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Storm tactics, sea anchors and such for trawlers

BE
bob england
Sat, Apr 8, 2006 2:55 PM

I posed this exact same question sometime ago, when this list was first
started. I asked for real world, first hand, did it myself experiences. If I
remember correctly I asked "what were your thoughts just befor you pitched
your junk in the ocean ? "  I related my experience when caught in a storm
and needed to keep the bow of my sportfisher into the seas, I used my anchor
rode and a large plastic bait tank, it worked much better than nothing. The
response I got was very similar to the responses I am reading here, mostly
"book larnin" and "here's what I'm gonna do". Surely there are people out
there that can relate to us the physical difficulties not covered in the
books and how and why they determined to use the device, and the outcome.

I posed this exact same question sometime ago, when this list was first started. I asked for real world, first hand, did it myself experiences. If I remember correctly I asked "what were your thoughts just befor you pitched your junk in the ocean ? " I related my experience when caught in a storm and needed to keep the bow of my sportfisher into the seas, I used my anchor rode and a large plastic bait tank, it worked much better than nothing. The response I got was very similar to the responses I am reading here, mostly "book larnin" and "here's what I'm gonna do". Surely there are people out there that can relate to us the physical difficulties not covered in the books and how and why they determined to use the device, and the outcome.
MM
Mike Maurice
Sun, Apr 9, 2006 9:25 PM

This is the response I got from Don Jordan regarding the comments I
posted about this topic. My comments regarding his comments are below.

<<<<<<<<<<<<<<<
From: "Donald Jordan"
To: mikem@yachtsdelivered.com
Subject: Your note

Hi Mike,  Two comments
"deploying a jordan drogue from the bow is better than nothing"  Not
so.  It would be better to lie ahull..
"choice is a damaged stern or a rolled boat"  Not so.
The drogue has been though many storms including hurricanes with no
damage to the rudder, stern or companionway doors.
Keep up the good work.
Cheers,  Don

First things first. My original comments were not intended to tell
anyone what to do. There is such a gulf of understanding about the
use of drogues and such that the only tactic that makes sense to me
is to try to get people to THINK about the various tradeoffs, such as
placement, length of lines and bridles, strength of materials,
stretch of lines, chafe resistance, ease and safety of
deployment/recovery, etc.

The problem with the present day yachting community is that it is
inventory oriented, rather than engineering oriented. Drogue
usage(this includes parachute anchors) is an engineering problem. But
people seem to want to be able to go into a store and buy a drogue
off the shelf, ready to go, as if it were just another bag of stuff
to throw in a locker.

Now, Don Jordan's comments. Notice the easy to read part about the
bow being a poor deployment location, with which I never intended to
be taken seriously. But, Don makes the point with which I am inclined
to believe is correct that stern damage is a low risk. So, how are we
to evaluate this assertion of low risk?

Recall that the Jordan design strategy expects the boat to be
accelerated as a wave comes along. If the wave is none life
threatening then the stresses on the gear are minimal, the boat is
pushed around a bit and the wave pass by. If the boat reaches near
wave speed during such a pass, but even if some water is splashing
around the effects of striking the boat will be minimal as the water
speed and boat speed will be near the same.

However, if a real monster comes along which threatens to roll the
boat or pitchpole it, the Jordan will allow enough acceleration to
keep the boat speed and the wave speed close coupled, but prevent
catastrophic acceleration. If you can design a better "mousetrap",
then use it! And if you can't then I submit that the Jordan Series
Drogue is at present the best alternative.

By the way, I have a lot of experience with large following breaking
waves, some in high winds, and although I have not used the Jordan, I
have a high level of confidence that at the moment of possibly being
thrown out of control, the Jordan would perform as claimed. If I had
to take a chance on the boat taking damage on the stern, versus being
rolled or violently pitchpoled, I think I would go for the stern
damage. Now, I understand the misgivings that many people have about
exposing their stern to large boarding seas. I have the same nervousness.

So, here is my take on the problem. Long period waves are very high
speed, but the longer the period the less steep they tend to be. A
wave that is very steep and near to breaking, even in the open ocean
in deep water, is not moving at near the speed of the underlying
swell. It is by definition a wave out of character with the general
run of waves. Therefore, it is not nearly as fast, perhaps no more
than 20 knots, perhaps as little as 15 knots. Now this is more than
fast enough, if tall and steep enough to do real damage. But, if you
are running with and have some speed up, then any approaching wave
does not have accelerate your boat near as much to reduce the
difference in speed between the boat and itself. You are after two
things here, to reduce the difference in speed and prevent the boat
from being flung out of control  This difference in speed can't be
expected to prevent any and all stern damage, but you might be
pleasantly surprised to see what a huge effect it does have.

It will be a couple of weeks before I will be back to continue with
this subject. After tonight you are on your own.
Don is being sent a copy of this. It's too bad he isn't up to writing
extensively about all this.

Regards,
Mike

Capt. Mike Maurice
Tualatin(Portland), Oregon

This is the response I got from Don Jordan regarding the comments I posted about this topic. My comments regarding his comments are below. <<<<<<<<<<<<<<< From: "Donald Jordan" To: <mikem@yachtsdelivered.com> Subject: Your note Hi Mike, Two comments "deploying a jordan drogue from the bow is better than nothing" Not so. It would be better to lie ahull.. "choice is a damaged stern or a rolled boat" Not so. The drogue has been though many storms including hurricanes with no damage to the rudder, stern or companionway doors. Keep up the good work. Cheers, Don >>>>>>>>>>>>>>>>>>>>> First things first. My original comments were not intended to tell anyone what to do. There is such a gulf of understanding about the use of drogues and such that the only tactic that makes sense to me is to try to get people to THINK about the various tradeoffs, such as placement, length of lines and bridles, strength of materials, stretch of lines, chafe resistance, ease and safety of deployment/recovery, etc. The problem with the present day yachting community is that it is inventory oriented, rather than engineering oriented. Drogue usage(this includes parachute anchors) is an engineering problem. But people seem to want to be able to go into a store and buy a drogue off the shelf, ready to go, as if it were just another bag of stuff to throw in a locker. Now, Don Jordan's comments. Notice the easy to read part about the bow being a poor deployment location, with which I never intended to be taken seriously. But, Don makes the point with which I am inclined to believe is correct that stern damage is a low risk. So, how are we to evaluate this assertion of low risk? Recall that the Jordan design strategy expects the boat to be accelerated as a wave comes along. If the wave is none life threatening then the stresses on the gear are minimal, the boat is pushed around a bit and the wave pass by. If the boat reaches near wave speed during such a pass, but even if some water is splashing around the effects of striking the boat will be minimal as the water speed and boat speed will be near the same. However, if a real monster comes along which threatens to roll the boat or pitchpole it, the Jordan will allow enough acceleration to keep the boat speed and the wave speed close coupled, but prevent catastrophic acceleration. If you can design a better "mousetrap", then use it! And if you can't then I submit that the Jordan Series Drogue is at present the best alternative. By the way, I have a lot of experience with large following breaking waves, some in high winds, and although I have not used the Jordan, I have a high level of confidence that at the moment of possibly being thrown out of control, the Jordan would perform as claimed. If I had to take a chance on the boat taking damage on the stern, versus being rolled or violently pitchpoled, I think I would go for the stern damage. Now, I understand the misgivings that many people have about exposing their stern to large boarding seas. I have the same nervousness. So, here is my take on the problem. Long period waves are very high speed, but the longer the period the less steep they tend to be. A wave that is very steep and near to breaking, even in the open ocean in deep water, is not moving at near the speed of the underlying swell. It is by definition a wave out of character with the general run of waves. Therefore, it is not nearly as fast, perhaps no more than 20 knots, perhaps as little as 15 knots. Now this is more than fast enough, if tall and steep enough to do real damage. But, if you are running with and have some speed up, then any approaching wave does not have accelerate your boat near as much to reduce the difference in speed between the boat and itself. You are after two things here, to reduce the difference in speed and prevent the boat from being flung out of control This difference in speed can't be expected to prevent any and all stern damage, but you might be pleasantly surprised to see what a huge effect it does have. It will be a couple of weeks before I will be back to continue with this subject. After tonight you are on your own. Don is being sent a copy of this. It's too bad he isn't up to writing extensively about all this. Regards, Mike Capt. Mike Maurice Tualatin(Portland), Oregon
DC
Dave Cooper
Mon, Apr 10, 2006 12:33 AM

G'day all, I do agree with Don and his rational for the use of the drogue.
The only downside that I see to the series or "Jordan" Drogue is that you
need sea room to operate in. A 10-12 hour period of running at 5 to 10 kts
would eat up lots of distance towards a lee shore.

I don't know the answer to this issue but closing on a shore will cause the
seas to become bigger and faster as they feel the bottom. Not a good
situation for the left coasters, IMO.

Then again you know my experience with the sea anchor and a bit of nasty
weather. Again better to do everything in your kit to practice weather
avoidance than to have to wrestle with either of these options.

Cheers

Dave
Swan Song
Roughwater 58
Tortola, BVI

G'day all, I do agree with Don and his rational for the use of the drogue. The only downside that I see to the series or "Jordan" Drogue is that you need sea room to operate in. A 10-12 hour period of running at 5 to 10 kts would eat up lots of distance towards a lee shore. I don't know the answer to this issue but closing on a shore will cause the seas to become bigger and faster as they feel the bottom. Not a good situation for the left coasters, IMO. Then again you know my experience with the sea anchor and a bit of nasty weather. Again better to do everything in your kit to practice weather avoidance than to have to wrestle with either of these options. Cheers Dave Swan Song Roughwater 58 Tortola, BVI