Motoring up wind with main sail up

one is not motor sailing with just a main sail set.
One motor sails with all plain sail set


I sometimes sail just under main. Not motor sailing.
And sometimes motor sail with the main up. The col regs are different the cone and lights shows my status.

The bridge personnel on a big red tanker are unlikely to know the difference between a Bermudan under reduced sail and a cat rig under full sail.

Please link or quote the col reg rule you base your statement on
 
Back to the OP original question. Lift of a mainsail appears approximately in the direction of rightangles to the chord of the sail. ie the line luff to leach. This lift direction has the component in the direction of pushing the boat sideways counteracted by the keel into heel. A small portion of the lift vector is in a direction of forward . If you let the main sail out then you get more lift in the forward direction but of course this can soon cause a luff loss of shape and loss of lift.
The apparent wind moves towards coming from the bow the faster you go as related to the wind speed. As the apparent wind comes forward so you have to tighten the main boom in towards the centre of the boat to avert luffing. As you pull the boom in you lessen the vector in the forward direction and increase the heeling vector.
So at some point of heading into the wind under motor the forward thrust becomes negligible compared to the overall drag in the wind. Only practical tests with constant engine power constant wind and test with and without main sail up at various angles from true wind.
Yes you can get a very useful steadying effect and this may make the leaving up the main a useful thing but my guess is that 20 degrees of a gentle wind you will get more drag than thrust. In a stronger wind apparent wind will be more like true wind and at a greater angle off the wind you may get useful thrust to augment the engine. good luck olewill
 
one is not motor sailing with just a main sail set.
One motor sails with all plain sail set

Sorry - you are very definitely wrong. Main plus engine is motorsailing by any definition including Colregs.

On the original question, motorsailing with a main, reefed if need be, just drawing enough to heel you slightly, and the engine is certainly a less unpleasant way to get to windward in a hurry than motoring without sail dead to windward. It is also substantially faster than just sailing. Last did it heading into Plymouth from Start Point with about F7 almost on the nose, and with ambitions of a meal and a pint before all closed. Plane to catch next morning as well......

You can usually point up about 20 degrees higher than when under sail only, as well as make far less leeway. The boat slams less than when going dead to windward under power, and generally feels much steadier. You can point up till the luff of the sail is starting to lift, and as long as the leech and back 2/3rd is full, and the sail is heeling you a bit, I'm sure it is still providing some drive.
 
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Sorry - you are very definitely wrong.
Rule 25 e is not at all clear as to "amount of sail"
(e) A vessel proceeding under sail when also being propelled by machinery shall exhibit forward
where it can best be seen a conical shape, apex downwards.



we wont mention Anchor Ball / lights will we
Rule 30
Anchored vessels and vessels aground
(a) A vessel at anchor shall exhibit where it can best be seen:
(i) in the fore part, an all-round white light or one ball;
 
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Unless you have a deadline to meet or you are involved in an emergency situation, why not keep sailing:
otherwise why not consider a motor boat. I sail to get away from engine noise etc......

Mainsail up + engine running + get your cone up. This informs others of your status under the Col. Regs.
"Practice safe sailing".

I am sure you obey the highway code while driving.
 
Unless you have a deadline to meet or you are involved in an emergency situation, why not keep sailing:
otherwise why not consider a motor boat. I sail to get away from engine noise etc......

Mainsail up + engine running + get your cone up. This informs others of your status under the Col. Regs.
"Practice safe sailing".

I am sure you obey the highway code while driving.

Main sail up and motoring, I had a trident 24 bildge keel not the most close winded of beasts... If I had to sail upwind against any current mainsail up and engine on.

I did this for a little more than one season on a 3.5hp Tomatsu, if blowing F3 plus I could maintain steerage without main. With main up as long as it was drawing (not backing too much), I was going faster than under engine alone in a flat calm.

So yes it helps more than you would think..

I think part of the reason is also reduced pitching caused by drive from sail up mast rather than just engine below...

As for Colregs any sail and you should show a cone, most don't but you should...
 
Main sail up and motoring, I had a trident 24 bildge keel not the most close winded of beasts... If I had to sail upwind against any current mainsail up and engine on.

I did this for a little more than one season on a 3.5hp Tomatsu, if blowing F3 plus I could maintain steerage without main. With main up as long as it was drawing (not backing too much), I was going faster than under engine alone in a flat calm.

So yes it helps more than you would think..

I think part of the reason is also reduced pitching caused by drive from sail up mast rather than just engine below...

As for Colregs any sail and you should show a cone, most don't but you should...


And at night
what would you do
 
And at night
what would you do

As I do not have steaming light I would turn off engine and sail, make all reasnoble efforts to be in a safe anchorage/ bar or be far enough form vessels that no one would know :D :D

If caught short stick a temporary steaming light on and become a Power Driven Vessel...
 
I am sure you obey the highway code while driving.

I want to live in your alternative planet... Around Blazingsmoke, a yellow traffic light means accelerate. More cars pass through red lights than green. Signs showing speed limits are to warn the majority of the relative speeds of hazards (cars blocking your progress). Lane markings are to indicate your cross track error and roundabouts are places to leave dozens of traffic lights!

I go sea to escape these morons, but unfortunately many of them have boats.

Rob.
 
we wont mention Anchor Ball / lights will we
Rule 30
Anchored vessels and vessels aground
(a) A vessel at anchor shall exhibit where it can best be seen:
(i) in the fore part, an all-round white light or one ball;

Selective aren't you? You missed out
"(b) A vessel of less than 50 metres in length may exhibit an all-round white light where it can best be seen instead of the lights prescribed in paragraph (a) of this Rule."

You may not like mast-head all-round whites but the rules most certainly do not proscribe them.
 
Main sail up and motoring, I had a trident 24 bildge keel not the most close winded of beasts... If I had to sail upwind against any current mainsail up and engine on.

I did this for a little more than one season on a 3.5hp Tomatsu, if blowing F3 plus I could maintain steerage without main. With main up as long as it was drawing (not backing too much), I was going faster than under engine alone in a flat calm.

So yes it helps more than you would think..

I think part of the reason is also reduced pitching caused by drive from sail up mast rather than just engine below...


+1 I had a Westerly 25 bilge keeler and this was the way to get upwind. Some may scoff at motorsailing but it has helped me sail many long passges in a very small boat. The VMG figure with the main just starting to back is comparable with motoring straight to wind and it is much more comfortable.

From experience on the Fastnet Race pushing up - wind and tide banging into
 
Main sail up and motoring, I had a trident 24 bildge keel not the most close winded of beasts... If I had to sail upwind against any current mainsail up and engine on.

I did this for a little more than one season on a 3.5hp Tomatsu, if blowing F3 plus I could maintain steerage without main. With main up as long as it was drawing (not backing too much), I was going faster than under engine alone in a flat calm.

So yes it helps more than you would think..

I think part of the reason is also reduced pitching caused by drive from sail up mast rather than just engine below...


+1 I had a Westerly 25 bilge keeler and this was the way to get upwind. Some may scoff at motorsailing but it has helped me sail many long passges in a very small boat. The VMG figure with the main just starting to back is comparable with motoring straight to wind and it is much more comfortable.

From experience on the Fastnet Race pushing up - wind and tide banging into

I have started so I will finish .... banging into breaking waves is hard work verging on madness - so when you can motor sail faster and in relative comfort then why not
 
Rule 25 e is not at all clear as to "amount of sail"
(e) A vessel proceeding under sail when also being propelled by machinery shall exhibit forward
where it can best be seen a conical shape, apex downwards.



we wont mention Anchor Ball / lights will we
Rule 30
Anchored vessels and vessels aground
(a) A vessel at anchor shall exhibit where it can best be seen:
(i) in the fore part, an all-round white light or one ball;

Sailorman, it is completely clear proceeding under sail means ANY AMOUNT OF SAIL. Stop confusing the picture, I really don't want to be rude but your previous post on the subject was just plain wrong.
 
Sailorman, it is completely clear proceeding under sail means ANY AMOUNT OF SAIL. Stop confusing the picture, I really don't want to be rude but your previous post on the subject was just plain wrong.

At the risk of confusing the issue, would you consider that a yawl motoring with only the mizzen up to be motor-sailing? I can imagine an officious Continental official taking the view that it was, but I would be sympathetic to the sailor's view that it wasn't.
 
At the risk of confusing the issue, would you consider that a yawl motoring with only the mizzen up to be motor-sailing? I can imagine an officious Continental official taking the view that it was, but I would be sympathetic to the sailor's view that it wasn't.

I don't think you're confusing the issue at all. I know there aren't many circumstances where you would sail with only the mizzen, but its not much effort to put a cone up ?

Actually on reflection it seems to be a lot of effort for some people!
 
At the risk of confusing the issue, would you consider that a yawl motoring with only the mizzen up to be motor-sailing? I can imagine an officious Continental official taking the view that it was, but I would be sympathetic to the sailor's view that it wasn't.

Yep, that's motor sailing......unless he has a anchor ball hoisted in which case he is using the mizzen as a riding sail at anchor.

Its all about setting the right paradigm so the right rules are applied.

Any approaching navigator needs to know, without any doubt, if he is dealing with a vessel under sail, under mechanical propulsion or at anchor.

Simple as that.

As individuals we either observe the rules or we don't - they are quite clear.

Obviously none of the above applies to fishing boats :rolleyes:
 
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Any approaching navigator needs to know, without any doubt, if he is dealing with a vessel under sail, under mechanical propulsion or at anchor.

As individuals we either observe the rules or we don't - they are quite clear.

So we have rounded Duart Point heading back to Easdale Sound and the wind gets up to 25-30 knots on the nose wind over tide with big lumpy seas coming down Insh sound. We've got two reefs in the main and half the genoa rolled away and our VMG is down to less than two knots. We have an hour and a half to get to the entrance to Cuan Sound or we won't get home. The only other traffic around is the Colonsay ferry heading towards Oban.

I roll the genoa away and put the engine on and begin motor-sailing hard 20 degrees off the wind. The pitching and crashing are horrendous, with green water coming over the foredeck. The next thing I do is go forward and frig about hoisting a motoring cone . . . erm, I don't think so.

Welcome to sailing in the real world.

- W
 
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