Since there seems such an enthusiasim for answering questions......I have another one. This boat (2914) came with a 1974, measured main and a newish jib. A member of this forum kindly donated, free, see previous post re not spending money, a main and jib. This main, Rush loose foot measured in 1992, has a longer foot and a shorter luff than the original lens foot main.
The "new" jib, unknown make seems bigger than our old one all round but certainly longer in the foot. Is there a variation in aspect ratio allowed under the rules? Should sails be in pairs? If the sail donor is reading this then thank you very much. We tried the sails yesterday and we were very pleased. I will email photos when I have them.

John,

The sail plan is described in the Rule book, but in very simple terms, there is a mathematical formula for the allowable proportions of the mainsail foot to luff ratio - this defines the measured area, and the jib area is found by calculation from the mainsail area.
Note that the measurement isn't the actual area of the sailcloth.
The area of the jib should be marked at the front of the boom....

Basically, there's been a move from tall masts (long luff) and short booms, to slightly shorter masts and slightly longer booms.

It's good that it all worked and you're happy!

Good sailing,

Colin (3387)

The main and jib should be in pairs, yes (although you can replace either sail with one of the same size). The mainsail needs to match the mast length.

However, racing a 2xxx boat number (i.e. 30+ years old) , no-one is going to get huffy with you using an unmatched pair! Any sensible competitor will realise that things like tacking well will gain you more places than a slightly larger jib.