RYA Beaufort wind scale. Interpretation?

[steveeasy]

Hi,
Just reading RYA Dayskipper shore based notes booklet. Thought id glance through the section that covers Beaufort wind scale section. F6,7,8,and 9 contain the following. Power = displacement speed. Thought about it and quite frankly have no idea what they mean by this. can anyone make sense of it?

Steveeasy

 

[KevinV]

That planing boats should not (cannot) go over displacement speed in those conditions perhaps?

 

[Greg2]

It appears to be a reference to motor boats, many of which would have to slow down to displacement speed as opposed to being on the plane. Displacement speed being the speed that a hull will go without lifting out of the water onto the plane.

 

[steveeasy]

Hi
Ok had not considered it from that aspect. Whilst im not really the best person to make comments on such a book, I cant help think the entire book is written with little understanding on how its contents are interpreted by a reader.

Steveeasy

 

[ylop]

That planing boats should not (cannot) go over displacement speed in those conditions perhaps?

Yes - you’ll either break the boat or break the people on it if your try to plane in properly nasty conditions. Depending on the powerboat/engines/seating/crew you may be able to plane at the lower end of that range.

 

[ylop]

Hi
Ok had not considered it from that aspect. Whilst im not really the best person to make comments on such a book, I cant help think the entire book is written with little understanding on how its contents are interrelated by a reader.

Steveeasy

I think it was intended as course notes to sit alongside a series of lectures from someone who knew what they were describing rather than a text book that explains it in detail. I’ve never understood why it wasn’t better written a 3x as long for 3x the price!

 

[tillergirl]

Absolutely correct ylop. These are notes to facilitate students on courses. Power = displacement speed means exactly that; don't expect to be able to plane in those wind speeds.

 

[johnalison]

Absolutely correct ylop. These are notes to facilitate students on courses. Power = displacement speed means exactly that; don't expect to be able to plane in those wind speeds.

In that case, why not say so? It was the interpretation that I came up with, but it’s hardly English.

 

[billskip]

In that case, why not say so? It was the interpretation that I came up with, but it’s hardly English.

Probably an Irish edition..

 

[steveeasy]

Power = displacement speed

Not being a Motor boat. is the above relevant at all to a sailboat regarding the Beaufort scale. I dont think so. F10 Survival conditions!!. Why not just stick to a clear and concise explanation of conditions expected in relation to the recognised scale.

Steveeasy

 

[tillergirl]

In that case, why not say so? It was the interpretation that I came up with, but it’s hardly English.

They are just notes, that's why. It does make sense when each wind speed for sail and power is read through. If it 'were' prose it would take two pages of words. They are notes to save students having to make notes. Take for example: 10 Storm ..... Survival conditions. 11 Violent Storm ..... Survival tactics. In a lesson the difference would be explained. The Notes are intended to prompt the discussion in the lesson. Next is 'Passage Planning', basically a series of topics that clearly need more explanation.

 

[tillergirl]

Power = displacement speed

Not being a Motor boat. is the above relevant at all to a sailboat regarding the Beaufort scale. I dont think so. F10 Survival conditions!!. Why not just stick to a clear and concise explanation of conditions expected in relation to the recognised scale.

Steveeasy

Probably the bit about '6. ..... Sail = reef main and reduce headsail' is about the sailing boat.

 

[steveeasy]

Probably the bit about '6. ..... Sail = reef main and reduce headsail' is about the sailing boat.

Oh right. So its not a physics thing then. its sail = reef. Power =displacement. Fully understand the concept.

Steveeasy

 

[Dellquay13]

In that case, why not say so? It was the interpretation that I came up with, but it’s hardly English.

People with power boats capable of planing would have no difficulty with the meaning. Once you have knocked the fillings out of your teeth trying to plane in rough conditions you quickly learn the lesson.

 

[Irish Rover]

Probably an Irish edition..

Is that meant to be funny?

 

[billskip]

Is that meant to be funny?

I know many many Irish people, I was married to one, I lived in Dublin, I know they have a brilliant sense of humour....

 

[justanothersailboat]

Saving people from having to take notes seems dubious to me. I take notes to commit things to memory. If I wrote it down I very rarely need to reread it. If someone else wrote it down I will have to reread it often.

I have that book and don't think it very useful. It's carefully designed to cover the entire syllabus without risking helping someone get the same level of competence without doing the course. As a result it is no use to man or beast. Still, it keeps the publishers of alternatives in business.

 

[RunAgroundHard]

The ebooks, including Day Skipper Shore Based, have basic immersive reading features, on page note taking, highlighting, embedded video, sequenced graphics to display how a concept would be used in the real world, share and email features, thumbnail page scroll, highlighted and bookmarked search and zoom features. Example, on the cardinal mark topic, there is a graphic of the cardinals buoys. Tap the buoy and you see the light characteristics of the flashing buoy and the standard light characteristic graphic changing as the sequence progresses.

As aids to learning they do the job, but there are better formats e.g. web browser style solutions, where content is not restricted to a linear progression. The fact that they pretend to be a book with pages and graphics that split across two pages, separated by a visual spine, suggests traditional thinking towards learning still has it's supporters at the RYA.

Still, the digital books are superior to the paper books, especially the video features and set by step graphics for demonstrating concepts, but more of this could be included. An obvious benefit is that they can be updated faster and more frequently than the paper based versions.

The Beaufort Windscale page is odd, it just sort of hangs there with little immersive content beyond a zoom of the images. The text associated with "displacement speed, stern waves" could be linked to a better description of displacement speed, what it is, the differences, even link to stability section of other parts of the syllabus.

 

[justanothersailboat]

That's interesting to hear, runagroundhard. They may be limited to book-like navigation by having to adapt print material or by having to make stuff that works in ebook stores or just by budget, but it sounds like the extra media/interpretation is valuable.

Pity the RYA radio ebooks were just flat page scans... those were poor value... only bought them because I left the paper one at home right when I most needed to swot up. I shall check carefully in future which digital versions actually have extras that make sense.

 

[steveeasy]

Now would this have not been a much clearer example to aid interpretation. the booklet is a training aid and should be as informative as possible. clear and concise.



Steveeasy