Can the Mantus Anchor be used without the hoop/ rollbar? This is a common question we get from our customers?
First, to make sure we are all on the same page let’s address the purpose of the hoop/bail on the Mantus Anchor. Mantus Anchor when deployed will fall and settle on the ocean bottom in the correct orientation and set with or without the hoop.
The hoop is there to prevent an accidental flip, say the anchor hits a rock on the way down right before it lands on the ocean floor or rolls on a sloped ocean bottom, or the rode goes straight over the anchor as the anchor is facing the wrong direction. These situations would create the possibility that the anchor flips on its back. These are really rare events that one has to offset against the fact that competing anchor designs are not as likely to set in the first place. I believe, the danger of a failed set when using an alternate anchor design is much more real than an off chance that a Mantus without the hoop will end up on its back. Nevertheless we recommend that the anchor be used with the hoop when anchoring for an extended period of time if at all possible.
The likely hood of the anchor flipping on its back is inversely proportional to the anchor size. The bigger the anchor the less the likely it can end up upside down. See the figures below:
These large commercial anchors are designed without a hoop and if flipped are very comfortable on their backs, yet it is the design of choice. Why? Because multiple other advantages of this design outweigh a very improbable chance that the anchor would find itself on its back.
Many of our clients on smaller boats have a problem storing the Mantus with a hoop assembled because it does not fit in the designated anchor locker, which is often designed to accommodate a Dan-forth style anchor. These customers usually are small boat owners and anchor only for a few ours, even a small anchor can be used in this situation without the roll-bar with.
We did some testing with a 2 lbs prototype to ascertain the frequency with which a 2 lbs Mantus can end up on its back if used without the hoop on the initial set. Assuming that no attention is paid to how the anchor is deployed of the boat we got failure to set rate of 0.02 (2%) due to the anchor accidentally flipping upside down, incidentally this was the only reason for a failed set. This data validated our decision to make a hoop-less dinghy anchor.
And even though with larger anchors flipping upside down is exceedingly rare, and does not usually happen as the anchor rotates with changing winds or currents (see video below). If possible we do recommend the use of the roll bar/hoop when anchoring for extended periods of time to completely eliminate the risk of flippage.