Fractional Rig vs. Mast Head Rig

[Jeff_H]

Chef2sail:
First of all I hope that you can accept my humble apology. I am sorry that my earlier post came off as being a put down. I in no way intended it that way.

What I did intend to say in abreviated form in the perhaps poorly written sentence in question was three separate points.

1. The sailing qualities and pointing ability of fractionally rigged boats can vary quite widely, just as on masthead boats, and without knowing what specific boats your are racing, its hard for me to comment on their sailing relative abilities.

2. At least at the higher levels of racing, masthead rig boats do not point any higher than fractionally rigged boats, which is partially why so many modern grand prix level race boats are fractionally rigged.

3. In most cruising applications, masthead rigged boats do not point higher or have a better VMG than a comparable masthead rigged boat.

My other point that I intended to make during my post is that the difference in pointing angle that you have observed may not be the result of the differences between fractional and masthead rigs but may be the result of other factors. More specifically, hull and keel form and that fact that the fastest way to sail any particular boat upwind typically varies with the boat's hull and keel typeform as well as rig.

Modern hullforms can have big VMG gains by footing off slightly due to potentially significantly higher speeds through the water and reduced leeway. These kind of boat speed gains when footing a few degrees are less dramatic on older hull and keel designs, such as your C&C 35, and so their best VMG may occur by sailing a few degrees higher than a more modern boat. Different courses for different horses.

Respectfully,
Jeff

[dave6330]

How do you "depower" a mainsail on a fractional rig with the adjustable backstay? We have that kind of rig and (to my great embarasment) I've forgotten what to do with it...

We have a block and tackle assy on one leg of the cables securing the backstay that flexes the mast but, being the timid kind of guy I am, I just keep the thing tight enough not to be loose but with no real tension on the backstay at rest.

Am I doing something wrong or am I simply not maximizing my options?

Dave

[Sasha_V]

You crank on the backstay tension, and alos the outhaul. This flattens the sail to depower it and also moves the centre of effort forwards.
Now is also a good time to ease the traveller somewhat and crank on the cunningham. The boat will stand up and be more controllable, and will lose only a little speed (or it might even gain it depending on how much heel you had before). It will not point quite as high any more, but it will be worth it for the savings in crew energy and sanity. Do not forget to undo all of these tweaks when going downwind and als when you have arrived back at the dock...Nothing worse then seeing a bunch of top-end race boats at the end of a day with their masts still cranked and bent back.

Sasha

[dave6330]

KEWL!!!!

Some new tricks to try this Summer!

Thanks.

[sailingdog]

Just remember, tightening the backstay on a fractionally rigged boat flattens both the mainsail, by curving the mast, and the headsail, by tensioning the forestay.

But you do need to use it in conjunction with the cunningham and the outhaul to get the best results.

[Sasha_V]

One of the things I LIKE about the masthead rig with baby-stay is that you can pretty much bend the mst and depower the main without effecting the headsail....Not that we have ever needed to do that in practical terms, mind you....
And I would think it would leave the boat a bit unbalanced ....


Never mind, nothing to see here....


Sasha

[mlsalwa]

Great thread guys, Thanks.

[max-on]

With all the benefits and versitility a frac rig offers, why are not all modern cruisers, say 40-50 ft, designed with a frac rig instead of a masthead rig, especially as most cruisers are a couple?

[chef2sail]

No pronlem John H. Your threads and posts are very informative

[Faster]

Originally Posted by max-on

With all the benefits and versitility a frac rig offers, why are not all modern cruisers, say 40-50 ft, designed with a frac rig instead of a masthead rig, especially as most cruisers are a couple?

Good question, Max...

In fact, several manufacturers are leaning towards fracs, such as Hanse and Bavaria, some Hunters but in some cases the "I" measurement is such that they are 15/16 rigs or greater... one has to wonder if there's any real "advantage" at that stage.

I think in general the typical masthead rig is perceived as a more robust arrangement, less "tweaky" and many cruising sailors favour ruggedness and stability over performance enhancing strings to pull.

As mentioned earlier, the really tweaky rigs that require careful and constant attention to running backstays and checkstays is just too labour intensive for most. However there certainly are plenty of fractional rigs (ours included) that do not rely on such arrangements.

Another factor is that the mast clearance tends to be lower as the frac needs a taller rig to achieve the sail area since the headsails don't provide as much. Mast clearance is a big issue for East coast boaters on the ICW.

To some, I think any frac rig is percieved as a racing one, and may be rejected out of hand by some cruiser types.