Portland Race: how many tides meet, thereabouts?

Greenheart

Greenheart

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Just saw Sir Donald Sinden talking about the making of The Cruel Sea...telling how they took the ship to Portland Bill, looking for rougher water than was available elsewhere, for cinematic effect. Sinden says he understood that seven tides meet at Portland Race...

...is that right? Is it even possible?

CorvetteCoreopsis.jpg
 
Seajet said:
I agree, maybe he was confusing it with one tide doing 7 knots !

Not my favourite place for a relaxing time.
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7 knots seams a bit much. Not that I am an expert on Portland Bill.
I think Corrievrechan runs up to 7Kn as does Cuen and a few other Narrows may come close.
Menia Straights?
But Portland Bill. No doubt it can be rough when winds aginst the current.
 
Uricanejack said:
7 knots seams a bit much. Not that I am an expert on Portland Bill.
I think Corrievrechan runs up to 7Kn as does Cuen and a few other Narrows may come close.
Menia Straights?
But Portland Bill. No doubt it can be rough when winds aginst the current.
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I don't have the books to hand, but I think you'll find 7 knots off the Bill at times - I was referring to Sindens' ' 7 tides ' in the OP though.
 
tides

"Just saw Sir Donald Sinden talking about the making of The Cruel Sea"
Just had a quick look at his biography, I see that he is 89 years of age so probably a bit gaga, seems highly unlikely that he set foot outside of Pinewood studios during the making of that movie, perhaps a few shots at Portsmouth docks.
But no he has got it wrong, I did a great deal of scuba diving in the area during the seventies, and I can assure you there is only one tide, get it wrong and you are in trouble, it rips.
 
LadyInBed said:
Just one Tide at a time - it converges and goes west round the Bill or converges to go east.
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Surely that is what we would refer to as "tidal flow", which is not really the same thing as understood as a "tide", as in "high tide" etc.

I bet if Sinden had used nautically precise language they would have asked to re-record with him saying something more impressive and/or woolly!

Mike.
 
Just happen to be on the boat so checked my log. The last time I went West we picked up a good ebb before Peveril ledge so when we got to St Albans we had full flow beneath us. We were motoring with only 5 kts of wind. Over the next hour we covered 10.7 miles. The following hour once into Lyme bay we covered 7 miles.
 
see
http://www.visitmyharbour.com/articles/article.asp?arturn=3181

quote with regard to the race itself
"the spring rate is about 4-5 knots in a west-south-westerly direction, and the west-going stream attains its greatest rate, 7.2 knots at springs in a direction 245o, - 0545 Devonport (+0100 Dover)."


" Through the greatest observed spring rate of the stream off the Bill is 7.2 knots, at a position 1-3 miles 160o from the lighthouse, yet stronger streams, possibly up to as much as 10 knots, may be found in the immediate vicinity of, but not necessarily in, the race (see below).

There is very considerable excess south-going stream at this position, and appreciable excess south-going stream at a position 4-7 miles 171o from the lighthouse.

Portland race is caused by the very strong south-going streams from both sides of the Bill meeting the east- and west-going streams off the bill, and its violence is increased by the sudden decrease in depth off the bill and inequalities of the bottom on Portland ledge."


makes sense to me as I've always tried to time the inshore passage close to slack water and even then there's a considerable kick from the tide.
 
I once broke down on a rib in the Jack Sound just off Skomer Island (Pembrokeshire), that was bad enough.:o
 
Lordy! Once Scotland has all that electricity, I expect they'll be busy on the Clyde, building an angle-grinder the size of a wind-turbine, so Scotland can be permanently detached from the burdensome southern sack o' craps. I mean, Sassenachs. :D
 
galadriel said:
Just happen to be on the boat so checked my log. The last time I went West we picked up a good ebb before Peveril ledge so when we got to St Albans we had full flow beneath us. We were motoring with only 5 kts of wind. Over the next hour we covered 10.7 miles. The following hour once into Lyme bay we covered 7 miles.
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Back home now, I should just add that we were motoring at 6kts and it was not quite yet springs, and not a big spring at that. So at the top of a big spring I'd say 7knts is quite possible.
 
galadriel said:
I cant find any reference in the thread, would this be a BBC program?
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Indeed, yes. A programme called "Fifties British War Films: Days of Glory"...

http://www.bbc.co.uk/programmes/b01pkj2m

...I never got the idea that Donald Sinden was losing his mind, or too thespian to have a foot in the real world...

...but the 'seven tides' reference did make me wonder whether he knew a great deal that I don't...or perhaps, very little! :D
 
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