COOK STRAIT Weather

[exfishnz]

This is the Police Rescue 17m (55') monohull[1] "Lady Elizabeth III" (based in Wellington). She is purposely designed to be watertight & self righting at 180 degrees[2]. She's been out in large sea conditions in the Cook Strait (i.e. the sea's on the youtube vid at the beginning of this thread).

[1] There are large Police cats in NZ, but none that I know of for use in the Cook Strait.
[2] Her predecessor was capsized with the loss of 3 officers (thus this vessel was designed).

(click pic to enlarge)

[exfishnz]

Originally Posted by 44'cruisingcat

Yeah and you couldn't in a mono... I'm out of here.

:kissy:

[MidLandOne]

A start on Lady Liz 3's replacement is actually scheduled for 2009-2010.

I used to have a little video of Lady Liz 3 undergoing self righting trials after she was built but I can't find it now to put it up on here. She was rolled over in Nelson harbour with a crane - complete except for the antennas which were removed.

She is actually an almost direct copy of a Danish design with the main difference, if I recall correctly, just in the higher flared bow.

[exfishnz]

Originally Posted by MidLandOne

A start on Lady Liz 3's replacement is actually scheduled for 2009-2010.

Got any info (or links) on the new vessel?

She was rolled over in Nelson harbour with a crane - complete except for the antennas which were removed.

Not many multi's can do this

(click pic to enlarge)

[Alan Wheeler]

Although to be fair, not many Mono's can either :-)

[badlattitude]

Originally Posted by exfishnz

A place only for mono's???

Attachment 3916

A video of the M.V. Suilven, a “roll on roll off” (& cattle) cargo ferry negotiating into the Cook Strait passage. Note the puff's of black smoke coming from the stack that would indicate the increase of propulsion power to keep the bow into the waves (i.e. help avoid broaching). Also note the frequency & breaking of the waves, probably not something you'd want to deal with in a flipped multi.

Length: 283'
Gross tonnage: 3,638

Have negotiated these waters myself in smaller fishing vessels. Furthermore, Mr Alan Wheeler has done so in his full keel mono.

Prepare for the worst, hope for the best. Murphy's law is that whatever will go wrong will do so at the worst possible time.

Fallado, a 44 foot catamaran negotiated Cook's Strait twice, while doing a figure 8 circumnavigation of New Zealand.

Website: Fallado's Circumnavigation

It appears the area didn't impress them enough to even mention it on their website. It also failed to deter them from continuing on to circumnavigate the globe, going westward round Cape Horn.

I feel that seamanship is likely more important than the number of hulls in situations like the one shown in the video.

So I ask - what would be the best tactic for a 40 foot heavy displacement steel monohull in conditions like this?

[exfishnz]

Originally Posted by badlattitude

It appears the area didn't impress them enough to even mention it on their website.

Well then, it must of been a very calm day in the Straits for their passage.

So I ask - what would be the best tactic for a 40 foot heavy displacement steel monohull in conditions like this?

You don't know??? Simple, either punch into it, or run with it (& possible use of a drogue if needed).

[Alan Wheeler]

Badlattitude, no one is saying that you can sail across or ion or around the Cook straight in a multi. I am sure many have and will continue to do so with no problems at all. Even on ruff days, I am sure that a multi would cope just fine. And no one has even said that a Multi could not handle a really ruff day. I am sure a Multi will even handle the real ruff stuff. But what I did say was that I would not want to be in the middle of the straight in a Multi in a realy ruff Cook straight storm due to the fact that every multi I have been on (and yes I have been on many multi's of all types and sizes and propulsion) ruff weather has made their ride very uncomfortable.
My post has been taken out of context. Please read the general conversation we were having at the time and my coment in context with that. If you did not understand it that way, then I am sorry I am a poor communicator with words.

[badlattitude]

I must have misinterpreted the titled of the thread.

"A place only for mono's?" does seem to be quite unambiguous though.

I just wanted to point out, that contrary to what anyone reading this thread might have been lead to believe, at least one multihull has traversed Cook's strait and survived. Twice in fact.

No doubt, as you say, there have been many more.

[badlattitude]

Originally Posted by exfishnz

Well then, it must of been a very calm day in the Straits for their passage.



You don't know??? Simple, either punch into it, or run with it (& possible use of a drogue if needed).

It must have been two very calm days. They passed through twice.

No, I don't know everything, not everyone does. I've never sailed my (monohull) boat in conditions like that. Nor do I ever want to.

However, from my limited experience, I'd say that keeping the bow pointed directly into that kind of sea, and presumably very strong wind, would be far from simple, especially in a modern, high freeboard, relatively lightweight boat.

In keeping with the first post's theme of "hope for the best, prepare for the worst", what would be your recommended tactic in these conditions, if your engine wouldn't start, and you had insufficient searoom for running with the waves?

[exfishnz]

Originally Posted by badlattitude

I've never sailed my (monohull) boat in conditions like that. Nor do I ever want to.

Ironically, its actually not scary, its more a PITA. I don't say that to be "macho", I say it from personal experience (as I was raised on these waters). The main thing is to have control of your vessel & faith in your seamanship abilities.

keeping the bow pointed directly into that kind of sea, and presumably very strong wind, would be far from simple, especially in a modern, high freeboard, relatively lightweight boat.

My previous answer was given to your previous question of "a 40 foot heavy displacement steel monohull". In a light vessel, IMHO, run with it (& possible use of a drogue if necessary). If for some reason you can't run with it, then hopefully you've carried a parachute (sea anchor) with a very long & strong rode.

Going "head on" into sea's like this with a heavy vessel is not a major issue. Most of the trawlers/trollers I've been on have the hp & heavy duty hydraulic steerage systems to handle it. However, those vessels are built for these types of waters (similar to North Sea, Alaska type vessels etc).

what would be your recommended tactic in these conditions, if your engine wouldn't start, and you had insufficient searoom for running with the waves?

If you're out there then your diesel is already working, but if it fails[1] (for some reason), or you can't run with it - then best preparation would be to carry a parachute.

[1] Its very unlikely that a diesel would fail (once started), but like everything else - it is possible.

Edit (of my own quote):

If you're out there then your diesel is already working

This would only apply if one's vessel was already under power.

[Alan Wheeler]

into that kind of sea, and presumably very strong wind, would be far from simple, especially in a modern, high freeboard, relatively lightweight boat.

The steering is not so much the issue. I had OK control. Please note, I was not under sail for this trip. I do think if I was able to have even the headsail up, the trip would have been much more comfortable for us having that stability. Not enough Hp would be a problem in the conditions I was in. In these conditions it is more prudent to use the thicker end of the rule of thumb on Hp/T. However, the real issue is slowing the faster flat modern hulls down and I am talking about monos here. Even with my much heavier(26T) slower boat, the biggest problem I had was trying to stop being launched into the air and free falling off the backs of the waves.
We maintained a normal and constant throttle. This gave us forward momentum, but still at a slow speed. I had the dilemma of wanting to get through and out of the crap and still not head to fast into it. The major concern we faced was meeting the crests just as they broke at the tops. Maybe partly because we have such huge bouyancy in our bow section, but these things simply smacked us and flicked us up as the wave ran under us. That short "Air time" was enough to have us then drop over the back of a steep wave. Depending on how that break smacked us, determined that attitude we would take as we went over the back. Sometimes we would be upright, sometimes we were as much as 45-50 degrees on our side and that was the most uncomfortable way to fall.
Coming back and thus running with it the next day, the big swells were still there, but the ruff stuff was completely gone and we didn't have anywhere near the same ruff ride. Still very humbling mountains of water, but quite a different experience.
If I was not intent on getting into port, as in, if we hit weather like this off shore, I would think I would approach things in a very different manner. Certainly trying to put up with conditions like that would have been exhausting and so trying to make the ride more comfortable by hoving too or running with a drogue would be the better method.

[exfishnz]

In regards to punching into large waves:

When punching into a large wave, before you reach it, you want to make sure that the bow lines up to the wave. Now, before you hit it, you back off the rev's (& warn the crew to brace themselves), this allows the vessel to ride over more easily than flying through the wave trough. Sometimes the waves are so big & the trough's are so deep that you can't avoid flying through them (in that case , hold on very tight ). Now, once you go through the wave, you need to put the hammer back down & line the bow up for the next wave, & so on, & so on etc etc. In this situation, you may or may not be manually steering, it really depends on how well (quickly) your vessel's bow lines up to the waves.

In the same situation above except in night time, you need to keep a really good eye out for the waves that are cresting (beginning to break) towards your vessel. Generally you can see them in night (as they're white), but obviously with limited moonlight &/or heavy overcast its going to be harder.

In regards to large & deep trawler type hull's, they just go a bit slower, they're not too concerned with trying to ride over the waves. They're so deep & heavy, that when they smash into them, they actually feel like they've hit something & you kinda fly forward a bit (if you're standing)

Once you get the feel for how your vessel handles in these conditions, then it all becomes second nature.

[Zach]

I'm in a bit of awe.

My atomic fours prop was lifting out of the water in a steep 4 foot chop enough to slow to 1 knot! I sure hope that the boat thinks its powering through flat water... uphill!

(I've got goose bumps...)

[Weyalan]

For what it is worth, the 3m significant wave height restrictions on the Incat wave piercing catamarans are not necessarily the limit of the performance of the ship, but are the limit for the type of lifesaving/evacuation equipment installed on the vessel. Liferafts and slides on the Incat boats have been tested in accordance with the Heavy Weather Sea Trial requirements for vessels operating under the HSC (High Speed Craft) Code, which basically means fully ballasted testing in 3m significant / 25 knots. Having participated in several such sea trials, let me just say that even in these by no means extreme conditions, it ain't an awful lot of fun.