Neeves
Well-known member
I'm a glutton for punishment
Most people have had an anchor drag. I wondered if anyone had thought back on why it dragged?
According to all the holding capacity tests, in good clean sand, an Old Gen anchor of around 15kg will have a UTC of about 1,000kg and a NG a hold of about 2,000kg - far more hold than necessary for the yacht sized to the anchor - as long as the tension is in one direction and that tension is increased steadily (not necessarily valid for most anchoring situations).
Consequently its not hold, per se, that causes the anchor to drag - but some other characteristic(s), chop, yawing, poor seabed (not that ideal sand, beloved of people testing anchors!), clogged fluke, change of wind direction, wrong anchor, short scope etc
Without getting into my anchor is better, or bigger, than yours - what conclusions have people drawn on why their anchor dragged.
Contradicting myself - once when I was testing a whole range of anchors we anchored for lunch using a 5kg Spade and then 5kg Excel - we dragged with either, in soft sand under fairly benign conditions. So size, at the extreme, does matter (we continue to normally use a 15kg anchor (or its equivalent) - which does not drag). We dragged using a CQR with out J24, a combination of not accounting for tide, we had only gone for lunch, but the chop picked up to something quite large and I suspect it, the chop, was the cause rather than the change in depth of water.
Jonathan
Most people have had an anchor drag. I wondered if anyone had thought back on why it dragged?
According to all the holding capacity tests, in good clean sand, an Old Gen anchor of around 15kg will have a UTC of about 1,000kg and a NG a hold of about 2,000kg - far more hold than necessary for the yacht sized to the anchor - as long as the tension is in one direction and that tension is increased steadily (not necessarily valid for most anchoring situations).
Consequently its not hold, per se, that causes the anchor to drag - but some other characteristic(s), chop, yawing, poor seabed (not that ideal sand, beloved of people testing anchors!), clogged fluke, change of wind direction, wrong anchor, short scope etc
Without getting into my anchor is better, or bigger, than yours - what conclusions have people drawn on why their anchor dragged.
Contradicting myself - once when I was testing a whole range of anchors we anchored for lunch using a 5kg Spade and then 5kg Excel - we dragged with either, in soft sand under fairly benign conditions. So size, at the extreme, does matter (we continue to normally use a 15kg anchor (or its equivalent) - which does not drag). We dragged using a CQR with out J24, a combination of not accounting for tide, we had only gone for lunch, but the chop picked up to something quite large and I suspect it, the chop, was the cause rather than the change in depth of water.
Jonathan