Originally Posted by MedSailor
Personally I've always thought that, for my boat/crew/situation a parachute sea anchor will be the first line of defense for a survival storm if heaving-to is no longer a viable option.
After doing quite a bit of research on the same topic, I've decided that parachute sea anchors suck, because if you don't have the right amount of rode paid out to exactly match the period of the waves, it's going to jerk your boat to pieces. And even if you do get it matched up right so you're rising when your anchor rises and falling when your anchor falls, what happens if the wind shifts or the period changes? The much better option is a "series drogue," because you get the same anchor force but it's distributed along the line. I believe most series drogues are intended to be attached at the stern.
These guys have some videos:
Jordan Series Drogue
I have no personal experience with either, and I hear that trying to reel a series drogue in can be a real bastard once it's deployed, but I'll be trying the latter before the former.