Drogues and drag devices
Sailing downwind in rough conditions can be very uncomfortable; sometimes even dangerous. A simple drag device can often tame the situation, bringing added safety and making your boat easier to control.
It’s not often you need some form of drogue but when you do it can transform your life. The photo that heads this article shows us running more of less downwind some 70 miles off the north-west coast of Africa, en route for the Canary Islands. The wind was more or less dead astern, a gusty 30 knots or so – awkward but by no means dangerous.
Indeed, conditions would have been perfect had it not been for an awkward cross swell that rolled in from the starboard quarter, slewing the stern to port and gybing the half roller-reefed headsail – the only sail we had set. It was time to tame such irritating behaviour by deploying our simplest drag device, a 100m (109yds) bight of 18mm diameter eight-plait polyester rope.
The photo at the head of this article shows the bight deployed. It’s no more than simple loop, with each end attached to the port and starboard mooring cleats and streaming nearly 50m astern. It took no more than ten minutes to dig it out of a locker and rig, whereupon its effect was instantaneous. The slewing abated, crew comfort improved, the autopilot became less desperate in its efforts – all without any perceptible reduction in speed. In fact, with the headsail now drawing more constantly, we might even have gained a fraction of a knot or so.
A few hours later, the weather had eased and we were able to retrieve the bight simply by releasing one end and pulling it in.
That simple bight had been sufficient in those relatively moderate conditions. Had wind strength and wave action been more severe we would have dug out the Galerider drogue and streamed it astern at the end of that same length of rope.
In these circumstances it’s important to try and place the drogue at the rear of the next following wave as shown in the illustration below. This gives it a solid body of water to pull into.
Often known as ‘Jordan Series Drogues’. Never having tried these in anger, I must rely on hearsay and written reports, but the principle looks sound. Instead of a single large drogue, a series of tiny fabric ones are attached along the length of an end-weighted line. Clearly with this arrangement the positioning of the drogues in relation to the wave frequency is less critical. You simply stream the whole length astern and it takes care of itself without further adjustment.
Reports as to their efficacy are generally favourable but I see the potential for tangles as being high. Since we’re entirely satisfied with our existing arrangement I see no reason to change. I strongly believe that any sailboat proceeding offshore should at least carry a length (as long as is practicable) of heavy line with which to form a bight. Such a line would have many other uses than described here but even its role as a simple drogue is more than enough reason to do so.
It’s tempting to group sea anchors with drogues but they really don’t belong together because they perform entirely different functions. Whereas drogues are intended to help control the downwind progress of a sailboat, the purpose of sea anchors is to hold a boat as near stationary as is practical – as if ‘at anchor’ though of course in impossibly deep water.
A typical sea anchor resembles a parachute – indeed many are adapted from military style cargo chutes normally used for dropping supplies. They are invariably streamed from the bow, either holding a boat head to wind or at a slight angle. Some offshore sailors prefer that latter technique, claiming that the slick caused by the inevitable slow downwind drift helps suppress the waves. I suspect the choice might depend of the vessel’s displacement with lighter boats prospering better under the first option while heavier ones might go for the latter.
So far, I’ve yet to do either so have no basis to judge. If any readers have any further information, I would very much like to hear from them!