage of a cat with low draft is you can always get well into mangroves and tied down and as you suggest remove sails and dingys.

Here in Queensland I would prefer to be in mangroves than on hard with missiles around. If no local knowledge explore with dingy first.

It is 30 years since the Whitsundays had a good blow although there have been a number of close shavesand some lesser storms. There has been a massive increase in the number of vessels and owners who have not been bought up in cyclone areas and this certainly showed in their lack of proper preperation.

[Kordie]

Originally Posted by downunder

Kordie,

References you supplied were excellent but there is no way I will use rope around coral. Schute Harbour where many vessels were damage has plenty of coral on bottom. You may get away with rope on sand but not around coral reefs.

Of course it is advisable to have plenty of spring in a bridle to take shock loading out. Maxing Out's website has an excellent diagramme.

ALMOST NEVER FAIL CATAMARAN ANCHORING SYSTEM WITH A BUEGEL ANCHOR*** Exit Only performed the first half of her circumnavigation

That is a great website you steered me to. Thanks mate.

The simple anchoring diagram shown there seems to incorporate many of the principles mentioned in my earlier reference. Also keeps the elastic rope part of the rode off the seafloor where, as you described, the coral makes short work of it.

The bridle I used in the Whitsundays (not my boat) was just a metre or two in length and only served the purpose of keeping the weight of the anchor off the windlass - it would have provided no elasticity to the whole rig.

Thank you to everyone who has contributed. I feel I understand so much more about anchoring. There was a time when I thought an anchor was just a weight to hold the boat from drifting away - can you believe that?

Simon

[downunder]

Simon,

I look at it this way. More vessels are lost through inadequate anchor systems than any other. Just look at Schute harbour last week as an example. It is a wonder insurance companies don't look closer at this.

Most small powerboats and recreational ships for example have the minimum 2 meters of chain required by th govt regs.

http://www.msq.qld.gov.au/~/media/ms..._equipment.pdf

[s/v Jedi]

Originally Posted by downunder

Not sure how good the forcasts and tracking is in your part of the world but in Australia our system has improved greatly over the years and the tracking of ULUI was the best we have seen with plenty of warning to move North out of the area of influence or get into mangroves.

Forecasts are excellent in the Caribbean. The problem is that hurricane paths are totally unpredictable. During Ivan in 2004 some boats believed the forecasts and moved their boats straight into the hurricane while they would have been fine if staying put.

Also, it is typical to be light to no wind at all before the hurricane arrives so any moving out has to been done with diesel.

3. Advantage of a cat with low draft is you can always get well into mangroves and tied down and as you suggest remove sails and dingys.

The draft is an advantage but the beam and light displacement are disadvantages. Many of those channels in the mangroves are too narrow for a cat. Being light displacement means not just holding it in place but also holding it down. Cats and tri's went airborn during Ivan and one tri was discovered up in a tree!

It is 30 years since the Whitsundays had a good blow although there have been a number of close shavesand some lesser storms. There has been a massive increase in the number of vessels and owners who have not been bought up in cyclone areas and this certainly showed in their lack of proper preperation.

There's more to it... Grenada didn't have a hurricane since Janet in 1955 so they were totally not prepared. After Ivan their consensus was that it would take at least another 50 years before the next one strikes so they were unprepared when they were struck the next year too. Most people are naive and refuse to think about the possibility that something bad can happen in general (storms, pirates, volcano eruptions, earth quakes etc.)

ciao!
Nick.

[Tropic Cat]

The post mortem on boat damage during the devastating 2004 hurricane season here in Florida, focused on inadequate anchor rodes or rode protection as a significant factor. Admittedly, the report did not comment on advance boat prep in reducing windage.

During hurricane winds the lines failed due to three types of chafing. First, the obvious where rubbing violently on some part of the boat eventually destroyed the rope.

2nd, heat fatigue where the repeated stretching of the polyester lines caused excessive heat build up and literally melted the lines from the inside out.

Lastly (and this is somewhat speculative) is that salt crystals embedded in the rope twist became miniature saws that contributed to the line's failure under extreme stressing.

The report also commented that our tried and true 3 strand nylon lines parted much more frequently than double braid which offered increased resistance to chafing.

They also observed that boats with all chain rodes had them break out of their fair leads and acted like steel saws on plastic boats.

The report went on to say that all boats caught directly in the path of the hurricanes were damaged to some extent, regardless of preparation.

As Nick has already mentioned the best protection is to get out of the area, get hauled out, or find the mangroves (or a canal) and spider the boat.

[Eleven]

Thank you, Tropic Cat. Very useful info from an experience we all hope will never happen to us, but we are more confident knowing what the right thing to do is, and what's wrong with our current set up.

[SelkirkWind]

Originally Posted by s/v Jedi

It's time we all start to understand that mono hulls and multi hulls are different concepts and it's just not possible to say one is overall better or worse. The strengths of each design are also weaknesses in different circumstances. They are all a compromise.

ciao!
Nick.

So true Nick!
Chip

[Tropic Cat]

Agreed

[imagine2frolic]

It's time we all start to understand that mono hulls and multi hulls are different concepts and it's just not possible to say one is overall better or worse. The strengths of each design are also weaknesses in different circumstances. They are all a compromise.

ciao!
Nick.[/QUOTE]

Yes, I have to agree with this, and have said it numerous times. They are 2 different beast, and we all make some kind of compromise when we make our choices. There are some clunker cats as well as some clunker monos..................i2f

[44'cruisingcat]

More of the damage done by Ului

The Coastal Passage Report-Cyclone Ului

Cyclone Ului, or Deja Vue again