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Old 23 July 2005, 17:50   #21
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i think your both drunk and does really matter im drunk
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Old 23 July 2005, 17:51   #22
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Perhaps I shouldn't have asked.
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Old 23 July 2005, 17:55   #23
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Quote:
Originally Posted by Louise
please explain to me the advantage of having tubes in the water in a following sea? (Cos I'm just a girlie! )
You haven't answered my question Jeff.
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Old 23 July 2005, 17:58   #24
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I think it's about the third from last sentence. The one where I used if instead of is. Did Richard miss that one?
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Old 23 July 2005, 18:00   #25
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Quote:
Originally Posted by jwalker
Given that wave characteristics are essentially 'now you see them, now you don't', having the stability of the tubes in the wallowing sea if a definite plus.
A following sea isn't necessarily a wallowing sea though!

I still don't understand how having tubes dragging in the water behind you as you keep 5 knots or so ahead of the waves is going to help?
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Old 23 July 2005, 18:15   #26
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liar liar bum's on fire!

Quote:
Originally Posted by jwalker
Please, someone else, is what I've written unintelligible?
Well your latest edit has improved things slightly now that you've changed the figures, but parts of it are still jackanory! Here's the ORIGINAL text before you edited it... (I've highlighted in bold red the bit you changed )
Quote:
Originally Posted by jwalker
I do that with my tubes in the water, it works fine. However, that technique is mostly only valid in a head sea. For the boats I've had experience of, the effect only really begins to happen at 30ish mph but it becomes reasonably effective at about 35mph+. Given that a reasonable sea is going to have waves advancing toward you at about 15-20mph then the combination of boat speed plus wave speed is in the region of 50+mph for the boat to start cresting the waves neatly. If you are in a following sea, then it would seam reasonable to assume that the boat speed is going to have to be in the region of 65+mph to achieve the same effect. However, because of the wave shape, it does tend to help by ramping the boat up the slope for the jump to the next wave so there is the benefit this gives. The upshot of all my blethers is, that you need a seriously fast boat to use that technique into anything but a head sea and even then the boat must be capable of a good turn of speed. And, if yo! u don't have very fast boat, in a following sea a comfortable speed to travel is just a couple of mph faster than the wave speed. This eliminates slamming and the boat doesn't attempt to dive into the face of the wave infront. Given that wave characteristics are essentially 'now you see them, now you don't', having the stability of the tubes in the wallowing sea if a definate plus. And, as I previously said, they're a plus in a beam sea too.

Tell me again why I don't want my rib tubes in the water...
Now let's have a look at what you were waffling, sorry blethering, about...
Quote:
...it becomes reasonably effective at about 35mph+. Given that a reasonable sea is going to have waves advancing toward you at about 15-20mph then the combination of boat speed plus wave speed is in the region of 50+mph for the boat to start cresting the waves neatly.
You're over-estimating wave speeds, from my experience, although it's likely that we've encountered different ranges of sea states. I've found that anything over 35kts becomes effective in a head sea, with 40kts (50mph) giving an exhilarating, smooth ride. Confused seas without any particular wave direction can be approached with this technique too. Think about why it works so well - you're presenting the least possible hull surface to the water so you dont hit much of it. Unless you have very low tubes, in which case you're beating the waves into submission with a couple of flabby sausages!

Quote:
If you are in a following sea, then it would seam reasonable to assume that the boat speed is going to have to be in the region of 65+mph to achieve the same effect.
Now you're getting carried away Jeff! In a following sea, your speed "through the water" (or at least relative to the waves) will be lower. Did you mean speed over the ground, or through the water? Speed through the water makes sense. You will only need a craft capable of 15mph faster than the waves to make comfortable progress. If you do 65+mph then you're heading for a big stuff!
Quote:
you need a seriously fast boat to use that technique into anything but a head sea and even then the boat must be capable of a good turn of speed. And, if you don't have very fast boat, in a following sea a comfortable speed to travel is just a couple of mph faster than the wave speed.
At last you're making sense! I wouldn't advocate the technique in a following sea of any great height, I didn't suggest so, you've just chosen to follow that line of argument.

You still haven't qualified why you need your tubes in the water in a following sea. And you won't, because you can't, because it's complete pish.

I'm off to open a cold one, maybe two, then I may be able to understand you!
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Old 23 July 2005, 18:19   #27
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Quote:
Originally Posted by Louise
A following sea isn't necessarily a wallowing sea though!
Given the content of the previous two sentences in the paragraph and your boating experience, I expected you to understand and know that a boat will wallow in the trough as the wave formation subsides due to it's cyclic nature.


Quote:
I still don't understand how having tubes dragging in the water behind you as you keep 5 knots or so ahead of the waves is going to help?
It's not just that they drag behind but that they also drag out to the side. This gives lateral stability to the boat and support to the stern while it is in a difficult situation. I appreciate that Scorps have very little tube to the stern so you may not have experience of the benefit.

Now your arithmetic is failing. I thought I said a couple of mph.

It would be worth swatting up what the water particles are doing inside a wave and how this effects the formation of the wave and it's motion through the water.
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Old 23 July 2005, 18:26   #28
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Jeez, I thought you were clever. Boat at 35 + wave coming toward you at 15 = 50 over the waves

Boat at 35 - following wave at 15 gives speed over the waves of 20. We were talking about travelling over the wave crests, weren't we?

I did originally say 65 rather than 50 and that's why I did a smillie at your comment.

Oh yeh, I agree, approximately, with your speeds. I thought that is what I said. (My tubes in contact with the water obviously help my boat to travel over the waves more easily. )
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Old 23 July 2005, 18:27   #29
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Quote:
Originally Posted by jwalker
I expected you to understand and know that a boat will wallow in the trough as the wave formation subsides due to it's cyclic nature
I don't recall 'wallowing' in any following sea I've been in - we've always cut through straight and true. The only 'wallowing' we do is when the boat is at rest.


Quote:
It's not just that they drag behind but that they also drag out to the side. This gives lateral stability to the boat and support to the stern while it is in a difficult situation.
Only 'difficult' if you haven't got on the throttle quickly enough, surely?

Quote:
I appreciate that Scorps have very little tube to the stern so you may not have experience of the benefit.
I've been in a boat that did and I didn't like the ride as much as in our boat.

Quote:
Now your arithmetic is failing. I thought I said a couple of mph.
OK so we're arguing about 3.75mph!

Quote:
It would be worth swatting up what the water particles are doing inside a wave and how this effects the formation of the wave and it's motion through the water.
Better still - explain it here please so we can all learn and discuss how it applies to the debate.
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Old 23 July 2005, 18:32   #30
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Nah, it's getting silly and I can't be arsed. I'm off to concentrate on Goldie Hawn on the telly. Night, night.
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