Sea anchors and drogues, one voyager's experience
Aug 16, 2007
To the editor: In Lin and Larry Pardey’s Storm Tactics Handbook the Pardeys recommend setting a sea anchor from a bridle (see also Peter Bruce’s edition of Heavy Weather Sailing, 5th Ed.). This approach is questioned by our experience in our Nicholson 35 Moonlight of Down. We accept that the Pardeys’ use of a 9-foot mesh drogue (a medium drag device) on their full keel yacht worked for them; the whole system trawled through the water in a dynamic mode leaving a slick to windward. However, we found that the same tactic is not suitable for use on a fin and skeg yacht like a Nic 35 using a conventional 15-foot sea anchor (a high drag device).
For example, en route from Newport to Bermuda Moonlight of Down encountered force eight, forecast to rise to force 10, and we deployed a 15-foot diameter sea anchor. The anchor was set with a bridle as the Pardeys prescribe, with the boat hove to on 400 feet of 5/8-inch octoplait nylon rode (giving roughly 30-percent stretch) and 33 feet of chain for added catenary. The sea anchor was so powerful that it caused the boat to tack onto the bridle. After the third time having the boat become very vulnerable lying on the bridle, we abandoned the bridle and lay conventionally under bare poles head to wind with the sea anchor deployed. In the gusts the rode extended to its fully stretched extent as the holding power of the anchor was so effective.
By dawn the gale had passed and the wind was down to force four. We found that the rode had lifted out of the bow roller due to the elevation of the rode by the oncoming swells. One needs to arrange a substantive captive device to guard against this. The sea anchor was easily recovered by slowly motoring upwind along the line of the rode until the pick-up buoy was reached; the sea anchor was then brought aboard like a deflated balloon. We then hove-to for some sleep before proceeding.
We hove-to our Nic 35 quite a lot when the sea conditions were too rough to make progress on the ocean while close-hauled. This occurs at around force seven when the off-duty watch keeper gets regularly bounced in the bunk and cannot sleep. We found the hove-to best under triple-reefed main only in force seven or trysail only (carried on deck loaded into its separate track, bagged with its outhaul/downhaul fitted) in force eight. We found it best to outhaul/downhaul the clew to the main boom end rather than sheet it to the quarters, as the flogging sheets as you hoist the sail in force eight are highly dangerous and likely to inflict serious head injury to anyone in the cockpit. Any attempt to set a backed storm jib will result in the boat lying beam on (again a function of the keel/CLR being so far aft) a potentially dangerous situation.
We had a contrasting experience in the Indian Ocean. Running before reinforced SE trades, a constant force eight, under storm jib the seas became threatening for a time as a depression in the westerlies to the south passed by. The boat showed a tendency to broach as it slid down the face of the 16-foot swells coming up on its quarter. If one had broken it might well have broached. We deployed a 36-inch drogue on 16-foot-by-3/8-inch chain (25 pounds) and 325 feet of 5/8 octoplait (65 held in reserve for freshening the nip, etc). The effect was dramatic — the speed dropped from 6 knots to 3.5 knots and the yacht steadied right up and continued on its course under control of the Hydrovane. We towed from the windward primary winch through a cross over fairlead on the taffrail aft. The oncoming swells would occasionally lift the rode from the fairlead, but we managed to lash the anti-chafe tube into the fairlead. We later fitted closed (Panama) fairleads to the taffrail.
We had a bridling rope ready to use from the lee quarter but found it was not necessary.
The following day we could see the drogue being disturbed by cross seas in the swell three hundred feet or so astern (the water was crystal clear). We later learned from reading the Wolfson report (produced as a result of Fastnet 79) that the weight ahead of the drogue should be 50 pounds, and we now have 33 feet of 3/8-inch chain ready if required.
Recovering the drogue when the seas settled (still blowing force seven to eight) was somewhat difficult. Trying to grind the rode in on the primary winch was causing an unreasonable heart load. So we had a cup of tea and thought about it. Bringing the rode to the bow and motoring upwind was a bit too daunting so we rigged a snatch block to a chain plate to lead the rode to the electric windlass and powered it in with the engine running to charge.