Footed mainsail w/ flattening reef

[Sailormon6]

I have always used a shelf-footed mainsail with a flattening reef, and attached to the boom with a bolt rope, for racing and cruising. Recently I was told that is old technology, and that the current state-of-the-art is the loose-footed mainsail. I now see that the America''s Cup yachts appear to be using mainsails that are attached to the boom, and not loose-footed mainsails. If the loose-footed mainsail is state-of-the-art, then why are the AC boats using "old technology.?" Can anyone explain, or have I been misinformed?

[jparker11]

You are picking on a pet peeve of mine!! I was "forced" to go to a loose foot on the last new mainsail (2000) that I bought. I must admit, shaping the lower one third of the mainsail, especially at the luff is much easier and better with the loose foot.

However, I am very uncomfortable with the lack of redundancy and the resulting mayhem which occurs with a blown outhaul or tack. Most outhauls were designed for horizontal forces only, not the entire sail tack loads. I have seen too many of these loose footed retrofits blow out in above average wind conditions, leaving the skipper at the whim of the headsail or auxiliary in nasty seaways.

As for AC cup use of shelf footed, my guess would be the design criteria is for a very restricted wind range. And with unlimited budgets, you can have the shelf cut in custom manner to act like a loose in reaches, and sail shaping rigging to take advantage of this cut while reaching. And, I believe we commoners have been encouraged economically by sail makers to abandon the bolt rope/slugs of the old shelf foots.

My $.02

[paulk]

Would like to disagree with jparker on the foot loads on a mainsail. Most of the "shelves" on older=styled mains including the ones on our old mains, were of really light material because there isn''t much strain there. The theory was to create an "end plate" effect between the bottom of the sail and the boom, and all that was needed was something to keep the wind from going through. 3/4 oz Spinnaker cloth would have worked except it might have gotten chafed through or snagged on things too easily. Big outhaul and tack loads were then and are now carried by the heavier dacron (or composite whatever) panels in the aerodynamically shaped section at the bottom of the sail. This is why the "flattening reef" has dissapeared; it is added weight, and the current thinking is that there is better flow over the bottom section of the sail- less turbulence and more laminar flow- without an "end plate". It''s also cheaper to make and buy a sail without a footrope. We worried that folding a loose-footed main would be more difficult, but it really isn''t.

[Jeff_H]

The AC boats use shelf foot mainsails because of an anomoly in the America''s Cup Class measurement rule that favors a shelf foot.

Jeff

[waltward]

Jeff_H & All

How do you feel in general, pro & con, about the loose foot? I hae a Capri 30 and she is going to need a new Main soon. I would appreciate your thoughts.

Thanks----Walt Ward
waltw@unnet.com -------- above e-mail is wrong

[Jeff_H]

I really like loose footed mainsails, especially on a compartively small, performance oriented boat like the Capri 30 (always a real favorite of mine as an inexpensive boat to go PHRF racing).

Jeff