Sail handling: Downwind cruising made easy

May 15, 2017 General Interest ,Technology

If you’re tired of tweaking finicky spinnakers and gennakers – and then wrestling them into submission when the wind picks up – you should consider the Simbo Rig. Words and images by Iain Simpson.

110531 570-017 075_cmyk (Small)The Simbo Rig is a sail management system which involves flying identical 106 percent twin jibs with a high-cut clew. It enables short-handed crews to sail efficiently on all points of the wind with minimum foredeck work, controlled from the security of the cockpit.

Simbo Rig is an acronym for Simple Bow Rig. It’s been developed over 65 years of cruising which includes six trans-Atlantic crossings and the Mediterranean. It’s ideal for short-handed cruising sailors who, these days, are not only handling larger and more powerful yachts but also tackling longer passages often involving weeks at sea.

The rig enables a short-handed yacht crew to sail efficiently and safely dead downwind without resorting to coloured sails. And unlike spinnakers and gennakers, it’s a working rig – it’s easy to make an immediate course correction to avoid collision or turn up to weather to retrieve a MOB. This single suit of sails is permanently rigged to meet your needs no matter whether hard on the wind, bearing off to a reach or running dead downwind.

DSC04842 (1)_cmyk (Small)Apart from the raising and stowing of the whisker poles, no further foredeck work is required and with in-mast mainsail and jib furling, one person can control the rig from the security of the cockpit without calling upon off-watch crew. Assuming, of course, the yacht’s under the control of a reliable auto-pilot.

The two identical jibs are hoisted up the twin grooves of a furling forestay on a single halyard. The sails always fly together with no appreciable additional wear over a solo jib. My jibs and in-mast furling mainsail were made in Dimension-Polyant’s Hydranet woven cloth – a hybrid of woven polyester with a Spectra rip-stop.

On the wind – the twin jibs enable you to rest one sail on the other to re-run the sheet from the clew, to inside the cap shroud for a tighter sheeting angle; in the same way you can also adjust the sheet car up the track without, in either case, incurring flogging sails or loss of boat speed.

On tacking – one releases the upwind leeward jib to rest on its downwind twin, to leave just the remaining sheet to be freed on coming through the wind. Once through, the new downwind jib/sheet captures its upwind partner and trimmed to the new course, the upwind jib sheet then takes over final tweaking.

On reefing or striking the jibs – the twin sails furl together around the forestay. As both sails have their own set of sheets there is of course, double the quantity in the cockpit but this can be simplified by their being colour-coded.

The Simbo Rig really comes into its own when the yacht bears away to a run.

The twin jibs separate to their respective sides of the yacht to create a powerful cloud of sail. I’ve found that, with the mainsail eased to 45o off centre, the following wind continues on around the mast into the windward jib. The accumulated wind is redirected into the leeward jib which would otherwise be blanketed by the mainsail. To gybe, simply haul and release the mainsheet onto the new tack leaving the whisker poles and jib sheets unaltered.

Before bearing off to a run from a reach, raise the weather whisker pole on its boom-lift, with the attached fore-and-aft guys and the weather side’s lazy sheets run under the whisker pole’s retractable bolt. This enables the twin jibs to be separated immediately on bearing away.

If remaining on that tack there is no need to hoist the leeward whisker pole as it is the redirected wind that sets the sail. On subsequently requiring to gybe, the leeward whisker pole can be set without loss of drive by restraining the sail by its weather sheet whilst rigging the pole following which the sail’s retention can be transferred back to the poled out leeward sheet.

A more relaxed approach to setting up the whisker poles is to furl away the jibs on bearing off to a run, rig the poles and then unfurl the jibs to their respective side. However, if running dead downwind i.e. with the true wind no more than 10o off the stern, the twin jibs will set without the whisker poles by running the sheet cars forward to tighten down the sails’ leech to cup the jibs.

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Unlike running with coloured sails, the twin jibs can be reefed underway by furling the sails from their respective sides around the foil. Furthermore, if hit by an unexpected squall, you can immediately dump 50 percent of the sail area by coming onto a reach and allowing the backed weather jib to fly to leeward. The whisker poles can be retained on a reach until the apparent wind is 60o off the bow when the leeward sheets are released from the W/P claw and the poles stowed.

In my opinion, coloured sails have no place on a short-handed cruising yacht other than as a piece of fun in sheltered water and settled weather. The Simbo Rig can comfortably be retained albeit reefed, right up to full gale force without anxiety or challenge.

Sailing between the Azores and England, I was caught out by a 50-knot squall under full mainsail and jibs. The yacht lifted onto a plane and continued sailing dead downwind without hint of rounding up or course wandering – at 15.5 knots SOG. I have used the rig on all three yachts I’ve owned over the last 15 years – a Najad 460, 511 and my current 570 – experiencing several gales with total confidence and complete control.

For yachts with no forward lowers, the whisker poles can be jointly stowed up a forward-mounted mast track and lowered like wings to pre-marked settings on their boom lifts. Fore and aft guys ensure that the poles are at the correct angle to the yacht and mast.

With yachts like the Najad 570, the whisker poles are manually stowed up the mast and subsequently rigged between the fore and aft lowers by attaching the inboard end to the hinged male mast fitting. Carbon whisker poles are lighter and easier.

The video shows the twin jibs being unfurled to their respective whisker poles in 10 knots of wind. Note the immediate acceleration in the yacht’s speed once the sails have set. As there is no significant pressure from the leeward pole and the main boom only opposes the weather pole at 45o, downwind roll is reduced to a minimum.

For more information on the Simbo Rig visit