At first glance, the IFS Multi Tradewind is a normal furling sail. In principle, it consists of two code zeros or very flat cut gennakers that lie on top of each other. When unfurling from the centre furling system, both halves of the sail unfurl simultaneously - one to starboard, one to port. The result: a symmetrical downwind sail that works like a spinnaker but is much more stable.
The difference to the classic spinnaker lies in the central fixation. While a spinnaker is only held at the head, backhaul and sheet and therefore has a lot of freedom of movement, the Multi Tradewind from OneSails is fixed over the entire length of the furling system. This makes the sail much smoother and prevents the typical wobbling and flapping of a spinnaker.
M-shaped profile for stability
With the Multi Tradewind, the sheets are guided in the same way as with a spinnaker or gennaker. The difference is that they are furled quite far. This creates a characteristic M-shape when you look into the sail from below: Both sails curve forwards between the clew and furling system. This geometry is crucial for the stability of the sail.
The range of use is around 180 degrees wind angle, plus minus 30 degrees. This means that the sail from OneSails works in a range of around 60 degrees - from very rough courses to a direct downwind course. And without active trimming. Once set, the sheets are actually no longer touched.
Trim: Easier than with a spinnaker
When changing course, the sheets have to be guided a little, but the effort is manageable. If you are going to windward, you should feather the sheet a little on the windward side, while bringing the sheet closer on the leeward side. In this way, you turn the entire sail with you, so to speak, and keep it aligned with the wind. At first it doesn't seem intuitive to furl the windward side. If you windward too far, the leech can collapse slightly upwind, but the sail as a whole remains very stable. And even if it falls in a little when the angle is too acute, nothing flutters or catches. No choas like a botched spinnaker manoeuvre.
Even if the sail wobbles back and forth a little, it remains extremely stable - much more stable than a classic spinnaker. This is precisely the great advantage for long-distance sailors: the sail hardly needs any attention. You don't have to constantly work on the trim or intervene in every gust. The Multi Tradewind stands still and generates propulsion.
Designed for passages - the name says it all
The name "Tradewind" - English for trade wind - reveals the target group and the intended use. This sail has been developed for long downwind passages, for ocean crossings in the trade wind zones, for days on end with a steady wind from astern. This is precisely where a spinnaker becomes a constant burden for the crew, and this is where the Multi Tradewind should show its strengths.
You unroll it, trim it once, and that's it. For hours, for days. The crew can devote themselves to other things, sleep, cook, navigate. The sail works reliably in the background. This is a huge advantage for shorthanded crews.
However, the test showed that it can also have advantages on shorter journeys. Especially with little crew or children on board, the easy handling can make all the difference.
Bergen: Remove pressure and roll up
Recovery is very simple, another big advantage over the spinnaker. Both sheets are furled very wide, which takes the pressure off the sail. The Multi Tradewind opens slightly in the leech, but does not flutter, and then you can simply furl it with the furling system. No struggle with a collapsing spinnaker, no risk of an hourglass effect, no hectic furling when the wind picks up.
Even inexperienced crew members can easily hoist the Multi Tradewind. This makes the sail ideal for family crews or mixed crews with different levels of sailing experience.
Can also be used for sharper courses
Interestingly, you can also sail the Multi Tradewind on more acute courses - but with a different configuration. In this case, you sail both halves of the gennaker lying on top of each other, i.e. as a double-layered sail on one side.
To do this, the sheet must be changed once: The sheet that would be downwind is cut off. The actual working sheet is then fed through both clews so that the pressure is evenly distributed over both halves of the sail. This is a little more complicated than normal use downwind, but should significantly extend the sail's range of use.
IFS - Integrated Furling Structure from OneSails
A technical highlight is the IFS system that gives the sail its name. IFS stands for "Integrated Furling Structure". Special fibres are incorporated into the luff of the sail, which absorb the loads and torque during furling.
The big plus: you don't need a heavy anti-torsion cable. With conventional furling gennakers, such a cable is necessary to transfer the force of the furling system to the top swivel. The IFS system from OneSails takes over this function through the integrated fibres. This saves weight and makes the sail much easier to handle.
The technology is not new, OneSails uses a similar system for "cableless furling" for gennakers. But the application on the Multi Tradewind is consistent and works perfectly.
Material: nylon for elasticity
The sailcloth is made of nylon - the classic material for downwind sails. Nylon is elastic, robust and light. It stretches under load, which is desirable in a downwind sail for a cruising boat because it compensates for the typical load changes caused by swell and changing wind speeds.
The flat cut of the two halves of the gennaker is relativised by the M-shape during use. Then there is quite a lot of belly in the sail. The flat cut makes furling easier.
Who is the Multi Tradewind from OneSails suitable for?
The OneSails IFS Multi Tradewind is clearly aimed at cruising sailors who cover long distances downwind. But it doesn't have to be an ocean passage, the sail also works great in local waters.
Installation and equipment
For the Multi Tradewind you need:
- One Rolling system at the bow, positioned in the centre
- Two sheeting points relatively far aft (much further than for genoa or jib)
- Corresponding Pods with sufficient length
- Optional: Barberholer for finer trimming of the sheet angles
The furling system should be designed for the sail area and the expected loads. OneSails provides appropriate recommendations as to which roller systems are suitable.
More on the topic
Michael Rinck
Redakteur Test & Technik
