Motoring up wind with main sail up

sebastiannr

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I've tried to find an answer to this question on here but failed, so apologies if this has been asked and answered before.

Today I was motoring up wind at about 20 degrees to the apparent wind. I didn't bother to take down the main as it gave a bit of stability and it was still full. There's obviously no way I could sail that close, so would the sail have been slowing me down despite not being backed? Or would it have just given me leeway? Or would it have been actually giving me some forward drive? The apparent wind was 11-14 knots, sea was calm to moderate. My sail isn't new but neither is it excessively baggy. I found difficult to tell the effects of having the main up on my speed by observations alone. It would be good to know at what point the main is actually hindering your forward progress and how to tell when you're at that point.
 
I've always found that the main offers a little assistance provided its full of wind and drawing and you don't sheet it so that the boom is above the centre line. I have certainly not ever noticed any drag from a raised main slowing us down.

We often put the main up if we are motoring in no wind at all as it tends to reduce rolling. I will admit that I am often sad enough to put the motor-sailing cone up as well.
 
If the main is actually shaped and drawing, ie not back-winding or fluttering then you will be getting lift from it.
 
I've tried to find an answer to this question on here but failed, so apologies if this has been asked and answered before.

Today I was motoring up wind at about 20 degrees to the apparent wind. I didn't bother to take down the main as it gave a bit of stability and it was still full.

I think you answered your own question. Just by giving the boat more stability you are making the prop more efficient. If we need to motor sail upwind we will normally tack through about 60 deg, this gives us an extra 1/2 - 1 knot on the speed as opposed to just motoring. Motoring dead upwind is horrible and I would choose to motor sail with the main full every time.
 
I've always found that the main offers a little assistance provided its full of wind and drawing and you don't sheet it so that the boom is above the centre line. I have certainly not ever noticed any drag from a raised main slowing us down.

We often put the main up if we are motoring in no wind at all as it tends to reduce rolling. I will admit that I am often sad enough to put the motor-sailing cone up as well.

There's nothing sad about being proper. I will however admit that I am rarely proper enough to put up the motor-sailing cone.
 
IMHO if the sail is full and not fluttering/backing, then it is drawing and positively contributing to your forward movement as well as delivering the stability. The amount of leeway you would make under such circumstances (assuming reasonable speed) would be negligible.
 
It's full and drawing so it's probably providing some forward propulsion.

It's probably not backed, because there's no foresail to modify the airflow onto the back of the sail.

Probably...
 
I usually motor upwind with the wind at about 20 degrees True. The sail will just about be full. I don't think it pulls much but the steadying effect adds to the total boat speed, especially if there is anything of a sea. I usually reef more than I would sailing to keep the heeling to below the 15 degrees that might starve the engine of oil.
 
His Highness Tom Cunliffe did a little piece in YM recently about the benefits of setting your sails to benefit from apparent wind when motor sailing upwind. Rather than motoring directly upwind, sail slightly free-er. You'll sail further but faster and more comfortably.
 
one is not motor sailing with just a main sail set.
One motor sails with all plain sail set

How do I say this politely?

Not true...

or

I believe you to be incorrect...

There's nothing in IRPCS about how many sails you have set. No reason why you shouldn't sail with just the main, and hence no reason why if you are motoring with the mainsail up you shouldn't show that you are motoring by putting a cone up.
 
Erm, forgive me but isn't the motorcone part of the COLREGS.

Yes it is - but I am aware that there are lots of people on here who proudly say they don't bother and also claim to only see cones up on sailing school boats.

If you see my profile you'll understand why I usually feel obliged to try to follow IRPCS to the letter...
 
I think I've seen a motoring cone being used about as often as I see dolphins... about once a season, and I see an anchor ball being used about as often as I see swmbo offer to do a anchor drag check in the middle of the night. Rarely.
 
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