Cornish Cruising has incredibly safe boats.

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Divers post-charter

Standard, I believe, in the Whitsundays (the last two, non-Sunsail, boats I chartered were dive-inspected on return). Very little restrictions on who can charter here. It has been a tradition here that Uni of Qld med students hire out just about every boat from Airlie beach after graduation in December - the week starts with an hours sailing lesson (well, I guess they're smart kids). After that, it's on for young and old, as the saying goes down here. Lots of fringing coral round the islands so I can understand the need for dive inspections, most of the students in question wouldn't remember if they smashed into something. Might all change now that breathalysing on the water is an intrusive reality.

Pretty impressive to manage a passage from the Scillies sans keel - sounds like the sort of exercise they would make you try at Glenans sailing school if they taught keelboat sailing.
 
You would think so wouldn't you, but I looked at that at the time and couldn't see anything untoward. When I had my Jeanneau 42 the difference in waterline from when she was brand new and empty to when she was full of all sorts of stuff was not discernible. I guess its a feature of these modern falt bottomed designs.

Still can't get my mind around why she stayed upright, I would love a naval architect or stability expert to tell us - anyone out there?

Not a NA but my two pen'orth:

According to brochure specs here: www.jeanneau.fr/inventaire/brochure_20080229_90_.pdf

Ballast ratio is 30% (Polbream is the deep keel version) which is relatively low. A Contessa 32 (everyone's favourite comparison!) is 47% so if you lost your keel in a CO32 you'd ride comparatively higher.

Modern boxy, beamy hulls have a higher Block Coefficient (ratio of actual displacement to disp of a box size of Lwl x Bwl x hull depth) and so rise and sink less when weight is added or taken away. This factor is known as sinkage or immersion (measured in Pounds per Inch Immersion)

SO37 has a beam to length ratio of just under 3. Increased beam leads to increased stiffness intially (steeper/higher intial curve on GZ chart) but less self-righting ability and a lower angle of vanishing stability.Also in an older CO32 type with slacker bilges it would immediately feel more tender and possibly want to sit over on it's side. On a modern high volume hull the effect would be less noticeable. I would imagine the beam waterline would not be reduced as much by riding higher.

The indication was there though in it's 'skaty' handling and increased turn radius.

I would guess that even though 'knocked down' she just didn't reach her (keel-less) AVS and came up as a result of form stability alone. In beamy flat bottomed boats there is an enormous outward shift of the centre of buoyancy as the boat heels. Even a dinghy will come back up from 70-80 degrees if not flooded.

A boat like the SO37 (in normal operation) is relying much more on form stability and much less on ballast than the CO32 type. Hence it's less devastating when the ballast exits stage right!
 
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Adding the cost of an underwater inspection to check the keel is still there after every charter? Who's smoking funny stuff?

At what point in time do you institute a regime in a companies systems?

This is not the first time that this operator has had a problem with substantial damage to keels on their boats.....

A few years ago I watched one of their boats park itself onto the bar at the bottom of the Fal... according to the reports afterwards the charterer didnt report it... but the damage ran into 10's of thousands... and if the boat had gone out afterwards???.

The fact is that they sent out a boat which had a potentially very real fatal flaw.

Think about the downside of this from the companies perspective.

A video inspection would probably take 10 or 15 minutes and cost virtually nothing.

No brainer I think.

If the charterer knows that he is gonna have a inspection 2 things might happen;

1) they will be forthcoming when having a accident... thereby reducing risk of further problems..
2) They may be more carefull with the boat... thereby reducing damages..

Both of these will drive down costs... so it may in the end have no negative impact on costs.



Of course it is easy for some who dont have a keel to think that it may not be important to have one!:D

I see were your coming from though... the idea seems ridiculous...
 
Maybe manufacturers (or an after market solution) could bond a strain gauge into the keel with a 'black box' for owners/charter companies to look at the historical plot of stress and strain... up to a red flashing light if said strain gauge disappears altogether :eek:
 
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Every charter vessel in the UK is coded. You have to report a grounding to the MCA and/or their agents. They then ask for a haulout and inspection. <snip>

That seems a bit draconian ... however, I don't think it onerous for a charter company to visually inspect keel, prop & rudder - either by diver or by camera - whichever easier - especially if a grounding has been reported. I can only assume that neither a haulout (as indicated by TiggerToo would be required), nor visual inspection carried out - although perhaps they did inspect the keelbolts?..

I don't like knee-jerk legislation - especially the "it must never happen again" sort - as it usually results in loads of arse covering, expense and very little benefit. Then again - I would expect a charter boat to be with all the kit in place .... including a keel!
 
I dont think we need legislation... we just need companies who charter yachts to properly appraise the risks..... I think that a customer should not have to bear responsibility for the intrinsic safety of the boat... and clearly a underwater inspection is something that is reasonable to ensure that the boat is fit for purpose.
 
That seems a bit draconian ...

I don't think we are talking legislation here. I am not sure what the exact nature of the legal position of the MCA is re coding: are there any MCA-accredited surveyors who would like to comment? But it seems to me logical that if a boat takes a knock which may result in damage and strain that is beyond the normal use, a survey would be recommended. We are talking about charter boats for which we have a duty of care.

It is not about "nanny statism", it is about standards for what is a commercial operation. What you do with your own boat for your own use is up to you (and whoever may decide to come on board with you).

Anyhow, the video camera suggestions aired here seem sensible to me, and I will see if I can get it implemented for Tigger (I need to discuss it with the guys who manage her). It is not a++e covering, just a sensible thing to do. Both as an owner and as a user I'd like to know if the underwater hull had taken some untoward knocks.
 
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You would think so wouldn't you, but I looked at that at the time and couldn't see anything untoward. When I had my Jeanneau 42 the difference in waterline from when she was brand new and empty to when she was full of all sorts of stuff was not discernible. I guess its a feature of these modern falt bottomed designs.

A quick google gives LOL 11.4m, beam 3.7m. Knocking that down to 10m x 3m to allow for overhangs gives a block area of 30 m^2, of which probably 70% or so, 20 m^2 will be filled by boat. That means a draft change of around 5 cm per tonnes, so 1.7 tonnes of missing keel would let her float somewhere (all this is very ballpark) between 5cm and 10cm higher. I would have thought that would be around the noticeable mark if you were familiar with the boat, probably not if you weren't.
 
A quick google gives LOL 11.4m, beam 3.7m. Knocking that down to 10m x 3m to allow for overhangs gives a block area of 30 m^2, of which probably 70% or so, 20 m^2 will be filled by boat. That means a draft change of around 5 cm per tonnes, so 1.7 tonnes of missing keel would let her float somewhere (all this is very ballpark) between 5cm and 10cm higher. I would have thought that would be around the noticeable mark if you were familiar with the boat, probably not if you weren't.

Yeah I got more or less the same:

Lwl 9.7m x Bwl 3.33m (Bwl not published but assuming 90% Boa)
= 32.3m sq

Assuming a waterplane coefficient of 0.72
(at the fat end of a typical: 0.67-0.72)

Waterplane area: 23.3 m sq
Immersion: 233kg/cm

or
7.3 cm for 1700kg
(or slightly more as you are removing weight and the cm below the waterline displaces less)

Not very much on a 37 footer! :eek:
 
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1. Truly stunned that it stayed up right
2. More amazed that there was no water ingress
3. Puzzled that handling characteristics were not noticed but equally very easy to claim it should have been obvious after the event, sometimes the obvious staring you in the face isn't noticeable until it is pointed out. Haven't we all had those Doh moments!!!
4. In fairness before this story I think the last thing anyone would ever dream of is that a yacht can sail around without a keel. It is pretty much unprecedented. That said i would expect to see some signs elsewhere around the boat that there was a problem.
5. Agree that there is an onus of responsibility on the charter company to check after a reported grounding even to the extent of lifting a boat. But if no one reports an incident and after a visual inspection of the bilge area as a routine in between charters then i think OTT for charter company to be expected to dive on each boat in between charters. After all it would be reasonable to expect some noticeable and visual sign as an indication that there might be a problem.
6. Continuing my point about visual signs, i would expect to see something, cracks around inner moulding, shifting bulkheads / furniture, so instead of investing in under water camera's i would train staff better so that they are on the look out for tell tail signs of groundings / missing keels.
7. Like any risk assessment Charter companies set policies depending on level of risk. If you charter amongst coral reefs where there is a high risk of damage, i guess these guys have worked out that the additional cost of diving on the boat is commercially worth it given previous incidents and as they have probably got bored picking up the repair bill when the yacht is hauled out. Where there is a low risk or no conceivable risk then it is hard to argue that a charter company should be diving on a boat between charters. Again if you ask the charter company what they are looking for when they dive on a boat i doubt anyone would say they are checking to see if the keel was still there and more that they are looking for small signs of damage to the rudder & keel appendages as well as ropes around prop's etc so they can offset their repair costs at the end of the season.
8. Easy to manage diving on boats overseas in warm water and where there is no Health & Safety. Diving in a UK marina is a costly expense which would be hard to add to the charter fee unless everyone does it. Also to make it stand up legally i suspect that you would have to carryout the inspection in the presence of the charterer both before and after their charter.
9. Not sure that a make shift camera would pick up signs of a grounding or that the keel is about to fall off in the murky waters of the South Coast, yes it would pick up a missing keel but I come back to my point about realistically prior to this incident would anyone imagine that a yacht would stay upright without a keel let alone sail around. You would expect to see some other sign for such a catastrophic incident.
10. Normally these failures (where there is no design / manufacturing failure) manifest themselves over a period of time and are caused by repeated groundings and the fatigue that this causes. I would suspect that this is not the first time the boat has run aground.

Some good lessons to be learnt from this incident but as always a balanced perspective has to prevail.
 
...or
7.3 cm for 1700kg
(or slightly more as we are removing weight and the cm below the waterline displaces less)

Not very much on a 37 footer! :eek:

Surely you'd notice if the boat is 6" higher in the water. Maybe not a charterer unfamilar with the boat but surely someone from the charter company would remember not painting anti-foul that far up the side. Unless the boat had been scrubbed recently the normal waterline scum should've been obvious.
 
So if the waterline changes by 7 cm vertically then as the hull at the stern rises out of the water very gradually on such a boat then the point the water reaches to at the stern must change considerably more if measured along the hull. If I guess 20 degrees for the angle at which the hull is inclined to the water at the stern then I make it about 20cm difference?? So to someone who knew the boat well it might have been very obvious if you looked there.
 
Maybe manufacturers (or an after market solution) could bond a strain gauge into the keel with a 'black box' for owners/charter companies to look at the historical plot of stress and strain... up to a red flashing light if said strain gauge disappears altogether :eek:

It's not unknown to have a load cell at the forestay on racers, mainly for the benefit of whoever is cranking on the runners.

I guess you could put one on the keel with a little "keel still present" light at the chart table. In fact you could design a circuit with one of those fancy LEDs that change colour from green to red as the keel falls off.

The deluxe model could be connected to the DSC VHF to send a KoB alarm to the coastguard automatically. :-D
 
Just to add my perspective to the 'dangerous charter boat' thing.
I did my DS on a boat that when it was hired to us, had a forstay hanging on by a few strands. Had this not been spoted by out skiper, it could have led to catastrophic rig failure. Yes of course charter companies should have high standards of maintanence and inpection, but they can't mitigate against every posible failure. Sailing is said to be safer that the drive to the marina, but surly everone who takes to the water apreciates there is still some risk, its life!
 
It's not unknown to have a load cell at the forestay on racers, mainly for the benefit of whoever is cranking on the runners.

I guess you could put one on the keel with a little "keel still present" light at the chart table. In fact you could design a circuit with one of those fancy LEDs that change colour from green to red as the keel falls off.

The deluxe model could be connected to the DSC VHF to send a KoB alarm to the coastguard automatically. :-D

ha!

(or of course you could simply drill a hole in the keel and attach it say to the boarding ladder... the splintering fibreglass as it was ripped out would surely attract someones attention...)
 
and clearly a underwater inspection is something that is reasonable to ensure that the boat is fit for purpose.

Oh what utter nonsense. I'm not sure how many individual charters happen every year nor how many keels fall off like this, but am fairly certain I am safe in saying that it is in the many thousands to one category.

Are you seriously suggesting all charter companies should change how they operate and instigate underwater inspection upon return of the boat?

Seriously?

Really?

Have you got shares in a diving company or underwater camera manufacturer? Or have you been brainwashed by the elf & safety brigade?:D:D:D:D

What sort of nanny state do you want? Perhaps we should all have our car tyres x-rayed (after we go over a pot-hole or road lump) for stress damage just in case they blow-out.

Or perhaps every shackle on a boat should be tested after every sail just in case it has been unduly loaded and damaged.

Oh please.....

OK I've bookmarked this thread so I can link to it from the next 'nanny state' thread.

I'm with you on that.
 
So if the waterline changes by 7 cm vertically then as the hull at the stern rises out of the water very gradually on such a boat then the point the water reaches to at the stern must change considerably more if measured along the hull. If I guess 20 degrees for the angle at which the hull is inclined to the water at the stern then I make it about 20cm difference?? So to someone who knew the boat well it might have been very obvious if you looked there.

I see what you mean but the 7.3cm (3" not 6" by the way) is an average value.

(Which I worked out roughly based on several assumptions! To get it accurately you would need more info: specifically the waterplane area and beam waterline)

It depends where the centre of gravity shifted to, following the loss of the keel. If it shifted aft (in other words the keels cg was forward of hull cg) then the boat would trim by the stern anyway and not be so noticeable there.

If it was only 7cm or so then we are talking less than 1% of the waterline length which I imagine would be difficult to spot.
 
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If it was only 7cm or so then we are talking less than 1% of the waterline length which I imagine would be difficult to spot.

Especially if the water wasn't dead smooth. And more especially when the boat's tucked into a finger berth among lots of others, so you don't get a clear side-on view from a reasonable distance. And even more especially, as for much else in this case, when a missing keel is not a possibility you would ever contemplate.

Pete
 
3. Puzzled that handling characteristics were not noticed

If you read the post in this thread from one of the crew, you'll see that it was noticed. They remarked on how poor the handling was, and as a result of it the experienced skipper had a minor prang with another boat. They wondered whether perhaps they had a net round the keel.

Not surprisingly, they didn't consider the possibility that there was no keel at all.

Pete
 
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