Team Vestas hits reef

[Tangogirl]

This may have been already posted, but in case not:


Watch Nightmare Unfold Onboard Team Vestas While Hitting Reef at 19 Knots - gCaptain Maritime & Offshore News

[cagney]

Originally Posted by colemj

I think you have made assumptions and used them as a baseline fact. Here is the CMAP vector chart of that region zoomed out to show the whole world.

The reef they hit is clearly visible (I marked it with a small red X), and remains visible at all zoom levels. This has nothing to do with raster/vector/paper/electronic.

I posted this earlier in the thread.

Mark

You are wrong. The only info you get out of CM93 is that the "blue" area has depth between 0 and 200 m. There is no info whether there is a reef dangerous for navigation or not, at the zoom levels you are referring to.You are reading info into CM93 that's not there. Please do an "object query".

Thomas

[El Pinguino]

Oh Dear,
You give the maritime world a more foolproof system and sure enough they will give you a better class of fool.
Nothing new or remarkable about all this. Try this for starters MS Oliva Safety Report Findings , the official Maltese report is out there somewhere but suffice to say this was a result of 'under zooming'.
Closer to home someone I was aquainted with (master class 1, etc etc etc) did mega millions of damage to a nice new ship by 'overzooming'...as the AMSA surveyor said( paraphrasing here) ... 'you would have thought that the title of the paper chart hereabouts being 'Rocky Cape to Stoney Head' would have been a bit of a giveaway'

Anyway... using my CM-93 charts ,which are - by the way- industrial grade, together with both OpenCPN and my 'BurgleBrand' Cmap software I found the following.

Yes... you can see the Cargados Carajas Shoals from outer space... but just as a bank less than 200 metres ( the 100 fathom line in Noah's day) with no detail at all... you have to zoom in some considerable way before you get any useful detail and you end up on a scale of little use when shuffling along at 19 knots. Pics are of OpenCPN ...

[El Pinguino]

These are the results using my original 'Burglebrand' C-Map software which was given to me by that nice Mr Ivan Ivanovich who used to work for C-map in St Petersburg

[Muckle Flugga]

Originally Posted by clownfishsydney

There was a lot of video on the TV News tonight in Sydney on this. It showed the video of them running aground and also the crew salvaging items from the wreck.

It was also claimed that they are going to salvage the boat, repair it and sail the next leg of the race. I think this is very, very optimistic. I doubt that they would even be able to salvage the boat off the reef given how remote it is, let alone repair it enough to continue racing.

Also someone mentioned that radar should have shown the reef. No way, the reef and island are so low there is very little chance that they would have sent back a reflection.

I fully agree that it is very unlikely that any effective salvage will be made of the hull, in time for continuing the race. Really, I doubt that any restorative salvage could be made at all.

However your assertion about radar imaging low lying reefs and islands simply isn't true. Perhaps you are basing this on experience of radars sets many years ago? However I can tell you without any doubt whatsoever that atoll reef lines, including those just above the waterline at low tide are fully visible on a modern radar set. I am currently at Port Dixon, near the upper end of the Malacca strait, and enjoying a fever. Anyhow, 36 hours ago, while traversing the lower end of the straits in a total flat calm, I noted that my now 7 year old Raymarine set was perfectly capable of forming very good radar targets from lumps of wood and weed floating just above the surface, around 2-6 meters in length and less than 50cm high. I have negotiated MANY poorly charted atoll entrances using radar assistance, to assist position correctness, and navigated among many atoll groups (with zero islands above a motu height) using radar as the main tool of avoidance. About the capacity to see this structure, if not FULLY submerged to the point that there were not even breakers (don't forget that waves do indeed appear as radar targets so even permanently submerges structures which simply cause breakers are visible), are just, simply, quite flat out wrong.

[El Pinguino]

Originally Posted by Muckle Flugga

Anyhow, 36 hours ago, while traversing the lower end of the straits in a total flat calm, I noted that my now 7 year old Raymarine set was perfectly capable of forming very good radar targets from lumps of wood and weed floating just above the surface, around 2-6 meters in length and less than 50cm high.....

Depends I guess.... using 25kW radars and 'target tails' or whatever the afterglow thingos are called these days we could see the evening migration of seagulls back to their camp on Mud Island...
But get a heavy sea and swell outside PPH and you could lose 5,000 ton ships at four mile range in the sea clutter....

Tricky stuff .. radar

[Muckle Flugga]

Originally Posted by jtsailjt

I wasn't referring to your posts.

In response to another persons post, I did point out that multiple GPS's are less likely to become useless than a sextant since all it takes for a sextant to become useless is a cloudy day, which are pretty common at sea. In other words, the assumption that some seem to have that the "tried and true" sextant is the ultimate reliable means of navigating doesn't really hold much water. I didn't even attempt to address the reliability of paper charts vs the human error that is possible when that chart is transformed into a digital format. Certainly that conversion introduces a possible source of error and I wouldn't argue against using a paper chart with a GPS or multiple GPS's, especially in remote areas where you aren't sure that your chartplotter'(s) database is/are entirely accurate. But in this case we are discussing, in the middle of the Indian Ocean, it wasn't a database problem OR a lack of paper charts that caused the grounding. Even IF they were primarily using paper charts, if they were going to carry enough paper charts to show every little island in a large enough scale to use that chart to navigate close to them, round the world racers would be carrying so many charts that are almost nothing but blue with a lat/long grid on it that they'd have trouble finding room to stow them all aboard a racing sailboat and in this case, if it was too much trouble to look at their chartplotters, I think it's safe to say it's unlikely that they'd always have the correct chart out with someone dutifully plotting their position all the way across the Indian Ocean.

But if you are frequently sailing in areas where you don't trust your chartplotters database, I agree that it's a great idea to hold onto your paper charts and use them in conjunction with your GPS(s) and other electronic aids, but if we're talking about counting on using a sextant for backup navigation, I think you'd be much better off to simply buy another portable GPS and a box of batteries for it that you keep in a sealed, waterproof container.

Sorry, I should have realised you were not referring to my posts. I always carry a sextant and do use them from time to time but admittedly rarely. I more often use instrument less navigation as a hobby to pass the time in the many long night watches in remote areas. But yes, GPS is the main reliable method of modern navigation. One thing, though: you are rather wrong about your statements concerning paper. Even on the General Chart of the Indian Ocean these shoals and reefs would appear. One of the great advantages of paper over plotter, still, is that the vast majority of major hazards are ALWAYS charted on paper. They are often not to scale, but correct in location precisely so that they appear. If the navigator had had been plotting onto or simply glancing over a general chart of the area in question (and don't forget that only a handful of such charts are necessary for each leg, and you can fit around 25 charts in a 3" diameter tube) he would inevitably have seen that they were TO BE passing directly through the area of these shoals. Paper is definitely useful for this reason, and has often saved my ass from making stupid errors like this, despite the fact that I ALWAYS "fly through" on my chart plotters. Some have better interfaces than others for this (for example I really like the Nobeltec plotter, as it can take Vector and Raster charts and holds much greater detail at higher zooms in a more legible format than the Raymarine sets do, for example). Paper just is a one stop shop for giving advance warning of particular and general hazards across immense areas at a glance, and will continue to be until plotters start being built with A2 and above format screens.

[El Pinguino]

Originally Posted by Muckle Flugga

Paper just is a one stop shop for giving advance warning of particular and general hazards across immense areas at a glance, and will continue to be until plotters start being built with A2 and above format screens.

Yup, what he said x 100!

[poiu]

Originally Posted by El Pinguino

These are the results using my original 'Burglebrand' C-Map software which was given to me by that nice Mr Ivan Ivanovich who used to work for C-map in St Petersburg

I can see them on my CM-93 2010 charts, but not on the 2011 edition. I don't have the versions you show.

It is clear though on the 2011 chart that there is no detail available by the absence of a red line outline indicating the chart's area, so if should be up to you to then do something about the lack of charts, like get one or go somewhere else.

[Muckle Flugga]

Originally Posted by El Pinguino

Depends I guess.... using 25kW radars and 'target tails' or whatever the afterglow thingos are called these days we could see the evening migration of seagulls back to their camp on Mud Island...
But get a heavy sea and swell outside PPH and you could lose 5,000 ton ships at four mile range in the sea clutter....

Tricky stuff .. radar

Quite true. It is tricky. And definitely not foolproof. I have found, however, that usually you can see a long breaking reef line like this in any but truly violent conditions. And the VOR racer had a gimballed transmitter. Whatever the sea state, it is going to be a LOT bigger as it intersects the reef line, and the reefline in this case was more than 30 nautical miles in length. That structure should have shown up on any set in any but the most violent conditions. So you're Kiwi? Where abouts? Was in Opua and Whangerei earlier in the year.

[Suijin]

Originally Posted by Muckle Flugga

Quite true. It is tricky. And definitely not foolproof. I have found, however, that usually you can see a long breaking reef line like this in any but truly violent conditions. And the VOR racer had a gimballed transmitter. Whatever the sea state, it is going to be a LOT bigger as it intersects the reef line, and the reefline in this case was more than 30 nautical miles in length. That structure should have shown up on any set in any but the most violent conditions. So you're Kiwi? Where abouts? Was in Opua and Whangerei earlier in the year.

Will Oxley on Alvimedica estimated that at the time of the grounding that the sea was more than 1.5 m above the top of the reef. It was relatively calm conditions, blowing about 15k. None of the VOR skipper/navigators that have commented on rounding the reef have made any mention of radar as an effective means of confirming position so I suspect that it has not proved useful in the conditions they encountered.

[El Pinguino]

Originally Posted by Muckle Flugga

So you're Kiwi? Where abouts? Was in Opua and Whangerei earlier in the year.

Nope, not kiwi, I'm Strayan. Boat is just in Unzud for major refit.... hope to be on my way back to Chile in early 2016.

Re not seeing the break on the reef... If a big sea is running then the flat water beyond the break should show up well... or not show up... depending on how you look at it...
Cheers,
El Ping

[downunder]

Originally Posted by clownfishsydney

There was a lot of video on the TV News tonight in Sydney on this. It showed the video of them running aground and also the crew salvaging items from the wreck.

It was also claimed that they are going to salvage the boat, repair it and sail the next leg of the race. I think this is very, very optimistic. I doubt that they would even be able to salvage the boat off the reef given how remote it is, let alone repair it enough to continue racing.

Also someone mentioned that radar should have shown the reef. No way, the reef and island are so low there is very little chance that they would have sent back a reflection.

Properly tuned radar will show reef breaks and swell well enough for nightime navigation to give safe clearance distances. Particually the latest systems.

[Muckle Flugga]

Originally Posted by El Pinguino

Nope, not kiwi, I'm Strayan. Boat is just in Unzud for major refit.... hope to be on my way back to Chile in early 2016.

Re not seeing the break on the reef... If a big sea is running then the flat water beyond the break should show up well... or not show up... depending on how you look at it...
Cheers,
El Ping

Back to Chile? You don't, by any chance, have a red hulled boat do you? Ah, I see not, from your links. I thought, for a moment, that I might know you. I look forward to sailing the fjords sometime. Are you heading "back" via the Australs and Gambiers? Steel boat?

[donradcliffe]

Originally Posted by Jim Cate

Interesting! I have 2006,2010 and 2011 updates. They all show big shallow areas when zoomed out, but no detail. But when zooming in, the 2006 and 2010 show great detail of the whole reef and island complex. As you say, the 2011 version has cropped off most of the detail. This is one of the problems with these charts: as one goes between versions, detail areas come and go. We've seen this in the Vanuatu area in particular... can be disconcerting and drive one back to looking at the older paper charts that we carry.

Jim

I've also seen CM93 charts come and go with updates, which is very disconcerting. If you hit the properties of each CM93 update, you will see that they don't have the same number of files--some of the older versions have a lot more files. I was always tempted to take the latest edition and copy the older additions onto it using the "don't replace duplicates" to make sure I hadn't lost any charts in their 'update'.

As you will hear from all the experienced navigators here, its not a question of paper vs electronic or raster vs vector--a good navigator takes ALL of the available tools into account, and makes sure that they are singing in tune. Any discrepancies (between charts, between eyeball/radar/depthsounder/ears/waves/smells/etc and charts) and its time to go on alert and steer clear or stop the boat if necessary until they are resolved.

From the Vestas video, I think they were on port tack with the wind blowing off the reef. That would have made it less likely to see the reef on radar, but the radar would have picked up some targets, as they were within a mile or two of an island with houses. It would have made it more likely that a good seaman would have smelled the reef. The sea state should have also changed as they got in the lee of the reef.

As for whether the reef showed up on the charts, the darker blue on the small scale CM93 chart is an alert to the navigator that there may be dangers and its time to look further.