MacGregorSailors.com

I used a lightweight Fluke anchor, in the last storm that we got caught in, it held really well. It had 10m of 3/8" chain and then silver rope. The winds were strong enought to knock some other trailer sailers over - under bare poles. But the anchor held solid. When we went to leave, I could not pull the anchor up. As we were only in 3 metres of water, I went down to see what had happened. The anchor was wrapped around some concrete beams, that had been dumped there. So in addition to the 7kg anchor, there was another couple of hundred kilo's (think at least 500lb) of concrete holding us still.

Moral of the story - the bottom conditions are the critical factor in holding ability...