The meaning of 'scope' in a maritime context

It's not all photos of cats and people eating dinner! Anchors and anchoring page is worth reading, Sadler and Starlight has far more contributors than the owners' association website forum.

I can resist anything except temptation.

with apologies to Oscar Wilde.

I'm now intrigued.

Jonathan
 
So to be 'correct' we should say 'scope ratio' when we mean the ratio (and it satisfies everyone).

When spoken there is less room for ambiguity and clarification can be asked for. Here, with the 'written' word, to be useful, as has been mentioned, we really need to define length, depth, size of chain and vessel. Scope of 5:1 is pretty meaningless in 3m or 10m of water, with a 6mm or 10mm chain, holding a 7t x 38' cat or 12t x 45' mono etc.

I find it odd that the use of the word as a ratio might be commonly used and understood (and its use a s length, on the basis of posts, less common) but that it has not crept into print with an accepted and defined meaning.
 
Is there actually any conflict there? The scope is the length of cable/chain deployed when at anchor, and that can be expressed either as an absolute measure, or as a ratio of the depth.

In any case neither is 'correct' or 'wrong', their use is customary.

The obvious problem is that if I ask "what is your scope," the question gives no context regarding which I want to know.

The US Navy and the US Coast Guard both formally define scope as a ratio.

I can understand differences between British and American usage, but confusion between Brits is unfortunate indeed. I'd be fine with coining a new word if it added clarity.
 
The obvious problem is that if I ask "what is your scope," the question gives no context regarding which I want to know.

Are you sure about that?

if I sail into a small bay and there is another boat already anchored there and I pull close enough to call across "What is your scope, please?" and he calls back "5 to 1" I can look at my depth reading, see that we're in 5m of water so he must have 25m of chain out. Simple. :)

Richard
 
Are you sure about that?

if I sail into a small bay and there is another boat already anchored there and I pull close enough to call across "What is your scope, please?" and he calls back "5 to 1" I can look at my depth reading, see that we're in 5m of water so he must have 25m of chain out. Simple. :)

Richard

Does anyone ever actually ask that though? I've never been asked or asked about scope, it's always "how much chain have you got out" And anyway the scope will vary depending on state of tide, so when you look at your sounder your 5 : 1 might be 25m at low water or 75m if there's 10m of tide to go.
Half the boats won't even have heard of scope... ;)
 
Are you sure about that?

if I sail into a small bay and there is another boat already anchored there and I pull close enough to call across "What is your scope, please?" and he calls back "5 to 1" I can look at my depth reading, see that we're in 5m of water so he must have 25m of chain out. Simple. :)

If you ask how much rode they have out, you'd save yourself all that complicated arithmetic. Of course you might have to explain what "rode" was. (Is any other language quite so rich in ambiguity as English?)
 
I'm arrogant and assume no-one knows these fancy words, scope?!, rode?! and must be one of those asking GHA 'how much chain have you got out' (no insult intended GHA:) ). I also assume they have no idea and keep as far away as possible.

A rule of thumb for the uninitiated here was - anchor next to anyone with a windgen - they are long term cruisers and know what they a doing. Being a honey pot has its downsides.

I do know there is a problem when the boat just completed anchoring next to us asks, without raising their voice 'do you think I'm too close'. My answer is - 'if you can talk to me without shouting you are FAR too close!'

In tight anchorages we ask, as above.

Scope, the ratio, is too ambiguous - do they include freeboard, when did they calculate that scope (low or high tide)?? Mind you they may just throw a figure out for length deployed as they might not have bothered to check :(

We do like less busy anchorages.

Jonathan
 
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Clearly ..... but it is likely to die through a non-understanding of the use of emoticons. :encouragement:

Richard

But you mean there are rules!

Agreed - there seems to be whole subsection of the population 'inventing' them (do people get paid?), its difficult enough sharing a common language with the Mother country without having to interpret a geometrically increasing number of designs.

Jonathan
 
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