Hi does anyone know of some popular or usuall mast height/hull length ratios for cats smaller than about 15ft?
Cheers guys

It seems many boats have masts that are 150% the hull length.

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Greenville SC

Offering sails and other go fast parts for A-class catamarans
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H-14 Mast 24 feet approx 171% of boat length
P-16 Mast 26 feet approx 163% of boat length
H-16 Mast 26 feet approx 156% of boat length (Boat is actually 16 feet 7 inches)

HULLFLYER

H-14 Mast 24 feet approx 171% of boat length
P-16 Mast 26 feet approx 163% of boat length
H-16 Mast 26 feet approx 156% of boat length (Boat is actually 16 feet 7 inches)

According to the Hobie site, the H-14 mast is 22'3", not 24' (166%)

I'm sure it, isn't as simple as a percentage of length. Several other variables must be considered. The boat width for one, the wider the boat the more righting moment you will have so you can put more sail up higher (8.5 ft is normally the max). The anticipated crew weight, again the heavier the crew the more mast you can put on. The weight of the hulls. The sail plan (flat top vs pin top as well as sail area and the amount of roach).

To get around the all that if you are building your own, I would use the rig off of a similar sized cat. If you are modding a cat and want a bigger rig just be aware that if you push it too far you may find your cat to be very very difficult to sail. With my 5.2 I put a huge custom flat top sail on it (essentially the same as extending the mast several feet) and found that I can't solo it anymore. I need a fairly good and beefy crew to keep it down in any wind approaching big. However, when I do get it out it's incredibly fast!

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Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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Awesome much appreciated guys

if you are going to add extra power to your boat, try to find oyt where the cetner of force is then you will have an idea of how the additional mast and sail will impact you. I converted my P18-2 with a 27ft 9 in mast and factory pin top of 233 sqft to a 30 ft p19 mast and monster P19MX main and custum 19 jib for about 285 sq ft. with the square top it really moved CF up so to harness the power takes a little more nerve but if you can keep from going over or driving under. nothing and no one is goin to catch you :)

" no such thing as over powered, just lack of bouyancy and ballast :)