PHRF Question

[sailorbri]

Hello everyone! My PHRF rating here on Lake Ontario is 219 (NFS). I own a Fractional 24'' known to many as a Farr 727. I am considering going to a 163% gib, which will cost me 6 sec. per mile. I believe this will give me a considerable advantage in light air and on the downwind leg anytime (if we do the sail change.) My crew and I went out the other day and did a point of sail study on both my 153 Pentex and then my light air 163. We found an average increase of 1 knot with the 163 on all points of sail. About 80% of Lake Ontario winds are at or below 10 knots. I''d like to get input from all of you. I can''t make up my mind. Perhaps you guys can do it for me.
Brian

[Jeff_H]

Great boats those 727''s. I would seriously doubt that the larger 163% genoa jib would give you a 6 second a mile advantage over a 150% genoa. To begin with as a fractional rig, that 13% represents a very small sail area relative to your overall sail area. And most of that area is on the trailing edge of your jib which is the least effective portion of the sail and acts in lee of your mainsail on reach. I would sooner think that you need a good quality light weight 155 genoa which pretty much should have all of the speed of the 163 but without the penalty.

Jeff

[paulk]

I am as surprised as Jeff H about the performance difference between the two sails. If the 163 does add a knot to your speed on all points of sail compared to the 153, however, it is improving your performance by a good deal more than the 6 seconds per mile hit that your rating is taking. For example, at five knots it takes twelve minutes to cover a mile. At six knots, it takes just ten minutes. Your net "gain", taking the 6 second rating adjustment into account, would be 1 minute and 44 seconds. Well worth the hit.

[bporter]

That is a pretty big bump for the sail size.

Are the two sails similar in condition, shape, etc.? Or are you comparing an older, stretched 153?

On my boat in Narragansett Bay, we race a lot in the upper part of the bay where the wind is very light in July and August for evening racing. I opted to have two 151% genoas cut, one heavy with an optimal range of anout 7-14 and one light with a range of about 1-9. The cloth is lighter and the sail is cut more full on the light wind. So we don''t take the penalty for an oversized genoa and we have some light wind ammunition.

I avoided the larger sail because you pay that 6/mi no matter what the conditions are. When it''s blowing 20 I don''t want that handicap. For me, that''s 10% of my rating...

[paulk]

Bporter is right to maximize the results of his sails without taking a rating hit, but it sounds like the original questioner already has the larger sail. In his ca since he''s not thinking about going out and buying a new sail, but already has it in hand, it makes sense for him to use it if it gives him an extra knot on all points of sail. On the other hand, if he was to purchase a new 153 sail, and found that it also increased his speed by a knot on all points of sail compared to his old 153% jib, he''d be even better off using the new 153% jib, since he''d be sailing a knot faster and not taking any rating hit at all.