R'sand? What went wrong?

NUTMEG

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www.theblindsailor.co.uk
Finally brought Lady Jayne round from BYH to her home port in Maldon yesterday. Hadn't really planned to, meaning simply to shift her upriver to Bridgemarsh. However, as we left the marina a little before low water, wind and weather looked perfect so on impulse we turned to port and headed out of the Crouch. Motor sailing, we arrived at the R'sand with a shade over 2.4m of tide showing. Our course north took us over sand with drying heights of between about 0.7 give or take. The new boat (Cornish Crabber Mk1) draws less then a meter with the plate up, so we should have scraped over the sands. We ran aground four times and had to anchor and wait for water twice.

No panic as wind was light and no swell.

Are the Imray chart and the East Coast Pilot chartlet that out of date or do the drying heights really change that much?

Must be a scary place in a blow with a big swell running on a falling tide.

The sand feels like concrete after the Blackwater mud!

Arrived in Maldon at 18:30 about 1/2 hour before HW so a good trip.

Merry Christmas by the way.

Steve
 
Agreed...

... we arrived about 2 hours into the flood. But what I do not understand is that if the drying heights are shown as less then a meter, we draw a meter and the tidal prediction showed that for Holliwell Point we had 2.4 meters of water we should have cleared the banks with nearly half of a meter to spare. Do the sands really change that much? Or, as is likely, have I have forgotten something vital from my Dazedkipper course?

As I said not a problem just curious.

Steve
 
... we arrived about 2 hours into the flood. But what I do not understand is that if the drying heights are shown as less then a meter, we draw a meter and the tidal prediction showed that for Holliwell Point we had 2.4 meters of water we should have cleared the banks with nearly half of a meter to spare. Do the sands really change that much? Or, as is likely, have I have forgotten something vital from my Dazedkipper course?

As I said not a problem just curious.

Steve

I don't know where Holiwell point is but the difference in CD between the Raysand buoy and sandbank is about 5.5 metres so you would have needed 6.5m at the buoy. That would have been nearer HW on such a neap tide.
 
I am sure you are right. Holliwell Point is shown on Navionics UK and Holland chart as being just to the north of the mouth of the Crouch. There is a tidal station there. A case of technology being no substitute for experience!!

Thanks mate

Steve
 
... we arrived about 2 hours into the flood. But what I do not understand is that if the drying heights are shown as less then a meter, we draw a meter and the tidal prediction showed that for Holliwell Point we had 2.4 meters of water we should have cleared the banks with nearly half of a meter to spare. Do the sands really change that much?

Steve

I would be interested in the date of the Imray chart? The latest does not show a clear passage of less than 1m drying - because there isn't one. I didn't think East Coast Pilot had a chartlet of the Ray Sand.

There is a chart from 2011 which is the latest data (I'll do it again in the Spring) - which is FREE!!! - http://www.crossingthethamesestuary.com/page6.html

This shows best water to the east of the line of buoys - from memory around 000.59.600E where the 'best' drying height of 1m is briefly encountered (elsewhere its more). I guess though you could have expected to have cleared over if you had 2.4m at Holliwell Point. However you are talking about a tidal prediction I guess - you must be since there is no live tidal gauge there. Timing can be out sometimes on Belfield - not drastically but if it combined with a tide not living up to prediction at that state of the tide then a half hour can make a bit of difference and that early as has been stated would have had you bumping as you did. Having checked on the actual tidal heights at Sheerness on Friday, HW did underperform slightly but by only 0.2/0.3 of a metre and the tide was 30 minutes earlier than predicted on Belfield.

All that's just anorak stuff, you wuss early - but didn't you do well to get all the way round.
 
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Well done Steve. Sounds like you had an interesting time ploughing the R'san.

I'll look in to cast an enquiring eye over LJ during the week.

S B
 
You made it through - great. Waiting for water when the southern safe water mark lays over on its side, dry on the sands, can be amusing. Especially so if you associate red and white safe water marks with water and there is still water to the east of the mark!
 
Tillergirl...

Of course it was your chartlet to which I referred. And my Imray chart was not on the boat so Iwas using Leisure folio's 5607-3 and 5607-2 and Navionics on an iPhone as back up to the chart plotter.

All good fun, though! A silly film of our mini adventure is now on the blog.

Merry Christmas mate
 
Of course it was your chartlet to which I referred. And my Imray chart was not on the boat so Iwas using Leisure folio's 5607-3 and 5607-2 and Navionics on an iPhone as back up to the chart plotter.

All good fun, though! A silly film of our mini adventure is now on the blog.

Merry Christmas mate


Excellent, excellent. really enjoyed that even if it did look cold.

I think she looks great and look forward to seeing you out there when it gets a bit warmer (for me that its)

Happy Christmas - and a prosperous New Year!
 
Sat on the bottom is a sort of east coast theme, it's not the disaster the south coasters seem to think, then again it's not as hard either.
Which way was the wind blowing? It can hold a tide back by an hour if conditions are wrong, been caught out entering the ore.
 
Ahh, wind...

... Was westerly, so dead offshore. Plus floodwater flowing out of the rivers. I wonder if combined effect could have delayed the tide?

Hope you had plenty of turkey chaps, feel slightly ill!!
 
It was a good day to choose, and it sounds as if you did it the "touch and go" way, which is the proper East coast method! We were looking out for you at Bridgemarsh, but it sounds as if you took the only decent day to do the full passage. Well done
 
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