Oceanbrake

series drogue

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Don Jordan

Series Drogue, the ultimate survival device for ocean sailors.

Following the disastrous 1979 Fastnet Race, when 24 boats sank or were abandoned and 15 lives lost, American Donald Jordan came up with the idea. A drag device that would revolutionise safety at sea in severe weather, the series drogue.

Jordan had enjoyed a highly successful career as an aeronautical engineer and senior instructor at the Massachusetts Institute of Technology when he used his skills to design a device that would transform safety at sea in dangerous weather conditions.

Jordan carried out thorough testing of his design with full support from the US Coast Guard, culminating in real life testing by USCG lifeboats at the Columbia River Bar. The USCG report CG-D-20-87 can be viewed here.

A Series Drogue consists of 100 plus small cones on a tapering rope measuring anything from 240 feet (73 metres) to 370 feet (113 metres). The specification of the drogue is controlled by the displacement of the boat.

The Series Drogue has an unblemished record for reliability over a quarter of a century. Aeronatical engineer Don Jordan's concept of it being like an ejector seat - pull the cord and sit back, has created the only drag device that requires almost no tending once deployed. Unlike parachute anchors which need constant adjustment and supervision, a sailor setting a Series Drogue can go below and survive the storm in relative safety, rather than risking their life on deck !

If you wish to remind yourself of the power and unforgiving nature of breaking waves or how to install cones, please view some of these youtube clips. including a video of a capsize test by Yachting Monthly.

RECENT EVENTS ......The catamaran "Be Good Too" was abandoned 300 miles east of Cape Henry (United States East Coast) in early January 2014. The primary reason was severe damage to her 2 rudders when she was thrown backwards by a rogue wave. Without going into the many aspects behind the decision to abandon a catamaran that was less than 2 months old, the incident highlights the dangers faced by mono and multi-hulls when hit by a breaking or large wave. In reverse, the loads on the rudder stock and steering gear are greatly increased way beyond anything normal in turning the boat. Water pressure tries to swing the rudder broadside with increasing force. Rudders are designed to be trailed. Most of us will have felt the excessive steering loads that occur when going astern and perhaps have had the wheel or tiller jerked out of our hands, bringing the rudder up hard against the stops with a sudden impact. Lying to a parachute anchor set from the bow has identical risk of being thrown backwards and suffering rudder failure. In contrast a series drogue set from the stern and moving the boat slowly forwards through the water does not carry this danger.

Attainable Adventure Cruising is a highly recommended site jam-packed with valuable information for cruising sailors. Read about a real world series drogue deployment by Paul Kirby, who built his own drogue using Oceanbrake cones. In 80 knots winds and after two knockdowns, Paul deployed his series drogue.

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deployment/storage bag

cone

loaded bag rolled

As one sailor commented after enduring extreme conditions "the Series Drogue is an un-complicated boat saver that works every time". The string of cones ensures that at any moment the vast majority are filled and grabbing the ocean, resulting in the boat remaining perfectly positioned for the next wave strike. The Series Drogue is the only effective capsize prevention measure against breaking waves. Lying stern to the weather is vastly prefererable in extreme conditions and allows the boat to run with the wind and waves in a controlled manner, lessening the speed of the on rushing walls of water. With greater buoyancy in the stern, the majority of the keel leading and the mast and rigging acting like the feathers on the arrow and weathercocking the boat, it all makes logical sense. The Series Drogue with its continuous steady grip, applies a constant pressure on the boat's fittings, resulting in no damage. In simulated fatigue testing, the drogue was subjected to 15,000 cycles (the equivalent of a mighty hurricane) without failure. The drogue looked new and unworn after this experience with only reduced cloth stiffness.

Retrieval of a Series Drogue is straightforward. In most cases it can be done hand over hand when the wind abates. Winches can be used to aid this process in difficult conditions and either by using two 'helper' lines or by winding the drogue around the winch, the drogue can be recovered.

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