Slamming Main in Calms

[Sulaire]

You are sailing along comfortably when the wind drops away. There is a fair swell running coming in on the quarter or beam. The sails begin to slam and you wish to get to port without sitting out prolonged calm, so you turn on the engine. ( coastal sailing, not ocean passage!)

If you lower sail, the boat rolls uncomfortably, so you leave up the main. This takes away the worst of the roll, but the sail slams violently from side to side even with the boom wound in tight to midships, shaking the whole rig every 10 seconds.

What to do?........ Any sage advice (apart from buy a motorboat)!

Charlie.

[Blue Stocking]

You could rig a preventer to immobilise the boom.
Check for correct side for when the wind comes back.

[conachair]

Originally Posted by Sulaire

You are sailing along comfortably when the wind drops away. There is a fair swell running coming in on the quarter or beam. The sails begin to slam and you wish to get to port without sitting out prolonged calm, so you turn on the engine. ( coastal sailing, not ocean passage!)

If you lower sail, the boat rolls uncomfortably, so you leave up the main. This takes away the worst of the roll, but the sail slams violently from side to side even with the boom wound in tight to midships, shaking the whole rig every 10 seconds.

What to do?........ Any sage advice (apart from buy a motorboat)!

Charlie.

Not onshore but offshore drifting waiting for wind the best setup I could manage was 3 reefs in the main and sheeted hard in. Even in an oily calm there always seems to be some swell the rip your nerves apart with a slatting main. Only time I've ever needed the 3rd reef
Then a very large book and lots of patience, sometimes a few days of that

[Sulaire]

Hi, thanks

The boom is wound in to midships and does not move in the swell, but the sail is fully battened and even though i tighten everything up ( outhall etc), the main still has a belly that flicks from side to side causing this slamming. Tried a preventer with the boom out to one side slightly, but same result, tried taking in a feef or two, same result.

Tried most things and put it down as just one of tose things...., but on a long passage the other day I sat looking at the rig trying to figure out a cure with no luck and wondered if anyone had a solution. I have a feeling it is just all part of the enjoyment of sailing!!! In which case i will survive ( not sure about the rig though! ).

C.

[Cheechako]

I always had a big 4 part tackle for my Boom Vang. Big snap shackle at each end. In your situation it would take about 1 minute to rig a preventer with that. Pulled partially to one side, with the mainsheet the opposite direction creates a solid triangle of support. If your sail has a lot of belly or a shelf at the bottom you may have to put a reef in to keep it from slapping some above the boom.

[zeehag]

i prevent my booms from flogging so i dont have to repair em.

[Randyonr3]

preventers dont work in your situation.. its the sail whipping.. drop the main and tie it off, keep your staysail up to keep the roll of the boat down and approach your destination at a different angle,
you may have to do a zig-zag pattern to get back home ..

[Sailmonkey]

I've done the reefed main with a preventer, when that doesn't work I've resorted to a 90% headsail poled out with tripod support for the pole end. It still slats, but nothing like the main!!

[Sulaire]

Originally Posted by Randyonr3

preventers dont work in your situation.. its the sail whipping.. drop the main and tie it off, keep your staysail up to keep the roll of the boat down and approach your destination at a different angle,
you may have to do a zig-zag pattern to get back home ..

Thanks evryone for the ideas, randyonr3, that is a solution i have tried and is indeed the best i have found so far.

Not charging straight to your destination under power but putting a little apparent wind in the sail also helped keep it steady, but the wind don' t always do what you want !!!!!!.......

I feel every slam like a dagger, my poor boat is suffering.... I do not like my boat to suffer!.....

C.

[Tingum]

Duh! Drop the main, no sense in abusing it.

[Sailmonkey]

Originally Posted by Tingum

Duh! Drop the main, no sense in abusing it.

When you're 500 miles from land and only carry 400 miles of fuel, you need to cover some ground.......so then what do you do. I've already posted what I do.

[tillybobs]

I think he did say coastal sailing only

[SkiprJohn]

It is nerve racking and something I've never quite gotten used to. Knowing too that at each slat the strain on the sail stitching is making it become weaker. I think the only answer is to drop the main and motor. If there are no ripples on the water then there won't be any sailing. I haven't tried a flat staysail rigged in tight but that might be an option. It'll still slat as the boat rolls from side to side.

As you've said, if the boom does not move and it is tightened down as hard as you can get it there isn't much point in putting more pressure on it. Just going to break something.

maybe there is no answer to this one.

kind regards,

[Jim Cate]

We have permanent vang/preventers rigged and these stabilize the boom (as others have suggested). But the sail still slats as you know all too well... so we also put in two reefs. This both flattens the sail greatly and reduces the mass of sailcloth that is whacking back and forth, and the combination markedly reduces the loads on both sail and rig and still offers a bit of roll damping.

It is still not nice, but at least on our boat it is much less agonizing.

[DeepFrz]

I have always wondered why sailors don't use "fish" (flopper stoppers) when motoring or sitting mid ocean waiting for some wind. A long proven method for fishing and cruising trawlers.