Flying a masthead spinnaker on 3/4 rig

[jastic]

Please reread your own posts #47 that I quoted. You said ‘poled out’, but if using the main boom you never specified that. However, even then you should be able to furl the genoa instantly.
However, your combination of arrogance and ignorance is not very endearing.

I sincerely apologise if I have appear arrogant, that not my intent, but I'm not ignorant, the repeated suggestion I should run an A sail and sail the angles I find tiresome! I have been there, done that (as I stated early in this discussion) and it simply has never paid off.

 

[flaming]

All line handling with the engines running has it's risks, the key is to be aware of the risk and seek ways to mitigate it. The spiked sheets and guy will already be safely on the foredeck, the working sheet and bow guy will still be attached so limited in there ability to dive overboard. The snuffer line will be at the foot of the mast so well out of harms way

Yes. The best way of mitigating it is not to have the engine running…

I mean, I fly kites every single time I sail, racing doublehanded and fully crewed.

The idea that even with that level of experience I could mitigate rope round prop to an acceptable level is not something I’d sign up to.

I sincerely apologise if I have appear arrogant, that not my intent, but I'm not ignorant, the repeated suggestion I should run an A sail and sail the angles I find tiresome! I have been there, done that (as I stated early in this discussion) and it simply has never paid off.

if a technique that works for thousands, and is standard practice isn’t working for you, then I’d honestly try to find out why that is before you do anything to risk your rig.

Your proposed solution to better speed in light winds goes against everything that I’ve ever learned about making downwind progress in the light.

It also leaves you spending money on a sail that will only work in a very limited wind angle and speed.

It’s your boat, and your call, but I don’t think I could be any clearer in why I think you’re making a mistake….

 

[jastic]

if a technique that works for thousands, and is standard practice isn’t working for you, then I’d honestly try to find out why that is before you do anything to risk your rig.

Your proposed solution to better speed in light winds goes against everything that I’ve ever learned about making downwind progress in the light.

It also leaves you spending money on a sail that will only work in a very limited wind angle and speed.

I take it you think the Parasailor is witch craft?
And I'm not alone here's a quote from Richard Woods (designer woods catamarans) "Over the years I've raced many times with a conventional spinnaker against competition using asymmetrics. Yet it has been only on rare occasions that the asymmetrics have been significantly faster. So my recommendation is that cruisers (especially those with slower boats) use a conventional spinnaker."

 

[flaming]

I take it you think the Parasailor is witch craft?
And I'm not alone here's a quote from Richard Woods (designer woods catamarans) "Over the years I've raced many times with a conventional spinnaker against competition using asymmetrics. Yet it has been only on rare occasions that the asymmetrics have been significantly faster. So my recommendation is that cruisers (especially those with slower boats) use a conventional spinnaker."

Not what I’m saying. In breeze - circa 10-15 or more, then I absolutely endorse symmetrical kites for cruisers. But that’s not what you’re trying to do. You’re trying to boost speed in light winds. And you’re trying to do that with a symmetrical kite set without a pole. If you do that you won’t be able to sail angles. And if you don’t sail angles in sub 10 knots you will be slower than the boat with the same sails, regardless of if that’s a symmetrical, A-sail or whatever.

Just to reinforce what I said earlier. When racing boats specify sails for LIGHT wind downwind, they are SMALLER than the same boat flys in 10-20 knots. And flatter, and designed to sail angles.

What you’re specifying in asking for a large symmetrical kite is something we specify for 10-20 knots. NOT sub 10.

 

[jastic]

NOT sub 10.

I actually said max 20 but preparing to drop at 15 (if it's steadily rising). I whole heartily agree with you, if you are racing (or pseudo racing) and prepared to work the shifts, calculate the perfect points to jibe, and you are running a "light" boat you will be faster with an A sail. I'm a cruiser, I like to make "good progress" but not at the expense of my lunch in the cockpit washed down with a glass of rose and short nap. Horses for courses.

 

[flaming]

I actually said max 20 but preparing to drop at 15 (if it's steadily rising). I whole heartily agree with you, if you are racing (or pseudo racing) and prepared to work the shifts, calculate the perfect points to jibe, and you are running a "light" boat you will be faster with an A sail. I'm a cruiser, I like to make "good progress" but not at the expense of my lunch in the cockpit washed down with a glass of rose and short nap. Horses for courses.

Ok. But you said that this sail was because you wanted to go faster downwind in 5-10.

A big kite and heading DDW is not the way to go in 5-10.

If you’d said you wanted to have easier hull speed in 15 then fine. But that’s not what you said.

 

[dunedin]

I sincerely apologise if I have appear arrogant, that not my intent, but I'm not ignorant, the repeated suggestion I should run an A sail and sail the angles I find tiresome! I have been there, done that (as I stated early in this discussion) and it simply has never paid off.

When you posted earlier on “ Any riggers or architect out there?” to my mind that is at best naivity to expect a rigger to come on here and tell you whether you can put potentially huge extra loads on the top of a mast without having giving any info on
- the type of boat
- the mast material (carbon or aluminium), maker and section
- the existing rigging (eg what backstays, if any, at what height; height of upper shroud attachments)etc
Belatedly many posts later you mention the boat type, but no other info needed to make any sensible input other than it is a big risk on a boat not designed for a masthead spinnaker.

PS. On the Atlantic crossing we did the boats with Parasailor symmetrical kites had a nice trip, but were a VERY long way behind us (days later), and we had a simple white sail rig of main plus poled out Yankee genoa. Parasailor only didnt seem a fast sail,plan.

 

[jastic]

Ok. But you said that this sail was because you wanted to go faster downwind in 5-10.

A big kite and heading DDW is not the way to go in 5-10.

If you’d said you wanted to have easier hull speed in 15 then fine. But that’s not what you said.

Well my OP was "I plan to fly a masthead symmetrical spinnaker on my 3/4 fractional rigged 12m cruising catamaran in up to 20 knots true between 150/180 degrees". I agree being able to turn the motors off and get moving in 5-10 knots, albeit slowly, is also the plan. My opinions are based on my experience with my previous catamaran which I had for 16 years. It was an FP Maldives 32, 3.5t with a lift up central outboard and a generous sailplan. I ran an A sail (on bridle) and a large (masthead) code 0, she was easily driven so got moving quickly. My experience was that I'd set off sailing the angles, juggling the shifts and the tides down the Brittany coast and after an hour would fined myself converging with the same wing on wing mono that I'd started off next too. I concluded that unless you are skilled and truly dedicated it's a thankless task. My current boat is less sporty and I'm now even less inclined to spend all day "fretting about the angles".

 

[jastic]

When you posted earlier on “ Any riggers or architect out there?” to my mind that is at best naivity to expect a rigger to come on here and tell you whether you can put potentially huge extra loads on the top of a mast without having giving any info on
- the type of boat
- the mast material (carbon or aluminium), maker and section
- the existing rigging (eg what backstays, if any, at what height; height of upper shroud attachments)etc
Belatedly many posts later you mention the boat type, but no other info needed to make any sensible input other than it is a big risk on a boat not designed for a masthead spinnaker.

PS. On the Atlantic crossing we did the boats with Parasailor symmetrical kites had a nice trip, but were a VERY long way behind us (days later), and we had a simple white sail rig of main plus poled out Yankee genoa. Para-sailor only didnt seem a fast sail,plan.

scroll out, I did not give the full rig spec because I was not looking for detailed advice, purely views/thoughts on the suitability of using of using the topping lift/main sheet to give additional support to the top section. Bravo on outpacing the parasailors I bet they were miffed....

 

[oldbloke]

Quite right, I have made no mention of crossing oceans, I crossed Biscay last year (Gijon-La Rochelle) and this year the longest passage will probably be Ushant - Scilly and maybe Baltimore- Scilly if the weather is fair.
On the Biscay crossing we had 5-10 knots pushing us down wind for the first 5 hours, the masthead spinnaker would have kept us moving quite nicely. That's the use to which it will be put, light airs, dead down wind. I quoted 20 knots to give a margin for error, as we approach 15 we will be preparing to drop. Thanks again for your support, given most of the drivel this post has generated it's not likely I'll post again in the near future and if I do, I'll make the question crystal clear and state what I don't want to hear about!

Apparently Ushant to Scilly is only 35 leagues. Hardly seems worth the effort!!

 

[jastic]

Apparently Ushant to Scilly is only 35 leagues. Hardly seems worth the effort!!

Remarkably accurate given it was written in the late 1700's, now all I need is 10-15knots from the SE I'll sing it all the way there!

 

[Laser310]

I have a fair bit of experience racing and delivering large high performance catamarans in the 60-70ft range.

I had done probably 12-15000 ocean miles on them, including an Atlantic crossing.., all with asyms.., before i got on one with a slightly more cruising aspect, that had a symmetrical spinnaker for sailing DDW, or nearly so.

The symmetrical spinnaker, hoisted without a mainsail is a great setup for these boats.

Yes, with a full crew, willing to sail these boats powered-up, the asym with the main at hot angles is faster. On the ocean in tough conditions, it is not for the faint of heart - these boats will capsize, and the ride can be a bit of a white knuckle experience.

If the voyage is long - say a week or two, it's very difficult to sustain this mode safely with the short crew typical of deliveries.

for one thing, the angles are quite hot, with the consequence that on a true downwind passage, the penalty for being on the wrong tack is quite high - how often do you want to gybe? It's not a dinghy... The hotter the angle, the more important it is to gybe on small shifts.

With a symmetrical spinnaker, and without a mainsail, it is possible to sail TWA 170 or so, at modest speeds, without much drama, and in relaxed comfort. with a main up, you can't get below 130 on a lot of these boats without destroying the sail on the spreaders, they are so swept.

Gybing, when you do want to do it, is very easy.

the typical setup is a tackline and a sheet on each corner. You just take up on the new tackline, ease the old tackline, transferring to the sheet on that side.., no main to gybe. then punch the autopilot to turn 20deg to come to 170 on the new tack. It is the easiest thing in the world, one person can do it.

Now as far as the OP's question about the rig - it depends on the rig... but the boat i did it on has runners, and is probably 7/8.

 

[jastic]

I have a fair bit of experience racing and delivering large high performance catamarans in the 60-70ft range.

I had done probably 12-15000 ocean miles on them, including an Atlantic crossing.., all with asyms.., before i got on one with a slightly more cruising aspect, that had a symmetrical spinnaker for sailing DDW, or nearly so.

The symmetrical spinnaker, hoisted without a mainsail is a great setup for these boats.

Yes, with a full crew, willing to sail these boats powered-up, the asym with the main at hot angles is faster. On the ocean in tough conditions, it is not for the faint of heart - these boats will capsize, and the ride can be a bit of a white knuckle experience.

If the voyage is long - say a week or two, it's very difficult to sustain this mode safely with the short crew typical of deliveries.

for one thing, the angles are quite hot, with the consequence that on a true downwind passage, the penalty for being on the wrong tack is quite high - how often do you want to gybe? It's not a dinghy... The hotter the angle, the more important it is to gybe on small shifts.

With a symmetrical spinnaker, and without a mainsail, it is possible to sail TWA 170 or so, at modest speeds, without much drama, and in relaxed comfort. with a main up, you can't get below 130 on a lot of these boats without destroying the sail on the spreaders, they are so swept.

Gybing, when you do want to do it, is very easy.

the typical setup is a tackline and a sheet on each corner. You just take up on the new tackline, ease the old tackline, transferring to the sheet on that side.., no main to gybe. then punch the autopilot to turn 20deg to come to 170 on the new tack. It is the easiest thing in the world, one person can do it.

Now as far as the OP's question about the rig - it depends on the rig... but the boat i did it on has runners, and is probably 7/8.

your observations and comments are much appreciated!