|Parachute Sea Anchors, Drogues, Sea anchors - What's the difference? |
There is a difference and it is impossible for one to do the other's job. In simple terms a 9ft diameter or larger parachute sea anchor is required to hold a bow head to wind, whereas a 3ft diameter (drogue) simply does not have the power and would allow the yacht to fall backwards or be thrown by a wave. The 3ft Para-Drogue, deployed astern, is designed to slow a boat allowing directional stability downwind. The parachute sea anchor complements the Para-Drogue and vice versa. Traditional sea anchors (Admiralty cone, windsock type) are an item that time has overtaken and today should be renamed to fit into the drogue family. A drogue does not have the power and cannot develop the power to hold the bow of an ocean-going vessel head to wind in any condition.
Ideally a drogue can be used as a means of allowing the safe deployment of a Para-Anchor by substantially slowing a vessel down when it is impossible to heave to or luff up owing to sea state. In this situation the downwind speed of the vessel is substantially reduced and the Para-Anchor can be deployed over the windward side from the cockpit.
Size is important.
As with conventional anchoring the size of anchor is important. Under stress a boat will drag an undersized anchor and lay beam on to the weather. Marginally oversized is fine, as it gives an additional level of security. Substantially oversized and it is a weight penalty and a waste of money. When anchoring to a parachute sea anchor, the same arguments apply. It is therefore important to have a parachute sea anchor large enough to hold bow on in all conditions. As a guide, refer to size chart on following page.
Para-Anchors Australia manufactures parachute sea anchors to an exacting standard of quality with every stage of construction checked and acknowledged.
The Para-Anchor is manufactured from high density nylon, brightly coloured for safety in an air search.
Each radial seam is over-sewn with polyester webbing to absorb the high loads.
All localised stress points in the canopy are further reinforced with vinyl and webbing inserts.
The double braid shroud lines are secured to the Para-Anchor through stainless steel eyelets to the base of the swivel, which is unique in design offering a very compact, strong and effective unit.
Attached at the apex of the canopy is a small segment of stainless steel chain. This, combined with the retrieval system, allows for a very efficient and safe method of deployment.
The self-deploying bag is permanently attached to the back of the swivel allowing for easy deployment.
There are many occasions when boats at sea require repairs to be carried out. Having the bows to the seas, especially if mast climbing is involved, is a major advantage. Even the amount of pitching is reduced, let alone the rolling. When laying to a Para-Anchor any rescue attempt by helicopter or rescue vessel is much safer because the boat is very predictable in its behaviour and capable of being approached from down wind. Single-handers find parachute sea anchors are worth their weight in gold. The degree of self-sufficiency is multiplied many times.
It is extremely important to use nylon for the rode (either 3 strand or braided) with a minimum of around 120 metres. On multi-hulls, bridle and rode lines should total approximately 120 metres (100 m rode and 20 m bridle arms). Typically, nylon has a stretch factor of approximately 30% when wet (50% dry), thus extending your rode to about 150m. Because of the stretchiness, about 25% of the load will be captured by the rode itself. The longer the rode, the less the strain on the boat and the parachute sea anchor. Rode diameter and length is very important to achieve the maximum comfort and safety from the Para-Anchor system. Too large a diameter and the stretch of the line is reduced. At the same time too small a diameter of line and the elasticity in the line is reduced by the fact that the rode line is stretched to its maximum too much of the time. If the diameter is too small the risk of a rode line breaking is very much a possibility. It is often said that the rode line length should be x times length of boat or y times height of waves, etc. It is an impossible task to adjust the rode length in the conditions that are applicable at the time of use. Who wants to be on the foredeck adjusting the length of the rode line at 0200 hrs, with minimal crew as backup in 50 knots. An impossible task. At some time in the past we have all towed a motor vehicle. Had we towed that car with an excessive amount of towline it would have been impossible to control the tension in the line. The towline would have spent most of its time dragging on the road with a risk of the towed car fouling the line. With a rode line that cannot develop the correct level of elasticity (shock absorption) because of incorrect diameter or length, the boat secured to the Para-Anchor will misbehave badly, surging forward, backing down and veering around.
There is more than one way to skin a cat. There are more ways than one of deploying a parachute sea anchor, but a simple, safe and effective method is to rig the system prior to departure. Secure the rode line from the bow outside of the lifelines fastened to the toe rails or stanchion bases by plastic cable ties, and lead it to the cockpit where it is made secure to the nearest stanchion base. When the parachute sea anchor is required, shackle all lines to the appropriate parts and deploy the retrieval floats over the windward side followed by the Para-Anchor in its self-deploying bag. Allow Para-Anchor to inflate with the water. Once inflated and all lines have deployed and the boat is stable, check for security and eliminate chafe. Now set up a regular radio and anchor watch and then go below and enjoy the ride.
Tightly packed in a series of linked cells, Tasman 15 parachute sea anchor, float and retrieval system. The operation of this unit is simple and straightforward. Once received by the vessel in distress, the nylon rode tail is removed from under the restraining flap and clipped to a strong point on the bow of the boat. The complete package is then thrown into the ocean while at the same time tearing open the yellow velcro retaining strap. The parachute sea anchor will now deploy from the container, pull out 100 metres of line, stabilise and hold the bow of the vessel head to wind.