JIB TACK LEADER PLUS DECKSWEEPER PLUS TRAVELLER

" THE CHORD IS THE KEY "

Definition: [SAIL POWER-page 54]- The chord is a straight line drawn horizontally from the luff to the leech at any height in the sail

Having the proper foresail sheet fairlead location, ensuring proper leach and foot tension, is essential to the foresail [jib or genoa] performing well on a MATILDA. Many MATILDAS use the gunnel track fairlead block for trimming their jib foresail as well as their genoa foresail. Both sails require the proper fairlead location to perform well. The gunnel track is ideal for beam and broad reaches with a genoa foresail, however when going to windward with the jib foresail, the outside track is less than ideal. Many other boats use a similar gunnel track [because it is convenient] but not many other boats have the broad beam to length ratio of a MATILDA.

Athwartship Location[sheeting angle]
The biggest area of concern is the angle of the foresail fairlead block location. Using the outside track, with the block right at the front of the track, gives you a sheeting angle of 24degrees, when you should have an angle of 10-12degrees to allow the jib and mainsail to complement each other [as well to properly tension the foot and the leach of the jib]. Moving the fairlead aft, as when using a genoa foresail, the angle decreases to less than 24degrees [under the rear corner of the window gives a sheeting angle of approx. 18degrees] which is acceptable for beam and broad reaches. This observation explains why MATILDA owners, who install a genoa foresail and head out in medium strength winds, find their craft performs reasonably well, but then the breeze freshens and they decide to switch to the jib foresail [because of the reduced sail area] and then find out they can not perform to windward as well with the smaller sail.

Fore and Aft Location
For a starting point for the fore and aft location of the fairlead, [for a jib with the following dimensions foot=104", luff=264", leach=244"] it should be on the extension of a line drawn from a point 60% up the luff through the clew [ this position has to be adjusted depending on wind strength].

Sailing by the luff is a time honoured method of sailing to windward but keeping the jib sail just on the verge of luffing is very demanding of the helmsperson. It is easy to see when you are sailing too close to the wind [the sail shakes at the leading edge and you need to fall off the wind a bit] but it is difficult to determine when you are sailing too far off the wind. A good masthead wind indicator helps [mine keeps telling me to head up when sail is not on the verge of luffing] and telltales on the front part of the sail-back about 8" from the leading edge and placed at 1/4, 1/2, and 3/4 up the leading edge-help to tell you how to improve the trim of your sail.

The leader is made up of 1/8" 1X19 stainless wire with a thimble nicropressed on each end[two sleeves used on each end because of the slow spiral of 1X19 wire] to give an overall length of 10" [14" would have been a better length] in an effort to raise the sail to give an improved fore&aft location because the front end of the tracks terminate at the chainplates.

If you can not move the fairlead forward, RAISE THE SAIL. Raising the sail allows you to achieve a tight leach, without tensioning the foot too much, which reduces the power of the sail.

Installing a leader on the jib sail of a MATILDA will help to improve the windward ability by a limited amount and will eliminate the spectacle of a jib sail with a very open leech.

However, the biggest improvement in a MATILDA's pointing ability will be achieved with the installation of inboard jib sheet fairlead tracks. [See INBOARD JIB SHEET FAIRLEAD TRACKS]

P.S. It is essential to have a leader if you are going to install inboard jib sheet fairlead tracks.



DECKSWEEPER JIB

Several people have commented that having a leader on the tack of the foresail raises the foot of the foresail which loses the decksweeper effect of the foresail.






As you can see in the above photo, the MATILDA on the right with a raised jib, appears to have a larger bow wave [going faster??] than the one on the left, with a decksweeper genoa. Both are using the gunnel track for fairlead location. A craft with a flush foredeck is a different story but a MATILDA with the front of the cabin in the airstream [which probably has a negative effect] will not benefit greatly. In my opinion, it is more important to direct the power of the wind to where it can be utilized e.g. the leeward side of the main, than it is to capture all the wind and direct it over an area where it will have no effect e.g. the area below the main sail.
In my opinion, the ability to have a tight leach on the jib, that parallels the main sail rather than an open leach, is more critical than a decksweeping foresail.



The Slot effect from MAXIMUM SAIL POWER
by Brian Hancock
Chapter 15 page 241 Circulation Theory
[An excellent treatise on the latest thoughts on the slot effect]
In order for two sails to have a symbiotic relationship, they have to be in relatively close proximity to one another [24degrees is too far apart for the sails to impact one another]
P.S. It is interesting to note that the chord of the foresail in the illustration is approximately 14degrees.




TRAVELLER

A traveller is a very useful tool for controlling the main sail in relation to the centerline of the boat as well as influencing the shape [power] of the sail.

Advantages
#1. Moving the traveller to leeward, when encountering strong winds, can have an amazing effect on the heeling of a tender craft[See the next 2 photos and accompaning tale]
#2. Moving the traveller to windward, in light airs, allows you to move the boom to the centerline of the boat [which allows you to point higher] without flattening [depowering] the main sail.
#3. Changing to mid-boom sheeting, with a traveller allows you to change from an unsatisfactory main sheet system which is not suitable for windward work.


It is worth mentioning, at this point, that Roger Macgregor, the boat building minimalist, has added a traveller to his latest effort, the NEW 26M. Roger, you can be sure would only add something if it would benefit the boat.


ADVANTAGE #1

They say that a picture is worth a 1,000 words so I will let the next two pictures speak for themselves . Photos from SAIL POWER by Wallace Ross page 132









Main sheet in centre position
[NO EFFECT OF TRAVELLER]












Main sheet to leeward
[TRAVELLER AFFECTING MAIN SAIL]






These two pictures show how differences in trim affect a boat's ability to stand up and to point. DAME PATTIE has her mainsheet trimmed much too close to the centerline and as a result is heeling way over, while INTREPID is trimmed correctly, thus keeping on her feet and making good headway.

After viewing the above photos, I elected to add a traveller to our K-D, with mid-boom sheeting with advantage #1 in mind.
An enlightening tale follows.
On a blustery day at the Wildwood Sailing Club, we noticed a CL16 running down the lake and decided to see if we could catch him. We did manage to pull alongside him, at the end of the lake and we both proceeded to come about for the beat back up the lake. After our first tack, I knew we were in for a challenge because of the strong winds. On our second tack, I moved the traveller to leeward about 8" and an amazing change occurred. We were no longer sailing in survival mode [ using all our talents to keep the boat from capsizing] but were making excellent progress to windward, without the potentially dangerous heeling that we were encountering without the traveller. We proceeded to make further excellent progress to windward but our sailing friend [ a very skilled sailor] continued to proceed back and forth across the lake but was not making much progress up the lake [he was just trying his best to keep his craft afloat].
Halfway back to the club, another skilled and knowledgeable sailor, with his wooden sloop that he fancies is quite a racer, elected to change his course and join us in the beat back to the club. After his first tack, he knew that he was in for a challenge but managed to keep going to windward in extreme conditions. He also was not making much progress to windward but was flying from one side of the lake to the other. We proceeded to the club under relatively pleasant conditions as the other two boats continued to thrash back and forth across the lake.
I WAS REALLY AMAZED AND IMPRESSED. Just 8" to leeward made all the difference between a sail in challenging conditions to a sail in less demanding circumstances. I know it is very satisfying to survive a sail under demanding conditions [Yes, I too, have kissed the "terra firma" after surviving a interesting sail] but it is comforting to know that going to windward doesn't have to be so punishing if your craft is properly equipped for such conditions.What is really amazing is that we made so much progress to windward and were far, far more comfortable.
Prior to installing the traveller, our technique for sailing to windward in strong winds, was to sheet the jib as tightly as possible [the jib alone should never have enough power to capsize you] and luff the main when capsizing seemed imminent and NEVER, I repeat, NEVER cleat the mainsheet.This technique has served us well in the past, until the wind gets so powerful that it gets under the hull [because you are on such an angle of heel] and you find that easing the main has no effect and then, you go swimming with your boat.
When you are sailing to windward, you are tempted to pull the main sheet as tight as possible [pulling the boom to the centerline] so that you can point as high as possible. You also want the boom as low as possible to flatten the sail [flat sail reduces power in strong winds]. This is a recipe for trouble as it results in excessive heeling. Having a traveller allows you to pull the boom down [flattening the sail], without pulling the boom to the centerline.
Another aspect that became clear was that a rope and pulley system for adjusting the traveller car was not really necessary, as adjustable stops, set by just retracting a pin, was more than adequate for beating to windward with a traveller.

So, to all the tender boat owners out there, adding a traveller to your craft, will allow you to cope when the wind strength increases.

I question whether a traveller is really necessary on a MATILDA as the craft is so inherently stable and will stand up well to increased wind much better than a more tender craft. In fact, our MATILDA seldom ever reaches the angle of heel that our K-D sailed consistently well at [like it was on rails] with the one side under water and the water coming in at the front of the seat and exiting at the rear of the seat.This opinion may change after I have converted our MATILDA to mid-boom sheeting. It may be found that a mid- boom sheeting system allows you to pull the boom much closer to the centerline than the existing CROSBY rig does, which may dictate the necessity of a traveller.



ADVANTAGE #2
Moving the traveller car to windward, in light air, should allow a boat to point higher by pulling the boom to the centerline without exerting significant downward pressure on the boom, [ flattening the sails]. In light air, you want the sail shape to be full and powerful.

ADVANTAGE #3
The original main sheet configuration [CROSBY RIG] of a MATILDA leaves a lot to be desired for Sailing to Windward.
A. When you are on a starboard tack, the main sheet comes across the cockpit and you can easily control the main sheet [cleat, release, adjust in or out].
B. When you are on a port tack, the main sheet is behind you and you must some how manage to cleat and uncleat the main sheet. Certainly not an ideal situation if you are in gusty winds where you must be prepared to uncleat the main sheet immediately when a gust hits and tighten the main sheet when there is a lull.
C. The CROSBY RIG configuration does not pull the boom to the centerline adequately. Once you are at point A on the travel of the boom, you are close to the limit of how close to the centerline you can move the boom with the mainsheet.
D. End of boom sheeting is less preferable to mid-boom sheeting because when you are attached to the end of the boom, pulling down on the end does not exert any effort [ other than the structural strength of the boom] on the mid point of the boom, where the sail [ because of the wind's pressure] is trying to pull the boom up. A mid-boom sheeting system puts the downward pull of the main sheet directly under the sails upward pull.
E. Use of a traveller at the end of the boom has to have twice as much range of movement to be as effective as a mid-boom attachment point, e.g. 8" of mid-boom movement dictates 16" of movement at the end of the boom.
F. Use of a traveller [which some people call a horse] between the stanchions of the rear pulpit has a limited range of movement- 13" range of movement divided by 2 = an offset of 6 1/2", at end of boom, equals 3 1/4" on a mid-boom arrangement. But the biggest problem is the tremendous aft pull of the mainsheet. There is a MATILDA at the W.S.C., with the horse [traveller between the stanchions ] as original equipment and he has had the boom detach from the gooseneck because of the aft pull of the mainsheet [ the nut holding the spring mechanism for the rolling boom furler became undone]. Definitely not something you need to happen in strong winds. So if you have the HORSE set up, be sure to use loc-tite on that nut.
G. Using end of boom sheeting [whether CROSBY RIG or HORSE ] tends to make the helmsperson sit towards the rear of the cockpit seat. A mid-boom sheeting system tends to move the helmsperson to the middle of the seat [ a definite plus as the last thing a MATILDA needs for proper boat trim is to have more weight in the stern of the boat].