James Stevens answers your Questions of Seamanship. In this article, with a ripped mainsail would you continue sailing from Kinsale in Ireland to Falmouth on the south coast of Cornwall?

You are sailing in squally conditions when your mainsail rips.

Do you continue on your passage or turn back?

James Stevens looks at the problem and provides the solution.

Question: With a ripped mainsail, would you turn back or carry on?

Jack and Grace are owners of Spartina, a Bavaria 34 fractionally rigged sloop in which they have been enjoying the delights of southern Ireland.

Unfortunately it is now time to head back so they have departed from Kinsale and are heading towards Land’s End and on to Falmouth.

The forecast is not ideal; they have gusty headwinds at first but the wind should veer and settle to about 12 knots soon.

Their course is 135° T which means it will be a close reach to the rocks and strong tides off Cornwall, about 140 miles away.

Spartina is well fitted out for cruising and has a storm jib, a number one genoa, a number two genoa and working jib.

During one of the squalls, the main tears from leech to luff above the reefs.

A chart showing the route from Kinsale to Falmouth

Credit: Maxine Heath

Jack and Grace drop and secure the main but are now sailing under jib alone.

Jack looks anxiously at the fuel gauge; he knew they should have topped up but the fuel dock was shut that morning and they needed to set off.

They only have enough fuel for about 100 miles of motoring.

Under genoa alone and with a choppy sea they are only sailing about 60° to the wind which gives them a course to leeward of the rhum line and is quite slow.

They would love to return to Ireland but Jack needs to get back to work.

What is the best plan?

James Stevens answers:

I think Jack and Grace should save their engine hours until they are near the hazards off Land’s End.

Sailing to windward under jib alone at sea is frustrating.

Every wave knocks the bow to leeward.

Even with the headsail unrolled, being a fractional rig there is insufficient sail power to make progress.

It would therefore make a big difference if they could improvise some more sail.

Continues below…

Navigation

James Stevens, author of the Yachtmaster Handbook, spent 10 of his 23 years at the RYA as Training Manager and Yachtmaster Chief Examiner

Unfortunately setting a jib as a replacement main with the tack of the jib at the gooseneck rarely works because the clew ends up high off the boom and is impossible to sheet in.

This is because the angle between the luff and the foot of a jib is much less than the 90° it is on a mainsail.

However, the angle between the leech and the foot of a jib is much nearer 90°, which means that if the jib is set with the clew at the gooseneck it will be more effective.

It will take a bit of improvisation to secure the tack to the boom and it will not be a perfect fit.

Also the leech is much weaker than the luff so they will have to be careful about putting too much tension on the halyard.

This is not a strong-wind option but with a bit of ingenuity it can make a difference to windward, especially if the larger jib is used as the makeshift mainsail and the number two genoa is set on the forestay.