T&T: Anchor,chain,rope specs and use

[Robin]

Wayne posted some good observations.

Another may be that when a boat is partially broadside to the wind it is
tethered at only the anchor (bow) end, so the stern naturally moves. This
reduces the relative strain on the anchor tackle from what might be expected.

For example, if when partially broadside,  the apparent area is doubled, the
force is not. You can think of bridge supports at the end of each span: each
support carries only half the weight. On a boat, when the wind is straight on
the bow, the area is less, but the full force is exerted on the anchor.

Offsetting this is the fact that a boat develops some momentum when swinging
and eventually most of this is absorbed by the anchor tackle.

If a 40,000 lb boat gets moving/swinging at 1 knot and is brought to a stop
over three seconds, the force is F = MA = M (V/T) =40,000 (1/3) or 13,334
lbs!!!

Now I'm sorry I did that calculation! ;it never really dawned on me it would
be so substantial. Is that ballpark accurate?? Seems awfully high!!!  Now I
wonder if two anchors one each on separate rodes, which reduces yawing, makes
a lot more sense than we generally give credit? Two anchors in tandem on one
rode doesn't  have that dampening effect. This also gives some insight into
the dramatic effects of seas which causes surging of anchored boats during
storms.

Rob Brueckner
Hatteras YF