Independence | Upadates & Cruising

[Hardmy]

LR, you did an impressive trip! You were also wise enough, to put together a capable crew. The navy guys had experience of sailing in poor weather, but on boats built for this purpose. So its reassuring that a pleasure craft like your Trader survived unscathed such hard treatment.

What amazes me the most is that she recovered apparently effortlessly from heeling up to 38° so there was still a reserve of righting moment! Sorry if its a bit OT, but did you try to ask Trader (or the builder Kha Shing) to get the stability curve of your boat? And how did you measure your heeling so accurately?

 

[londonrascal]

38° was a good estimate not a conclusive amount of list experienced. However, since the boats operating manual states its maximum list before water can enter the hull (through the engine room air intake baffles on side of the hull) is 36° and since we had water coming in from these when listing over heavily, it therefore was obvious the degree of list had to be 36° minimum.

The engine room generally - ladder, engines and surfaces had a lot of dried salt spray over along with salt water pooled in various areas where there is no path for it to drain into the central bilge area. This took some cleaning up last weekend when I was down on the boat.

Generally speaking I am sure if the RIB was not up top along with the Crane she would have heeled over far less - that said, we tried to ensure that on each leg we had brimmed fuel and water tanks to give as much low down weight as possible to counter the upper weight, which I estimate to be between 600kg and 700kg taking into account the weight of the RIB and crane.

 

[nicho]

Most will land and take off again 6ft and land again under auto-rotation. I won't go into the plane v helo thing lol :encouragement:

You beat me to it. Autorotation is a non event.

 

[Greg2]

Reading the recent posts following Robins video clip I am curious about the stability of Independence.

Griff said ‘At least we have proved one thing after the delivery weekend afloat. Traders can survive in heavy seas, with a large crane / rib mounted topsides WITHOUT stabs fitted.’

Robin says that the boat can heel 36 degrees before it will take on water through the engine bay air intakes and that it was beyond that at some points as there was water ingress into the engine bay.

Now I don’t know what is required when leisure boats are assessed for CE marking but for commercial coding a stability test and book is required that will account for any load that may be carried on deck, any lifting gear and the height it can hold weight above the waterline. I know from experience that it is not acceptable for theoretical heel to reach the point where water ingress could occur through engine bay vents. Even though they have baffles the danger presented by water ingress and the rapid effect that it can have on a vessels stability means that there is little of no tolerance.

Leaving aside the issue around Stabs, because I think they would be irrelevant when it comes to passing a stability test on the basis that they can be non-operational, I am wondering whether or not Independence would pass a stability test and how safe was she in the conditions described. Is the boat very capable and able to deal with the conditions experienced during the trip or was there a theoretical risk at least that she could have foundered?

You only have to read the MAIB bulletins to see what can happen to apparently well found vessels in the wrong circumstances / conditions.

Mentioned in the spirit of theoretical musing only and not intended to be critical

 

[Portofino]

You may be barking up the wrong tree .
Any list or excessive say 30 odd degree could be because it’s on the side of a wave / swell in a beam sea .
It does not need to tip from a flat marina mill pond to record 30 odd degrees inside the boat .

Any salt deposits / water in the ER via the intakes baffles could be ingested spray settling as opposed to water running in because the orraface was breached .
Also there’s was a constant source of sea spray from water running down from above draining off the superstructure.

I have my doubts if I understand your Q correctly? , that the sea water level actually breached the orrifaces

 

[superheat6k]

Reading the recent posts following Robins video clip I am curious about the stability of Independence.

Griff said ‘At least we have proved one thing after the delivery weekend afloat. Traders can survive in heavy seas, with a large crane / rib mounted topsides WITHOUT stabs fitted.’

Robin says that the boat can heel 36 degrees before it will take on water through the engine bay air intakes and that it was beyond that at some points as there was water ingress into the engine bay.

Now I don’t know I what is required when leisure boats are assessed for CE marking but for commercial coding a stability test and book is required that will account for any load that may be carried on deck, any lifting gear and the height it can hold weight above the waterline. I know from experience that it is not acceptable for theoretical heel to reach the point where water ingress could occur through engine bay vents. Even though they have baffles the danger presented by water ingress and the rapid effect that it can have on a vessels stability means that there is little of no tolerance.

Leaving aside the issue around Stabs, because I think they would be irrelevant when it comes to passing a stability test on the basis that they can be non-operational, I am wondering whether or not Independence would pass a stability test and how safe was she in the conditions described. Is the boat very capable and able to deal with the conditions experienced during the trip or was there a theoretical risk at least that she could have foundered?

You only have to read the MAIB bulletins to see what can happen to apparently well found vessels in the wrong circumstances / conditions.

Mentioned in the spirit of theoretical musing only and not intended to be critical

Interesting comment - do the designers allow for the top weight of a rib and derrick, especially when the tanks run low, after all pleasure boats do not generally pay attention to any necessity to carry ballast weight. If the designer has not factored in adding said Rib and derrick does anyone pay any attention to the affect on the lifting of the CoG, and with it reducing the metacentric height and consequent stability ?

 

[Greg2]

Portofino - Well I am basing it on what has been said so I don’t know for sure whether or not the boat did actually heel beyond 36 degrees. Robin said it did and that water was coming in through the vents when it happened - perhaps an (understandable) inaccurate perception of what was actually happening on his part. Who knows. Might be barking up the wrong tree but it just got me thinking.

Actually, I guess leaving aside what actually did or didn’t happen there is still the question about whether or not Independence would pass a stability test - one would hope that the manufactures calculations took account of the crane/Rib set up........

 

[Greg2]

Interesting comment - do the designers allow for the top weight of a rib and derrick, especially when the tanks run low, after all pleasure boats do not generally pay attention to any necessity to carry ballast weight. If the designer has not factored in adding said Rib and derrick does anyone pay any attention to the affect on the lifting of the CoG, and with it reducing the metacentric height and consequent stability ?

Yep, that is precisely what I am wondering

 

[londonrascal]

Well without the tools on board to be able to prove the points, all we know is when I was onboard coming round Portland Bill and we took a rouge wave on our starboard side she sure heeled way over and water did come in through the port side air intake in the hull as she heeled over to port. I was then told by Charlie between Dover and Great Yarmouth that this level of heeling over was a common occurrence as they had an enormous swell and waves on their starboard beam. I was also told they were often looking out of the wheelhouse windows on the starboard side and seeing just water - having to bend down and look up to see the top of the waves which were often some way above the top of the boat.

The fact that was going on hour after hour with the boat being pushed right over on her port side says a lot for the design of the boat despite the additional weight up top and by then far more depleted wing fuel tanks (as they had not been topped up since leaving Brighton) so there was less low down weight.

Anyway just really popped on to share this little clip taken by follows of our trip who had tracked us when we cruised passed Dungeness.

 

[NBs]

LR, you did an impressive trip! You were also wise enough, to put together a capable crew. The navy guys had experience of sailing in poor weather, but on boats built for this purpose. So its reassuring that a pleasure craft like your Trader survived unscathed such hard treatment.

Hi,

the original GZ curve is not beneficial in practice because it is just a theoretical calculation that does not take into account the realities of real life. Different shapes of wave, wind, gust, your accessories load vs standard boat.

NBs
What amazes me the most is that she recovered apparently effortlessly from heeling up to 38° so there was still a reserve of righting moment! Sorry if its a bit OT, but did you try to ask Trader (or the builder Kha Shing) to get the stability curve of your boat? And how did you measure your heeling so accurately?

 

[NBs]

You may be barking up the wrong tree .
Any list or excessive say 30 odd degree could be because it’s on the side of a wave / swell in a beam sea .
It does not need to tip from a flat marina mill pond to record 30 odd degrees inside the boat .

Any salt deposits / water in the ER via the intakes baffles could be ingested spray settling as opposed to water running in because the orraface was breached .
Also there’s was a constant source of sea spray from water running down from above draining off the superstructure.

I have my doubts if I understand your Q correctly? , that the sea water level actually breached the orrifaces

Hi,

And, in addition, the engines absorb a huge amount of air through the demister, from which some water gets in, because the waves hit the side and it rises up as a liquid or spray.

The boat does not necessarily have to be tilted in order to get water into the machine room. Do you have an angular ° meter if you do not get an phone application that measures the angles ° and you know the fact how close you are to the risk angle you are.
And you can change the driving direction better than tilting less.

If the average wave was 2-2.5m in the video it should not yet pose any risk of traveling with a Trader boat or causing a 30 ° tilt to close, whether I am wrong, but would this boat be CE-A category?

NBs

 

[Greg2]

I get that water/mist will find its way into the engine bay in rough conditions and that is, perhaps, the more likely explanation for water/salt deposits being found down there after the passage.

Robin says that water was coming in the port engine vents when the boat heeled to port in big seas that were coming from the stbd beam. I am wondering how he knew this - webcam in the engine bay? I am not familiar with the design of the Trader but on our Broom 41 the vents were high in the hull, but below the saloon deck so the only way we would have known that there was water ingress would have been to physically check the engine bay.

The conditions in the video don’t look too bad (although cameras never convey true sea conditions) and the boat looks to be riding well. I am sure that it looked and felt bit different for those onboard though

 

[petem]

Water ingress should also trigger the bilge alarms. I assume the bilge pumps were running to pump out the water that was coming in?

 

[Portofino]

Water ingress should also trigger the bilge alarms. I assume the bilge pumps were running to pump out the water that was coming in?

I think that’s a given P
Ideally you want one @ each end to capture the water as it sloshes about .

 

[londonrascal]

Another longer video has just emerged on You Tube of the trip - remember this video is off of Dungeness and this was not where the boat was in any beam sea, heeling over or anything else - just bang on the nose so the video is not evidence of what we have been talking about (degree of list) just an indication of the conditions to begin as we passed the headland.

Conditions got steadily worse as we carried on to Dover and night fell. The following day (when I was not personally onboard), they got significantly worse and, as I stated before the top of waves regularly being over the height of the boat with crew inside needing to stoop down, looking 'up' out of the side windows just to see where the top of the wave were. During these seas, crew who were sat down would find themselves in a 'seated standing' position - they were able to look down at the sea, not up to the sky form their seat which normally you'd never be able to do since the seating is pretty low down in the saloon.

One would be aware water was entering the boat during such moments because the bilges would suddenly have several inches of water sloshing about in them - having poured in from your hull air intakes. The reason one was aware of this is because of the regular engine room checks on the engines and equipment that we undertaken when underway and which included checking bilges, pump operation and so on.

Another interesting point is when the sea state is rough enough to send a bunch of water from one end of the boat to the other, hit a bilge pump float switch with such force that it caused it to stick in the open (up) position so the pump would run continuously - so keeping an eye on the bilge pump LED indicators as to how often they were running and for how long also became 'a thing' - every so often when a pump would not go off inspection would need to be made by lifting up the hatches get down and inspect was it a flooding incident or a float switch once again stuck in the up position. During one of these inspections Charlie 'took off' from the cabin sole and hit his head on the secured steps above him which normally you'd never be able to achieve because there is a large clearance between the two, but in those sort of seas it was not an easy task to stay down or in one place.

Of course she is not going to likely see such conditions again but to have been through such and come out the other side without damage or issue (other than a midships cleat on starboard side now being a bit loose, auto-helm no longer functional, a possible hydraulic leak from the take off pump for the thrusters and a fuel vent pipe chaffing) I think is pretty impressive - the forces generated were pretty extreme and not what you would want to happen on a regular basis. Breaking two of the straps (which are rated of withstanding 700Kg breaking force) that held the RIB down for example, gives a good idea of what was going on up top - yet the crane, RIB, supports for it and the radar arch etc all are fine - not even any stress cracks in gel coat around their fixing points are evident.

The real disappointment was this trip was a one off and I had bought a new DSLR cameras and microphone to capture it and not suffer the same wind noise and issues of past Blogs. Sadly getting used to the new camera, forgetting to turn on the external mic, not being used to the boat and so on all conspired to cause the resultant footage (first part live tonight) to be pretty poor and does not tell much of a story but at least you get to see some boaty action at sea which is always nice I find.

 

[MapisM]

cameras never convey true sea conditions

Absolutely true.
But even if I'm perfectly aware of this, the title "F7 going on 8" in the last above video is questionable to say the least.
No white foam, no breaking waves, WTH? I wish F7 to 8 seas were anything like that! :ambivalence:

 

[Hardmy]

Hi,

the original GZ curve is not beneficial in practice because it is just a theoretical calculation that does not take into account the realities of real life. Different shapes of wave, wind, gust, your accessories load vs standard boat.

Sure it depends on the wave conditions etc, but this theoretical calculation does give a basic idea about a boat's stability. I'd love to find similar comparison for mobos:

 

[Portofino]

I swapped from those rule cheese thingy s to electronic sensor type in the ER for the bilge pumps
€70 each though but I think worth it .
Just have to dab a wet sponge on the contacts to test .

Looks like a F5 tops in the vid to me ,—— sat in an armchair

Anyhow it’s what the bilge pumps are for ,most boats inc mine on a long “ difficult “ passage will pick up bilge water in the ER .
More from the cockpit being drenched from water coming over the glass and finding its way through the joints in the cockpit sole / ER ceiling .
There are huge scuppers but until it drains out .
At least you guys had a wheel house to hide in .:encouragement:

 

[londonrascal]

Well that went faster than planned, here is the first leg - Plymouth to Weymouth:

 

[londonrascal]

The video of Dungeness was filmed with very a high telephone lens - I can say that the winds where the boat was were hitting 37Kts. Having a look at Beaufort scale that is indeed a F7.

I took a wind meter with me, you will see I tried using this on camera in the Solent when it was calmer to show the the mic wind sock performing. I wish I had also filmed me using it when we are off of Dungeness to have hard evidence of actual wind conditions.

You guy's though, cor blimey lol - first we took too much of a risk in bad weather on a new boat, and now video is coming in it was not looking rough enough from something shot a few miles inland of us.

Here are some more images which say a little more about the conditions away from the shelter of the beach: