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MARCH 2016 http://www.yachtingmonthly.com 3

W

hat do you use as an anchor

cable – rope or chain? Most

cruisers have a strong

preference for chain. It’s

stronger than rope and more durable. It

doesn’t chafe, you need less ‘swinging room’

in anchorages, and it’s much less likely to get

wrapped round your propeller, keel or rudder.

Besides, chain just feels safer.

Rope has advantages, though. It’s a lot

lighter, so you don’t have a heavy weight in

the bow locker inducing a nasty pitching

motion at sea. It’s cheaper than chain, or at

least it can be, and it’s much nicer to handle.

With rope, you could drop anchor in 80

metres or more and then haul it up by hand.

You couldn’t do that with chain.

But when the wind pipes up, a boat that’s

anchored on rope gets blown around, yawing

with each gust and snatching at her cable. It’s

no fun for the crew and the forces acting on

the anchor, coming from various angles, can

loosen its grip on the seabed and make it drag.

Chain has a very useful property called

‘catenary’, by virtue of its weight. The effort

required to lift a heavy length of chain off the

seabed and straighten it out has a damping

effect, cushioning the forces of wind and

waves. That’s why most of us prefer chain.

Catenary isn’t a myth. It’s real and it works,

but only to a point. The myth, and it’s a

common one, is that it works in strong winds.

As Vyv Cox explains on p34, catenary stops

working when the chain is pulled straight,

around Force 6. Then, instead of damping the

forces acting on the deck gear and anchor, it

exerts a violent shock load on them each time

the boat snatches at her cable. Chain, it

seems, is actually worse in a gale than rope.

So what’s the solution? There are several:

either use chain and rig a stretchy rope as a

‘snubber’ to provide elasticity, or use a ‘mixed

rode’ – a heavier chain equal in length to the

depth you’re anchoring in, attached to a very

long rope (about ten times the depth). You

can also lower a heavy weight down the cable

to restore catenary, or set a riding sail on the

backstay to reduce the boat’s yawing. I can’t

tell you which of these is best, so I’m going to

try them all this season and report back if

I find out anything useful.

If you’ve figured out by trial

and error what works best for

you, please drop me a line.

‘Should we trust rope or chain?’

PHOTO: ALAMY

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PHOTO: GRAHAM SNOOK

Kieran Flatt, editor

[email protected]

VIEW FROM THE HELM

Yachts yaw about in a gusty anchorage, some worse than others. How each boat behaves depends on her ground tackle – see p