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Old 30-07-2017, 13:51   #106
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

^^^^^^
Yes, we've been calling them computer assisted groundings since about 1992. The images are so precise people tend to believe they're reality, rather than a fallible representation.

A prudent navigator takes a lot of variables that don't show well on the computer and blends them in with his practice, consider the large swell, consider the tidal set across the shallow reef, and so on.

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Old 30-07-2017, 14:16   #107
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

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Originally Posted by Pascals Wager View Post
Cormorant I agree, was surprised by the difference that the CMAP image provided. From a human factors perspective certainly significant. It hasn't been long since this unfortunate accident and sadly some in the community are quick to criticise and even confidently state the cause. There's a lot to be learnt here and of merit is the owners openess to share their disaster to the rest of us via their blog. I guess the crew of Vestas Wind lacked experience and seaman ship ,how did they ever get Insurance??
Vestas was RACING. All caps for emphasis and not to be obnoxious. When racing, the risk tolerance goes up significantly. That said, the Vestas navigator has admitted that he f**ked up. There were gaps in the reef and he missed. But the competitive advantage in racing of cutting corners has no place in cruising. (Though of course there are some exceptions to that, for example racing a storm into safe harbour.)

I am not criticising and I certainly empathise with the family. But the lessons that can be taken from their frank disclosure are clear and relate directly to navigation skills and seamanship. I am taking their narrative at face value and assume that if there were other factors, those factors would have been mentioned.

Regarding the Navionics map, I guess it depends on your version. Here's what I see: fringing reef is clearly shown. In any case, the family had likely been using the same chart system their entire time on their boat, so surely they were familiar with the interface and had already seen in French Polynesia the difference between chart view and real view?
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Old 30-07-2017, 14:19   #108
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

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Originally Posted by mbuckely View Post
I was in this bay on Huahine two days after this family hit the reef. Spoke with two of the kids for a bit. Nothing in depth. Just what happened? How's everyone doing? What's next? The family was spread out among other cruisers in the bay.

I've read all these comments, some helpful and some not so much. This is a tragic situation, no matter who or what you might ascribe blame to. Were there mistakes made? Maybe. I wasn't on board and neither were any of you commenting. My only reason for posting is to ask you to consider the family when choosing your words. If you have been offshore yourself, responsible for a boat & crew have you ever made a mistake? Taken a chance? I know I have. I'm a good, responsible, conscientious sailor but I have made mistakes and have been fortunate enough to have not suffered consequences. Just asking for a little compassion.

They don't have any insurance and they could use some help. If you can, please do

https://www.gofundme.comhelprescuethetribe


You missed a forward slash in your link. Here's a working link. I'm glad to see people are helping out.

https://www.gofundme.com/helprescuethetribe
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Old 30-07-2017, 14:33   #109
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

If there is truth to the earlier statement about all sitting down for dinner, makes me wonder who is flying the plane and who is on watch. Since I think of dinner as the evening meal (to some it is not) I also wonder under about the ambient lighting, and the selection of course, no matter what the chart may say. To me, it was to close for comfort, particularly given the "facts" (are they?) I mention. I guess we all make errors, sometimes big, and sometimes good fortune intervenes, and we do not even know how lucky we were.
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Old 30-07-2017, 14:34   #110
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

I know the Southern Pass it is not navigable by night. It is not the easiest by day either. They went for the wrong door. The 'right' pass (one at the town) is miles away. I would be in two minds on whether to take it by night either.

And they were not going for the NW pass as one approaches shallows and shoaling shores at an angle as close to square as possible. So there were quite a number of very basic navigator errors.

Indeed the way Navionics shows the shallow is odd. But it could be configurable. And if it is not, then one is supposed to have something called Chart 1 (INT 1) - a primer that tells you how to interpret the chart at hand.

A leads to B leading to C. And then there is an X at the end of this road.

They are super lucky to be alive and I am happy for them. A boat can be rebuilt or another one had. No lives lost, some lessons maybe learnt. Not too bad at all.

Cheers,
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Old 30-07-2017, 14:34   #111
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

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Originally Posted by Beachcomberz View Post
I have never done an ocean passage or overnight for that matter but in watching a lot of vlogs on YouTube it seems everyone on nightwatch has headphones in for music or even movies. I get that it can't be taxing/boring I couldn't imagine wearing anything. I would want to hear all things around me. Am I wrong?
No, you're absolutely correct. Night watches, even day watches, can be looooong and boring. Most people I know set an egg timer to 5, 10 or 15 minutes to remind them to get up and take a good look around.

It certainly depends on the circumstances - in the middle of a passage, together with radar and AIS, you could stretch to 15 minutes between looks, depending on your speed. But if no radar and no AIS, how many minutes at your passage speed to reach the visible horizon (only 3-5 nm)? For most cruisers, that will be between 30 minutes at 5 knots to 15 minutes at 10 knots. And if a boat coming right at you is moving at your speed, or a ship at 20 knots, how many minutes then?

In squally conditions or storm conditions, or approaching land, what is your risk tolerance? 5 minutes, 15 minutes, 1 minute, between looks? If you're in a danger zone, which being close to land certainly is, what is your alert level?

And if you are on watch, what exactly are you doing even if you are in a position of full visibility? Is your attention outside the boat, or is it on the glowing instruments, or on your hand held device, or inwardly focused as you're blissing out to some music? And with all the light pollution available these days given battery capacities and solar, wind, hydro and generators, how well do you preserve your night vision? Red lights below and night-dimmed instruments? Or just business as usual with white lights below, spilling out and ruining the night vision of the person on watch?
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Old 30-07-2017, 14:43   #112
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by benkay View Post
NAVIONICS:




CMAP:



RASTER:

The Navionics display seems pretty poor, even though the underlying data appears correct. Since these are vector charts how they display is up to the chart plotter software. Using blue as drying reef is not a good UI design. My CMap based charts on a Furuno chartplotter displays drying reefs as an ugly green color. Much more effective.
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Old 30-07-2017, 15:28   #113
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

I would have to say that if the plotter image looks different then it's telling you something is different. Pay attention.
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Old 30-07-2017, 16:28   #114
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

So, looking at the satellite photos, it is clear that they hit the fringing reef, not some outlier. They reported that there were big seas running. When big seas encounter fringe reefs, they generate a LOT of noise, and lots of foam which can be seen even by starlight. If there had been an attentive watchkeeper, the reef should have been spotted by eye and ear in time to take action.

I'm forced to wonder if the lights from the cabin, where dinner was in progress had spoiled the watchkeeper's (if there was one in fact) night vision, and his ears were tuned to conversation and not to listening for reef noise? All conjecture, but more plausible than blaming Navionics charts which appear to be reasonably accurate... certainly accurate enough to tell them they were damn close to the reef and that they should be on high alert.

For those who seem to feel that we should be sympathetic and not critical of their seamanship... well, I am sympathetic, but their seamanship was demonstrably poor, for their boat is stranded and lost. If anyone is to learn from their mishap and avoid the same mistakes in their own sailing, some critique is needed.

Now, a question for those familiar with this boat: where does a watchkeeper normally stand his watch? Some catamarans that i'm familiar with have poor forward visibility from the helm, requiring peering through the cabin windows. This obviously compromises visibility when the cabin is lit and the sea is dark! Some avoid this situation by having a raised seating position where the view forward is above the house... much better, but surely if the cabin is lit, plenty of stray light escapes from those large ports forward and again compromises night vision. So seriously, how do you cat sailors deal with this?

Please don't take this as multihull bashing. It seems a problem to me, and yet most folks who make passages in cats do so successfully; these guys didn't.

Jim
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Old 30-07-2017, 16:47   #115
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by fxykty View Post
Vestas was RACING. All caps for emphasis and not to be obnoxious. When racing, the risk tolerance goes up significantly. That said, the Vestas navigator has admitted that he f**ked up. There were gaps in the reef and he missed. But the competitive advantage in racing of cutting corners has no place in cruising. (Though of course there are some exceptions to that, for example racing a storm into safe harbour.)
Actually the navigator didn't even know the reef was there let alone any 'gaps', but he did take responsibility for the grounding as you say...

The official report is here for anyone that's interested, and I do believe quite a bit of it is relevant to the Cruising fraternity if they are inclined to read it (80 pages ) and I also believe it's no accident that AMSA (Australian Maritime Safety Authority) re-issued Marine Notice 2017/06 on the subject of official charts, seeing as it's the same area...

Link to official report as it's to big for me to post....
http://www.volvooceanrace.com/static...march-2015.pdf

AMSA Notice....
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Old 30-07-2017, 17:11   #116
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Here, for the perusal of interested parties, is a post from Gord May from a few years back, with links for further information about preserving one's dark adaptation:

Re: Colour of Light at Night Vision
Extremely dim light of any colour will preserve night vision (scotopic vision), since that what night vision is for - for seeing in extremely dim light. At these EXTREMELY dim levels, blue-green is the light wavelength we are most sensitive to, and therefore can be used at lower intensity levels than any other extremely dim colour.

Red light preserves night vision, at a higher intensity level than any other colour, since the dim light elements of the eye (rods) are insensitive to red light. This allows you to operate more effectively with red light, as a result of the greater light intensity possible, and therefore more detailed perception of the environment by the red-sensitive elements, of the eye without disrupting your night adaptation.

See also these very important articles:

The Eye and Night Vision
➥ The Eye and Night Vision | American Optometric Association

Night Vision: The Red Myth
➥ Night Vision - The Red Myth

Green or Red for Better Night Vision?
➥ EQUIPPED TO SURVIVE (tm) - Green or Red for Better Night Vision?
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If you want to do your own Google search, try scotopic vision + maintaining.

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Old 30-07-2017, 17:11   #117
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by Jim Cate View Post
...
Now, a question for those familiar with this boat: where does a watchkeeper normally stand his watch? Some catamarans that i'm familiar with have poor forward visibility from the helm, requiring peering through the cabin windows. This obviously compromises visibility when the cabin is lit and the sea is dark! Some avoid this situation by having a raised seating position where the view forward is above the house... much better, but surely if the cabin is lit, plenty of stray light escapes from those large ports forward and again compromises night vision. So seriously, how do you cat sailors deal with this?
...

Jim
Hey Jim,

The Leopard 47 has a raised helm seat on the starboard rear wall of the main cabin and has good all-around visibility (head level when sitting or standing is well above the cabin top and the cockpit bimini and just below the main boom - I sailed on a Moorings 4600 that was a Leopard 47 copy last year in FP). You can see the view from the helm seat in the last blog post showing where all the instruments have been removed. The helm position floor is about 1m above the main cabin and cockpit floor. As the rear wall of the cabin is mostly glass, there is considerable light pollution from inside, especially if regular cabin lights are used. The galley is in the starboard rear corner of the cabin, so essentially immediately below and in front of the helm station. It looks like they had sun shades on the main cabin windows, but those do let light out.

Possibly except for those boats that have flying bridges that are on top of the cabin, light pollution from the main cabin is a serious issue for most cruising catamarans - not only through the rear wall, which has a lot of glass, but through the cabin windows, which will reflect off the deck, sails and deck gear. Another issue with the Leopard and any other design with a stern light mounted on the back of the cockpit bimini is the reflection off the dinghy and other rigging back into the cockpit.

A way to mitigate this is to have red cabin lighting, or at least red zone lighting, for the navigation station and the galley, if galley up. Also don't forget to night-dim the cockpit and nav station instruments, as they produce a lot of white light as well.

Of course, this isn't just a technology issue, as night light discipline in the main cabin and cockpit is very important. I'm sure this is an issue for monohulls as well. And don't forget noise pollution from inside the boat, or the cockpit speakers.

BTW, we have an older Outremer 55L, with helm station on the port side rear wall of the main cabin. Standing at the helm provides 360 degree visibility and we have red cabin lighting as well as red zone lighting. Hull lighting is just white, but I want to add red to the motion-sensitive lights at the base of each set of hull stairs. If the white cabin lights are on, the whole deck lights up and you can't see anything past the lifelines.
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Old 30-07-2017, 17:16   #118
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by Jim Cate View Post

Now, a question for those familiar with this boat: where does a watchkeeper normally stand his watch? Some catamarans that i'm familiar with have poor forward visibility from the helm, requiring peering through the cabin windows. This obviously compromises visibility when the cabin is lit and the sea is dark! Some avoid this situation by having a raised seating position where the view forward is above the house... much better, but surely if the cabin is lit, plenty of stray light escapes from those large ports forward and again compromises night vision. So seriously, how do you cat sailors deal with this?

Please don't take this as multihull bashing. It seems a problem to me, and yet most folks who make passages in cats do so successfully; these guys didn't.

Jim
It looks like from the photo's that it has a semi fly bridge of sorts where the helmsman would be looking over the cabin top...

On another point someone asked if they had radar, it does look from the photo's that a radar dome is mounted on the mast...

For me radars and fringing reefs are made for each other, when properly setup the reef will show up clearly, especially in the conditions stated, you can PI of a fringing reef safely at a prudent distance for as long as necessary, at night through the GBR it's a god send....

Whether the crew on this vessel where using radar I don't know, but it does seem that they had most of the tools onboard to avoid this. That's all I'll say on this other than I'm over the moon that all got out of it well, that I hope lessons have been learned, and that they will be out there again soon...
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Old 30-07-2017, 17:24   #119
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

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Originally Posted by buzzstar View Post
If there is truth to the earlier statement about all sitting down for dinner, makes me wonder who is flying the plane and who is on watch. Since I think of dinner as the evening meal (to some it is not) I also wonder under about the ambient lighting, and the selection of course, no matter what the chart may say. To me, it was to close for comfort, particularly given the "facts" (are they?) I mention. I guess we all make errors, sometimes big, and sometimes good fortune intervenes, and we do not even know how lucky we were.
The first account of this incident on the blog said dinner was being prepared, two kids were in bed, and the father was at the helm.
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Old 30-07-2017, 17:56   #120
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Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

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So, looking at the satellite photos, it is clear that they hit the fringing reef, not some outlier. They reported that there were big seas running. When big seas encounter fringe reefs, they generate a LOT of noise, and lots of foam which can be seen even by starlight. If there had been an attentive watchkeeper, the reef should have been spotted by eye and ear in time to take action.

I'm forced to wonder if the lights from the cabin, where dinner was in progress had spoiled the watchkeeper's (if there was one in fact) night vision, and his ears were tuned to conversation and not to listening for reef noise? All conjecture, but more plausible than blaming Navionics charts which appear to be reasonably accurate... certainly accurate enough to tell them they were damn close to the reef and that they should be on high alert.

For those who seem to feel that we should be sympathetic and not critical of their seamanship... well, I am sympathetic, but their seamanship was demonstrably poor, for their boat is stranded and lost. If anyone is to learn from their mishap and avoid the same mistakes in their own sailing, some critique is needed.

Now, a question for those familiar with this boat: where does a watchkeeper normally stand his watch? Some catamarans that i'm familiar with have poor forward visibility from the helm, requiring peering through the cabin windows. This obviously compromises visibility when the cabin is lit and the sea is dark! Some avoid this situation by having a raised seating position where the view forward is above the house... much better, but surely if the cabin is lit, plenty of stray light escapes from those large ports forward and again compromises night vision. So seriously, how do you cat sailors deal with this?

Please don't take this as multihull bashing. It seems a problem to me, and yet most folks who make passages in cats do so successfully; these guys didn't.

Jim
Good thoughts for us all.
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