The Jordan Series Drogue was designed to be a deploy and hunker down storm device for surviving the worst the sea can throw at you. Don Jordan, when I spoke with him prior to getting my JSD, compared it to an ejection seat on a plane, where you pulled the handle and then let it take over. Then, when the seas have calmed down... you haul the JSD back aboard and go on your way.
Multihulls can heave to much like any sailboat. However, most multihulls are far safer if they retract their centerboards/daggerboards, since their ability to slip often helps prevent them from capsizing. The real problems with a parachute-type sea anchor
apply to both multihulls and monohulls IMHO.
The problem with a sea anchor
is that if it is properly sized, it will effectively stop the boat almost dead in the water—like an anchor
would. The forces on the attachment points are incredibly high, much higher than those experienced by a Jordan Series Drogue, and few boats have hardpoints that are sufficient to the task.
Also, the way a parachute sea anchor
loads up, is very different from that of a JSD. The parachute will suddenly fill and put a very high shock load on the boat and gear. Unlike a parachute-type sea anchor, a series drogue loads up gradually, as the boat moves forward on the wave crest and the drogue line
The Series drogue is designed to slow a boat down to a very slow speed, and prevent the storm's forces from capsizing or damaging the boat. Since the boat is still moving, the waves, even breaking ones, don't get a chance to clobber the boat. Tests and real world experience has shown that the JSD will pull a boat through a breaking wave and prevent the wave from capsizing the boat. The boats generally don't even get pooped seriously, since the boat and the waves are moving at relatively close speeds.
Because of the design, a JSD can't collapse if the wave hits it wrong, like a parachute can. It also doesn't have to be a specific distance from boat like a parachute sea anchor does, simplifying its deployment.
Finally, the amount of rode
you need for a parachute-type sea anchor is often bulkier than the JSD for the same size boat would be.
I hope this helps Cam.