Jordan Series Drogue experience

[S/V Alchemy]

Originally Posted by mikereed100

Disclaimer: This is an account of a single deployment of a JSD, with conclusions drawn by a troubled mind. As such, it is presented not as dogma, but as a basis for discussion.

And so it is. Thank you for precisely the sort of lucid real-life report one doesn't see often outside of books with titles like "Heavy Weather Survival Storm Tactics AIEEE!!!"

I think the takeaways (given I'm responding before reading the rest of the thread) is that the JSD worked to the point that it preserved vessel and crew, and reduced the forward speed under poles to a rate (4 knots SOG) that the AP could work in conditions in which it usually would not (APs in cruising monos tend to start to react too slowly in winds past 35-40 knots, in my thankfully limited experience). So there's the chance to rest, even though I suspect you were eyeballing the JSD and the waves and the AP pretty intensely.

The argument about shock loading is interesting because of the variables. I see the case for Dyneema to reduce weight for most of the drogue's length, but perhaps with some sort of heavy final nylon length to attach it to the boat's bollards or drogue attachment points. I don't recall if you mentioned special strapping or bollards on your cat designed to take the drogue loads.

The ideas for both increasing the number of cones and beefing them up individually have merit, although I suspect if you added more cones, the subsequent slowing of the boat to the "expected" speeds would obviate the need to reinforce the individual cones...less speed, less wear and fraying. But on the other hand, you probably don't want to experiment overmuch as this single deployment seems to have put a fair bit of wear on your JSD, so a belt and suspenders version in the Mark 2 drogue is pretty compelling.

The pendant trick taken forward to the bow is a good tip. Thanks again for some information anyone in a bad weather scenario can use to their advantage and increase in safety.

[Mike OReilly]

Originally Posted by colemj

A drogue won't keep your bow to the wind unless it is big enough to be a parachute anchor. In which case, it would be a parachute anchor and not a drogue.

For most boats, a drogue off the bow will cause the bow to fall off the wind and sail around on it. You will have potential for waves to do a lot of damage and it would be uncomfortable.

Mark

Thanks Mark. So are you saying the same dragging device (call it whatever want) that will hold the stern to the wind will not be sufficient to hold the bow to wind? The bow will fall off, but not the stern? Hmmmm.... The same input forces are at play (wind & water) ... I suppose the boat will travel forward easier when facing forward (the stern drag arrangement). This would increase the force the drogue puts on the boat ... I guess that's the difference.

I wonder how different hull shapes would react (double ender vs flat stern, for example).

(In case this comes across as being a wise-@ss question, it's not. I'm honestly exploring the questions.)

[Caracal]

Originally Posted by Mike OReilly

Thanks Mark. So are you saying the same dragging device (call it whatever want) that will hold the stern to the wind will not be sufficient to hold the bow to wind? The bow will fall off, but not the stern? Hmmmm.... The same input forces are at play (wind & water) ... I suppose the boat will travel forward easier when facing forward (the stern drag arrangement). This would increase the force the drogue puts on the boat ... I guess that's the difference.

I wonder how different hull shapes would react (double ender vs flat stern, for example).

(In case this comes across as being a wise-@ss question, it's not. I'm honestly exploring the questions.)

While that is all true, you're ignoring the appendages that will be travelling through water, not least of which will be the rudder which will be at the "leading" end when doing that. Also, there is the wind, and since most boats have a mast (and furlers etc) more in front of the midpoint of drag (for want of a better term), those two things in combination will attempt to swing it at least sideways whenever there is the smallest of slack in the line.

[carstenb]

Originally Posted by Caracal

No, you still don't seem to understand it:



If the water is moving faster than the boat, the drogue will be travelling that same speed, minus the drag of the boat. You use the water to slow down against the wind (or practically stop in the case of a sea anchor).

You use the body of water and a drogue or sea anchor , specifically because it does not move (much) compared to the wind and wave action.

I stand corrected. Thank you

[Caracal]

No problem

[JPA Cate]

MikeO'Reilly,

We're about to get out of internet range for the next week or two, so my last post for a while.

If you feel concerned about what Caracal wrote about the rudder trying to turn itself, lash the tiller. FWIW, I think that as long as you are making any way at all, the boat is moving through the water in the normal direction, and the stresses will still be on the normal leading edge of it. You also will notice that you leave a bit of a "slick" behiind you that tends to change where the breaking part of the wave goes. This is why they used to drip oil off astern--the oil on troubled waters--to make it safer for the ship.

Bye now, everybody.

Ann

We're off to Pt. Davey now.

[Caracal]

I wasn't only talking about the rudder trying to turn itself, but rather how that force will try to turn the boat even if it is lashed. It's like throwing an arrow, feathers forward.

[LakeSuperior]

Originally Posted by Mike OReilly

Thanks Mark. So are you saying the same dragging device (call it whatever want) that will hold the stern to the wind will not be sufficient to hold the bow to wind? The bow will fall off, but not the stern? Hmmmm.... The same input forces are at play (wind & water) ... I suppose the boat will travel forward easier when facing forward (the stern drag arrangement). This would increase the force the drogue puts on the boat ... I guess that's the difference.

I wonder how different hull shapes would react (double ender vs flat stern, for example).

(In case this comes across as being a wise-@ss question, it's not. I'm honestly exploring the questions.)

The series drogue is designed to slow the hull to a moderate speed and not stop it. However, faster the hull tries to move the more force exerted by the drogue. Indeed, the series drogue, by design, has substantially less drag than a parachute type drogue that would be deployed off the bow.

If the series drogue is deployed from the bow the bow will tend to fall off as mentioned above because of less drag. In fact, the boat will be moving at a faster average speed in reverse than would be desired. Imagine trying to steer a boat moving in reverse with a rudder in storm conditions as the bow is getting blown down.

However, steering downwind with a drogue deployed from the stern is natural as it is how the boat is designed to operate.

Different tactics are used depending on conditions. One can imagine that the first level of defense is hove to, second may be a parachute off the bow, and finally in extreme storm conditions a series drogue would be deployed off the stern.

Once conditions are extreme with large steep breaking waves the shock loads on a parachute system deployed from the bow and designed to minimize speed also become extreme and can exceed the breaking strength of the line. Additionally, in these conditions the single parachute may pull out of the wave face and cause the hull to accelerate in reverse.

I believe that in extreme storm conditions the series drogue is the only viable means to survival. In more moderate conditions, I think that a series drogue would also work well. Consequently, we had a Jordan Drogue with us and not a parachute.

[robert sailor]

Mike,
One of the advantages of the modern fin keel spade rudder designs is the ability to steer at high speeds and large waves. There is no getting around the steering power of a spade rudder compared to the barn door rudder on your boat. If you decide to run before a storm the problem you will have is steering your boat at higher speeds coming down the waves. Once your boat starts to broach it is very difficult to get it back online because the rudder is not as effective, sooooo! if you should decide to run off you should have some way of slowing your boat down so that you can steer it. Anything including warps will often do the job however the downside to this strategy is that this is a very active strategy and your going to be at the wheel for many hours (been there and done that, not fun) If you are like 90% of the offshore cruising couples then its just you and your better half and for that team you need a passive strategy and the most popular plans are heaving to and or using a series drogue. Either plan means that you can rest below in relative safety and comfort. If you sail the normal safe times of the year then its very unlikely that you'll run into weather that you can't sail in but if it should happen heaving to is an excellent strategy for your boat. You can't run off like a fin keel spade rudder boat in the worst conditions but they can't heave to like you can because they tend to fore reach and never leave a slick like a full keel boat will. I suppose if you have some extra $$$ around as well as room for a SD (they are not light either) and it makes you feel safer then spring for the drogue but if I had your boat I'd probably spend the money on something else.

[HappyMdRSailor]

Undoubtedly one of the best threads and better discussions on CF... Thanks for posting Mike !

[Tantalus]

I will probably regret this but...my 1/2 cent worth.

The assumption that the water in the wave is moving horizontally is wrong. While the wave form is traveling horizontally the water itself is actually moving mostly vertically. Consequentially the boat is lifted on the front of the wave and ends up surfing down it. The drogue slows down that acceleration with the help of the relatively stationary water.

[colemj]

Originally Posted by Mike OReilly

Thanks Mark. So are you saying the same dragging device (call it whatever want) that will hold the stern to the wind will not be sufficient to hold the bow to wind? The bow will fall off, but not the stern? Hmmmm.... The same input forces are at play (wind & water) ... I suppose the boat will travel forward easier when facing forward (the stern drag arrangement). This would increase the force the drogue puts on the boat ... I guess that's the difference.

I wonder how different hull shapes would react (double ender vs flat stern, for example).

(In case this comes across as being a wise-@ss question, it's not. I'm honestly exploring the questions.)

Yes, a drogue doesn't provide sufficient drag to hold the bow to the wind. It doesn't really hold the stern to the wind - it just slows the forward speed of the boat, and most people set it DDW.

I suppose there may be types of boats that have equal attitude stability with the wind in front or aft, but most boats will fall off the wind when it is on the bow and run mostly before the wind if it is on the stern. Many boats go beam-to in either wind direction.

A drogue off the bow will be detrimental to these boats - not even accounting for the forces on the rudders, etc.

Mark

[Mike OReilly]

Thanks everyone, I really appreciate the thoughts and wisdom. Your answers have helped me better understand some of the force dynamics at play. So thanks

To recap, for my style of boat, heaving-to is definitely our first line of defence. Our boat settles beautifully in high winds and large seas. Huge breaking waves would be when I'd want a different tactic. Glad to hear a drogue will be effective, even for my old style of boat.

But as you say Robert, the likelihood of me being in this kind of situation is, well, very unlikely. My limited resources will likely be better spent on improving my hove-to skills, acquiring storm sails, and buying more rum -- for when I've given up and gone down below .

[cburger]

Originally Posted by Mike OReilly

Very informative thread. I've never been close to a survival storm, but am preparing our boat for the big departure this summer. These discussions of storm tactics always leave me wondering how individual boat characteristics factor into optimal choices.

To make it personal, I have a heavy displacement, full keel, barn door, double ender with a vane and windmill hanging off the stern. We sail with two on board. I've been planning to build a series drogue, but this discussion has me wondering whether a drogue is the best choice for my boat. Does some sort of sea anchor make more sense once we approach survival conditions?

And following up on captain58sailin's questions (which seem to have been dismissed out of hand), if the objective is simply to keep the bow into the wind, why couldn't you trail a drogue off the bow? The objective, it seems to me, is not to stop the boat, but to maintain bow-to-wind.

Jordan was convinced that boats were being lost to large breaking waves and the idea is to prevent broaching, pitch poling, being dropped of the top of the wave. The original op's story while very scary doesn't sound like he dealt with large breaking waves in a confused sea state. Under such conditions lying to a drag device off the bow trying to keep the bow to the wind can still allow for you to get hammered by a wave from another direction and hurt severely. Just read Fastnet 10 about the 79' Fastnet race, 15 sailors killed on numerous boats in the conditions of huge confused sea, with high wind speeds. High tech sailing yachts were chucked off waves like toys, while an old wooden Sparkman and Stephens designed full keeled boat sailed around pulling hurt and terrified sailors from stricken vessels.

I haven't read the link to Jordan's work in some time but I seem to recall another idea with his system is you don't just chuck it out there but the length of JDS is adjusted to the wave frequency and slow the boat and get the waves pass under the hull and not on top of you.

Another thing to point out is that the JDS is not conjecture but a proven system tested in the lab on multiple hull forms and wave types and works and saves lives. I believe the claim is no lives lost by any boat using a JSD. If I could only carry one type of drag device on the boat it would be a JSD.

Double enders with hung rudders need special thought to the attachment of the device so you don't do damage the rudder.

[goboatingnow]

Originally Posted by cburger

Jordan was convinced that boats were being lost to large breaking waves and the idea is to prevent broaching, pitch poling, being dropped of the top of the wave. The original op's story while very scary doesn't sound like he dealt with large breaking waves in a confused sea state. Under such conditions lying to a drag device off the bow trying to keep the bow to the wind can still allow for you to get hammered by a wave from another direction and hurt severely. Just read Fastnet 10 about the 79' Fastnet race, 15 sailors killed on numerous boats in the conditions of huge confused sea, with high wind speeds. High tech sailing yachts were chucked off waves like toys, while an old wooden Sparkman and Stephens designed full keeled boat sailed around pulling hurt and terrified sailors from stricken vessels.

Actually I don't think that is an accurate summation of what happened during the 79 fastnet race. Firstly the boats were quite close in shore , with extremely confused seas.

Secondly many were saved by the lifeboats

Few were saved by other boats.

Most of the heavily crewed high tech stuff actually got through the storm. The IOR hull form boats often lightly crewed with very amateur people seemed to get into trouble.

Dave