New Cowes breakwater

Hayling Island SC has moorings just inside Chichester harbour entrance, and I can say from personal experience as an ex member it gets a touch lumpy there, my large tubed Zodiac inflatable was swamped.

Several of the the dayboats off Itchenor were sunk in the 1987 Hurricane, but that like the sad affair off Cowes was largely a result of over-optimistic owners with more money than sense, leaving boats with no self draining cockpits, no auto bilge pumps and no covers out on exposed moorings...:rolleyes:
 
Seajet said:
So I have to ask, why were you motoring in with a following gale and a transom mounted engine ?!
Click to expand...

I never said it was a following gale I said it was a northeasterly which was pushing me on to the rocks sideways. To get off the rocks the wind was on the nose so I chose to use the engine rather than wreck the boat!
 
prv said:
My point wasn't so much about the degree of danger, but the distinction between an entrance (which the mouth of Chichester certainly is) and the body of a harbour. At Chichester, the harbour mouth and bar would certainly be dangerous in an onshore gale - but a yacht already inside the harbour and tied up would not be unduly troubled. Whereas when the wind blows into Cowes, more or less everywhere north of the chain ferry is getting bounced around, which covers a lot of pontoons and moorings and so on that in a proper harbour would be sheltered. I was saying that they're different situations, so claiming that one is worse than the other doesn't make sense. Chichester bar must be much nastier than Cowes, but you don't try to leave a boat alongside a pontoon on Chichester bar.

Last time I went into the Medina with a strong northerly and an outgoing tide (perhaps not springs though) I had no intention whatsoever of stopping anywhere north of the chain ferry. Maybe your northerly had enough east in it for some parts to be sheltered; nowhere I saw looked remotely tenable until south of the ferry. We ran right up the river under mizzen and staysail, including through some standing waves just before the ferry, and dropped sail just off the Folly.

Pete
Click to expand...

I completely agree - sorry I was responding to the danger part only and nearly edited my post to say I agreed with your not a harbour assessment but then didn't as the pub beckoned :)
 
bedouin said:
If you want a serious answer. Diffraction may cause a bending of the wave around the breakwater - but it should not cause an issue. Firstly if I remember my A Level physics from several decades ago, the amount of diffraction will only be significant if the wavelength of the incident wave is a significant proportion of the gap through which it is moving - which is unlikely to be the case here. Also the diffraction will cause a convex curved wavefront that won't be focussed at any point. (Now if you had two you might get some interesting interference patterns). Over all the amount of wave energy reaching the moorings will be much less so they will certainly benefit.
Click to expand...

The point is, there are two sources, the two ends of the breakwater.
The wavetrains coming from these two sources 'interfere' in some places they subtract, in others they add.
It's a classic GCE physics demonstration, although it's usually done with two gaps in a barrier because the effect is clearer.
It is an analogy of the 'Young's slits' experiment in optics.
 
lustyd said:
I never said it was a following gale I said it was a northeasterly which was pushing me on to the rocks sideways. To get off the rocks the wind was on the nose so I chose to use the engine rather than wreck the boat!
Click to expand...

LustyD,

well I don't quite get why the engine on the transom was better than the sails, but I know you're experienced and you were there and I wasn't !
 
Seajet said:
LustyD,

well I don't quite get why the engine on the transom was better than the sails, but I know you're experienced and you were there and I wasn't !
Click to expand...

Sadly, not every boat will go to windward in strong winds as well as an A22. If most of us want to go upwind at 20 degrees to the wind and at 10 knots we would use an engine :p

I know what you mean though, biggish seas where the outboard spends 1/2 the time out of water tends to be inefficient but may be better than a bilge keeler with a baggy rolled genny.

The fact is that it worked so was a correct decision. Sailing may also have been a correct decision as it may too have worked.
 
jac,

the day I get 10 knots at 20 degrees to the wind, rest assured you'll be among the first to know ! :)

I don't think there's any dishonour in using a boost from the Iron Topsail - it can get one across the Channel in light winds before fatigue sets in and / or the pubs close !

I was just surprised to hear of Cowes being spoken of as dangerous, having been there often; the boats which were photographed sunk could have been on any paddling pool, there's no helping some boat owners.
 
Seajet said:
jac,

the day I get 10 knots at 20 degrees to the wind, rest assured you'll be among the first to know ! :)

I don't think there's any dishonour in using a boost from the Iron Topsail - it can get one across the Channel in light winds before fatigue sets in and / or the pubs close !

I was just surprised to hear of Cowes being spoken of as dangerous, having been there often; the boats which were photographed sunk could have been on any paddling pool, there's no helping some boat owners.
Click to expand...

The fact that you have not yet seen something does not mean it hasn't happenned :D
 
Seajet said:
...I was just surprised to hear of Cowes being spoken of as dangerous...
Click to expand...
Anywhere can be described as dangerous in certain conditions, just as most of the time Chichester cannot be described as dangerous. Every winter there are days the Red Jet and car ferry are unable to enter in some tide and wind combinations, they are days when leisure sailors probably choose not to be out. The sunken boats were photographed after the gale, not during it.
 
lustyd said:
The fact that you have not yet seen something does not mean it hasn't happenned :D
Click to expand...

Well I've seen the trail log go past the 10 knot stop surfing down waves, also saw a UFO along with many others, and while I wasn't there personally I have it on good authority that a lightweight Landrover exceeded 100mph when dropped from a Hercules without a parachute...:)
 
Seajet said:
Well I've seen the trail log go past the 10 knot stop surfing down waves, also saw a UFO along with many others, and while I wasn't there personally I have it on good authority that a lightweight Landrover exceeded 100mph when dropped from a Hercules without a parachute...:)
Click to expand...

And on 18th August 2011 I've saw and experienced Cowes entrance as SotonMet recorded 29kt gusting 31kt 061degrees. Bramblemet errors for the date, I think it may have been during the outage when it had been hit. that day I saw 9kt on my log although I was not concentrating on that but rather on not falling out of the boat since I lacked a LJ or tether, having set out with a forecast F3. I have since learned this lesson :)
 
lw395 said:
The point is, there are two sources, the two ends of the breakwater.
The wavetrains coming from these two sources 'interfere' in some places they subtract, in others they add.
It's a classic GCE physics demonstration, although it's usually done with two gaps in a barrier because the effect is clearer.
It is an analogy of the 'Young's slits' experiment in optics.
Click to expand...

That's my concern. Happy to admit that the engineers should know more about it than me, but then again, they were pitching to get the contract.
 
I was at a preliminary consultation meeting with the MMO (in Brighton) as part of its scheme to create usage plans for the South Coast. It was meeting with interested parties to find out existing uses, and explore what changes users might suggest. The MMO expert leading the break-out session I was involved in spelt the yachting capital of the UK 'Cows'. I wouldn't rely on the organisation's expertise without some reservations!
 
Can I defend my profession of Civil Engineering - Most Inginers kant spel as i no!! But none of the bridges , flyovers, and structures that I have designed have fallen down ..................yet!!

Seriously I have been involved with some marine investigations - admittedly, mostly concerning errosion and the level of knowledge and ability to model these situations (not my area of expertise I would add) is pretty good these days. Biggest failures are usually in underestimating how quickly the 1 in 1000yr storm will strike!!
 
l'escargot said:
I wouldn't be inclined to write off the expertise of an entire organisation on the basis of one employee misspelling the name of a town.
Click to expand...

By and large they displayed a huge depth of knowledge of the more arcane aspects of the planning system, and bugger all about the sea. I think that is why they were consulting, to find out what it is actually used for.

The results of their deliberations are essential reading if you have difficulty getting to sleep.

http://www.marinemanagement.org.uk/marineplanning/areas/documents/south_draftspar.pdf
 
Twister_Ken said:
That's my concern. Happy to admit that the engineers should know more about it than me, but then again, they were pitching to get the contract.
Click to expand...

With the breakwater being much longer than the wavelength of the waves, a lot of wave energy is going to be reflected, so thats energy that isn't reaching inside the harbour. There'll be some diffraction around the barrier, but you're going to get a shadow rather than a lens.
 
You must log in or register to reply here.

Share this page

Top