How to Specify a Jimmy Green Yacht Drogue System

How to Specify a Yacht Drogue System for Your Yacht

What is a Yacht Drogue? 

A yacht drogue is a cone-shaped sea anchor designed to deploy from the stern to slow a yacht’s speed downwind in severe weather conditions. It is a type of sea anchor, a term which covers various means of stopping or slowing a yacht without engaging with the seabed. To differentiate, Parachute Anchors are generally deployed from the bow to hold the boat head to wind and reduce its sternway to almost, but not quite, a stop. 

How is a Yacht Drogue Deployed? 

A Yacht Drogue should be towed a good distance behind the yacht using a long anchor rode, ideally attached to the stern via a V-Bridle. 

What are the Benefits of a Yacht Drogue? 

• Slowing a yacht’s speed to afford more steering control
• Keeping the boat tracking downwind and down the seas
• Helping to avoid broaching in surf conditions
• Reducing the wind speed and spray across the deck compared with lying to a parachute anchor upwind
• Reducing the risk of breaking seas compared with taking the storm bow on
• Reassuring the crew with a safer, more comfortable ride

Where and when may a Yacht Drogue be Required?  

Principally, a yacht drogue system may be necessary during severe weather while sailing offshore waters, particularly Transocean, where the long fetch can result in towering, breaking seas. The concept of running before the storm in a controlled manner naturally means that extensive searoom will be required. 

The World Cruising Club, organisers of the Atlantic and World Rally, recommend a yacht drogue set up as part of the safety equipment inventory for participating yachts. Their safety requirements are also a good source of information for yacht owners and skippers planning an independent extended cruise. Their mandatory requirements and recommendations are freely available online: 

World Cruising Club Safety Equipment Requirements 

Do I Need a Yacht Drogue? 

Of course, that’s a difficult question because it depends on how severe the weather will likely be for your voyage. Modern-day onboard communications linked to specialist weather data can make departure and course setting a much more scientific decision, but the risk of extreme weather is reduced, not eradicated. And if you have entered a rally or race, you will have lost some control over passage planning.  

It is quite possible that you won’t be able to afford every piece of safety gear recommended, and the space and load capacity of the yacht will be limited. But knowing you have a crucial tool for extreme-weather survival on board can provide much peace of mind. It’s like an insurance policy: you hope you will never need it, but it’s good to know it’s there in an emergency.

Alternative Measures 

If you decide against a yacht drogue, preparing a plan of action for coping without one in a worst-case scenario will be essential. Read as much as possible about yacht owners' experiences and how they managed. At the very least, consider a long warp as a necessary part of your inventory and earmark something on board which would be suitable to tow as an emergency brake.

What are the Main Constituent Parts of a Yacht Drogue System? 

1. Spliced V Bridle for attachment to the stern mooring cleats
   
   
2. Load-rated Joining Shackle from Bridle to Warp
   
   
3. Anchorplait Anchor Warp
   
   
4. Short length of Anchor Chain (as a weight to keep the drogue in the water)
   
   
5. Load-rated Joining Shackles for a) Warp to Chain, b) Chain to Drogue, or c) Chain to Swivel and d) Swivel to Drogue – c) and d) may not be required for a swivel with clevis pin ends 
   
   
6. Load-rated Swivel, Optional
   
   
7. Yacht Drogue

Why is a V-Bridle recommended in a Yacht Drogue System? 

A V-Bridle should take advantage of the stern mooring cleats - or be mounted on specially fitted heavy-duty eyes on the quarter or transom – to share the shock load. 

A V-Bridle can also help adjust the steering angle to the following sea pattern when the wind and wave direction are offset. 

Yacht Drogue, Warp and Components: Strength and Sizing Considerations 

Calculating how strong the equipment needs to be is complex. 

The Load on the Drogue 

The strain will depend on the initial yacht's speed and the braking force applied. There is the potential for significant shock loading if the rode comes suddenly taut due to the wave action. 

Warp Sizing: Selecting your Rope Diameter 

A good starting point is the appropriate anchor rope diameter according to the yacht length and displacement: 

Establish your Yacht Drogue Rode Size. 

1. Find the column below that best represents your Boat Length Overall. 
   
   
2. Compare your displacement with the tonnage listed. 
   
   
3. If the displacement is greater than displayed in your column in the table, or the yacht is a multihull, consider moving across to the next column to increase the diameter. 
   
   
4. Consider how much braking power you intend to apply in the worst-case scenario for deploying your Yacht Drogue.
   
   
5. Remember that your yacht may not be conveniently in the middle of a column. You may need to interpolate based on how close it is to the next column. 

N.B. This table is a guide with columns based on the following: 

Top Quality Grade 40 Anchor Chain 

Top Quality LIROS Rope 

LIROS recommendation 

Jimmy Green's experience and customer feedback 

Yacht Drogue V-Bridle Sizing 

The V-Bridle should generally be the same diameter as the warp.

Yacht Drogue Chain Sizing 

Select the compatible chain size from the Benchmark Guide. 

Manufacturer Load Rated Shackles Sizing - and Swivel if required  

A Yacht Drogue System will only be as strong as the weakest link, so ensuring that all the components have reasonably similar manufacturer break loads is essential. 

You can check the relative break loads of the drogue warp, the bridle and the chain online: 

Mooring and Anchoring Ropes Break Load Chart 

Calibrated Anchor Chain Break Load Chart 

Here is a quickfire compatibility guide followed by some basic principles: 

Pick shackles with a comparable break load to the warp and chain. 

This will typically entail opting for the maximum shackle pin diameter that will fit through the last link of the chain. 

Bow shackles provide better articulation than D shackles.

Shackles with a published manufacturer breaking load are recommended for critical applications. 

Stainless Steel shackles

Jimmy Green Yacht Drogue Sizing 

Jimmy Green Yacht Drogues are sized approximately according to yacht length in bands of two metres. 

This doesn’t take into account i) displacement, ii) windage, iii) desired deceleration performance.

Jimmy Green Yacht Drogues 

Will a Swivel be Required in a Yacht Drogue System? 

Opinions can be divided on whether or not a swivel should be included. 

We advise practising deployment if at all feasible. You can try towing the Yacht Drogue System without a swivel and see if it performs for your yacht setup. It will be a simple enough task to add a swivel if required: 

Wichard Forged HR Swivels 

APL Stainless Steel Swivels 

Practical Boat Owner magazine carried out some rudimentary ‘trawling’ tests under power back in 2014, and the Jimmy Green Yacht Drogue didn’t spin, slew or porpoise when deployed without a swivel in the system.

This may have been because the balanced eight-strand Anchorplait rope construction absorbs any twist until the resistance in the lay eventually subdues any inclination to spin.  

Please note that the drogue warp should only be Anchorplait, definitely not three-strand, because of the twisting implications, with or without a swivel included. 

Determining the Optimum Length for a Yacht Drogue Warp and Chain 

The main principles are: 

• As long a warp as practicable – generally 80, 100 or 120 metres. The length helps to maintain the yacht’s tracking and prevent broaching by keeping the yacht drogue submerged in a wave as far behind the yacht as possible. 

• A short length of chain comparable with the break load of your bower anchor rode, generally around 5 metres, but just how much weight is required to ensure the right level of submersion will depend on the length of the warp.

Jimmy Green Ready-Spliced Drogue Warp Options: 

80 metres - Jimmy Green Ready-Spliced Yacht Drogue Warps

100 metres - Jimmy Green Ready-Spliced Para Anchor Warps

 Make your Drogue System Components Multi-Purpose  

Pay careful attention to how each part can be versatile to save on budget, space and weight, e.g. 

The warp and the bridle can double up as a towing line 

The warp and chain can also be a secondary (kedge) anchor rode with, e.g. an aluminium anchor, such as the Fortress

The V-Bridle will be ideal for snubbing your main anchor chain with the addition of a suitable hook or grab

Yacht Drogue Specification Checklist 

1. Drogue V-Bridle – same diameter as the Warp
   
   
2. Load-rated Joining Shackle from Bridle to Warp
   
   
3. Drogue Anchor Warp – must be Anchorplait, 80-120 metres, comparable to your Main Anchor Rope
   
   
4. Anchor Chain – short length, comparable to your Main Anchor Chain
   
   
5. Load-Rated Joining Shackles for a) Warp to Chain, b) Chain to Drogue, or c) Chain to Swivel and d) Swivel to Drogue – c) and d) may not be required for a swivel with clevis pin ends
   
   
6. Load-Rated Swivel, Optional
   
   
7. Jimmy Green Yacht Drogue – sized by yacht length in bands of two metres