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LETTERS

10 http://www.yachtingmonthly.com MARCH 2016

How to pass RYA Theory Exams (Feb 16):

Humblest apologies and three all-round

red faces after several readers pointed out

that three red lights means ‘constrained by

draught’ and not ‘aground’ as was stated.

No defence m’lud, but in mitigation we

were racing to get the issue out so we

could have a few days off for Christmas.

CORRECTION

Thanks for the Deb

Thank you very much for the enjoyable

review of the Deb 33 (Jan 16). It was very

accurate and covered all aspects of the boat.

As the owner of Red Martlett, a Deb 33 in

Poolbeg, Dublin, I feel she is really full of

character and a real pleasure to sail.

John Wedick

The Deb 33 won

many admirers

after our used

boat test (Jan 16)

PHOTOABOVE: JOE McCARTHY/YM

Stern-to mooring maths

Regarding your excellent guide to stern-to

mooring (Jan 16), one of the things that can

go wrong is to run out of chain before the

stern reaches the quay. This usually happens

12m

2-3m

SIMI

QUAY

12m

20m

12m 12m

56m chain

required

GRAPHIC: MAXINE HEATH

when the depth is greater than usual so the

skipper decides to drop anchor at four or

more boat lengths from the quay, instead of

the usual three. I use this formula:

Minimum scope = Depth + ((Boat lengths to

quay–1) x Boat length)

So if the depth is 20m and your boat is

12m long, dropping the anchor at four boat

lengths means you need at least 20 + ((4-1)

x 12) = 56m chain to reach the quay. If your

boat has only 50m of chain you will end up

short, meaning you need to haul it up and

start from scratch.

Typically Greek ports, where I first

encountered this type of mooring, are not

deep, but I did come up short in the Greek

island of Simi, where the depth was 30m!

Enrique Kariger, Madrid

Vyv Cox adds an anchoring tip: I know Simi

quite well. The depth at the quay is 2-3m

whereas the anchor is dropped in 20m or

more. Dragging is quite common as it takes

a while for the anchor to hit the bottom, by

which time the boat may only be a couple of

boat lengths from the quay.

I keep the boat stationary until the

windlass has lowered 20m, then motor

astern. I recall using around 45m of chain in

Simi. Fortunately the bottom is thick mud,

good holding.

Desmond’s been

We chose Glasson Dock on the River Lune as a

quiet place for the winter, but we didn’t bank

on Storm Desmond. This Notice to Mariners

highlights its repercussions:

■ No7 Buoy is in the approximate position of

the No8 Buoy

■ No8 Buoy is in a position between No

Buoy and South Bank Buoy

■ No12 Buoy is in position but upside down

(therefore no light showing)

■ No14 is on the beach

Gerald Davies

Anchoring in deep

water, it helps to know

you have enough rode

before you drop