You mad bro?
What kind of "reasearch" did you do??
Read a bunch of personal accounts of people who had problems with sea anchors, then learned about wave motion to figure out why.
When you're anchored firmly in a blow, does your boat get jerked to pieces?
"anchored firmly" is a very loose term when we're talking about a parachute that's moving in circles in one ocean swell, and my boat is bobbing up and down on another ocean swell two swells down. Please clarify it, thanks.
If you mean "anchored firmly to the ocean floor while my boat bobs in 20 foot seas," I can happily say I've never been forced to endure such a thing, and if I had, I can imagine it might jerk my boat about quite a bit.
When you're on a mooring in a blow does your boat get jerked to pieces?
I wasn't aware moorings existed out in the middle of the ocean where you might experience 20+ foot swells during a hurricane, and if such things did exist, I would be wary of tying up to them, for fear I get my boat jerked to pieces. Maybe you've had a different experience you'd like to share?
Now, in my boat, if I'm in less than 12 foot seas, there's no point in deploying a sea anchor anyway. I'm sailing it. The point of a sea anchor, as I understand it, is to deploy something, batten down, and go below if you get hit by a small to medium sized hurricane and you're too far to run for shore. Right? For that, you need to plan on 20 foot swells or more. When tied up to a parachute sea anchor in 20 foot swells, you need to understand something about how wave motion works. When a wave moves, the molecules that make up the wave don't actually move themselves except in a big circle. Read this:
Motion in the Sea -- Waves
So if you have your rode panned out to the wrong length, you can end up in a situation where your boat goes one way and your parachute goes the other way, once per wave, jerking your rode tight. Then in the trough it goes slack again as you and the parachute come together. Once per wave. I've read several personal accounts of people who didn't get this right when deploying in a hurricane, and they had to cut the damn thing loose. You don't have that problem with a series drogue, because the resistance to motion is distributed all along the length instead of at one spot at the other end.
I've also read some other accounts of people who are experienced at using parachute sea anchors, most notably commercial fishermen from New England where the practice is common, and they pay a lot of attention to how far out to pay their rode so they match the wave period. They will also reel it in or let it out if the conditions change. Seems like a certainly smart and prudent thing to do, that I just don't want to have to fool with if I'm just choosing among emergency gear.
What storms have you deployed a parachute sea anchor in, and what were the conditions? Did you pay attention to the wave period when you deployed it?