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Old 17 December 2007, 12:28   #11
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Thanks for all the feedback guys.

Just to clear up some points.

The pacing isn't being taught by a PBI.
This isn't in the UK.
This has nothing to do with any RYA courses.

We feel that the application of contact pacing is appropriate for the tasks that we are completing, considering both the risks and benefits. For the specific reasons that Simon Hawkins has outlined. I do agree that for Joe Public pleasure powerboater, the applications are limited.

Can anyone suggest any answers to my original question?

Quote:
Originally Posted by whiteminiman View Post
Can somebody explain to me, exactly what the danger is... in a bit more detail than "the boat will get sucked around/under". I would like to understand exactly what the two boats will be doing and how they effect each other to create problems.
Cheers,
WMM
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Old 17 December 2007, 12:29   #12
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I have done this in real life many times, and done at the right speed in the appropriate conditions I believe it to be a very safe and stable way of transferring crew from one boat to another.
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When a boat looks that good who needs tubes!!!
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Old 17 December 2007, 12:46   #13
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the original question

hi, trying to give a little bit to the actual question;

I know there are folk on here who will give a much better explanation than me, but to offer some bits;
and I might have misunderstood your question;

if you want to do this, but dont understand what the danger is, then can I ask - should you be really thinking of doing this; or maybe getting someone who does understand the risks involved to do it?? -

I do like the fact that you have looked into it though prior to doing it, - good

I've just re read your original post, and see that you are happy doing this anyway?, so is it the science geek bit that you want to understand, or just that you'd never thought through all the risks, etc, (different drivers, crew, boats, weather, engine response, etc etc etc), and i dont mean that in a bad way, just trying to get a better idea of what you want.
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Old 17 December 2007, 12:49   #14
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Quote:
Originally Posted by whiteminiman View Post
Can somebody explain to me, exactly what the danger is... in a bit more detail than "the boat will get sucked around/under". I would like to understand exactly what the two boats will be doing and how they effect each other to create problems.

The dangers vary in degree with the types of vessels begin used.

The above quote I believe refers to the stern wave. If you miss judge your entry or exit between the bow and stern waves you'll end up riding over the stern wave and being sucked into the trough at the back of the boat. If you're dealing with a large powerboat like a Severn, the stern wave and trough are significant and could flip the boat.

Although the stern wave is less of an issue with two ribs, you encounter other problems such as one boat riding over the top of the other, especially when it's lumpy.



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Old 17 December 2007, 12:56   #15
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Originally Posted by Simon Hawkins View Post
It is very dangerous if carried out incorrectly
You could apply that statement to any boating activity.

Quote:
Originally Posted by Simon Hawkins View Post
What benefit is it to a student to learn pacing.
Quote:
Originally Posted by Doug Stormforce View Post
What gain does learning pacing have for most advanced students - very little
Now, lets see. Keeping correct distance from a leading craft, dangers of driving in a wash, correct angles and technique for powering through another boats wash, dangers of getting out of shape in another boats wash,
steering a dead straight line, use of throttle and trim for matching speed exactly whilst steering aforesaid straight line. For me, it's good for honing boat handling skills and will certainly be of use to those entering the commercial rib driving world.


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this is an obvious building block in learning high speed coming alongside.
It doesn't have to be done at high speed, it doesn't have to be done in a choppy sea and there's no need for full contact.

Anyway, the RYA say we can't teach it within the syllabus so thats that otherwise I would be teaching it.
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Old 17 December 2007, 13:05   #16
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Originally Posted by eilean mor View Post
I've just re read your original post, and see that you are happy doing this anyway?, so is it the science geek bit that you want to understand, or just that you'd never thought through all the risks, etc, (different drivers, crew, boats, weather, engine response, etc etc etc), and i dont mean that in a bad way, just trying to get a better idea of what you want.
I'm aware of the risks of doing it... I'm trying to understand why those risks exist. So yes, the "science geek" bit

Coming alongside something like a Severn, I can see the issues of the stern trough there. We're specifically doing it in SIBS or RIBS of similar sizes. Our biggest RIB is 9.5m and our smallest SIB is 3.4m - with another 7 boats in between.

Thanks for all the contributions.

WMM
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Old 17 December 2007, 13:24   #17
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Quote:
Originally Posted by whiteminiman View Post
in a bit more detail than "the boat will get sucked around/under". I would like to understand exactly what the two boats will be doing and how they effect each other to create problems.
I've no experience of pacing but I guess the forces will be created by the accelerated water between the boats having a lower pressure. When a fluid is accelerated, the pressure within it drops. This is the force which also makes your propeller function and makes the fuel issue into a carburettor.
The two boats will be displacing water and the water around them has to accelerate to enable it to get to the back of the boat to fill the hole where the boat would have been had the water not got to the back quick enough. So, when two boats close on each other, the water between them is squeezed and must accelerate faster than the water on the outside of the boats. This will cause a reduction in pressure between the boats so the water on the outside of the boats will push them together. I'm guessing that if the boats are similar and the water conditions are good then the forces will be reasonably balanced but if there are waves and the boats are rocking and rolling I would imagine it would be fairly easy for the side of one boat to ride up the side of the other. With a rib to rib it's fairly easy to imagine one tube on top of another and an unstable situation arising.

With dissimilar boats, it would be difficult to predict the behaviour except with a heavy boat and a light rib in contact you can guess which one is going to have most difficulty.

There must be other interfering forces from the under water bow wave but I've nae idea how they would interact.
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Old 17 December 2007, 14:16   #18
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If you feel your students would benefit from this kind of training their is nothing to stop you running pacing sessions outside of your RYA training
That's not what is says in the RYA web site that I quoted. The wording is "Carrying out pacing between powerboats at Training Centres is prohibited", not just that you shouldn't do it as part of an RYA course.

What is the situation generally with RYA schools offering off-syllabus training?

John
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Old 17 December 2007, 15:13   #19
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What is the situation generally with RYA schools offering off-syllabus training?

John
Interesting point. A few people I work with, including many of the UK fire services, have become centres to enable them to certify in house - then they certainly go and do things with their boats the RYA might not like.

Ultimately, the RYA simply accredit a centre to deliver certain courses correctly in a safe manner. They don't own the centres, or the boats, or employ the staff, so I'd have thought that telling centres they couldn't do other things would amount to restriction of trade.

But then again I might be wrong...

As to pacing, I think WMM sums it up perfectly in terms of what they need to do with it. Within the limited confines of a teaching course to leisure boaters I'd say there's better things to spend the time on, but in a specific environment pacing is a very useful skill, and like all things if done properly carries very little risk.
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Old 17 December 2007, 17:21   #20
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When I did my Instructors course, pacing was part of the syllabus.......
Yes, but back then, the pace was set by a chap sitting at the back banging a drum
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