A Cunningham is an old concept, and in practical use is a compromise at best.
It pulls down on the sail from a weaker location, above the tack, which is really the definition of a Cunningham.
It was replaced by the downhaul on beachcats because the designers realized the worth in having a powerful downhaul shaping the entire sail from the tack, AND they made room for attaching the blocks to the mast at the bottom (instead of the deck plate) to allow the mast to rotate.
The Cunningham was an add-on in concept and design, that was seldom challenged or changed until Hobie Alter.
The monohulls that need a Cunningham frequently have a fabric halyard holding the sail up, which stretches and needs to be tightened when the wind comes up with a winch and a crank handle, etc.
Beachcats have powerful mainsheets, and downhauls.
If I need more downhaul, my crew uses one arm and pulls, just like it was designed to work nearly four decades ago.
The word Cunningham gets batted around in the catamaran world a little more now because the America's Cup and Olympic NACRA 17s brought cat sailing a little closer to mainstream conversation, and the monohull sailors use terms that they are comfortable with. Even some catamaran manufacturers have recently used these mis-terms in their sales pitches to try to breed familiarity (internal mast "Cunningham").
This is why you get weird looks when you say Cunningham to a beachcat sailor. It is not a familiar term.
It was replaced by the downhaul on beachcats because the designers realized the worth in having a powerful downhaul shaping the entire sail from the tack, AND they made room for attaching the blocks to the mast at the bottom (instead of the deck plate) to allow the mast to rotate.
Good explanation! My first sailing experiences was on a O'day 25 Cruiser, which had a cunningham. Fast forward 10 years to my first beachcat, a Hobie 18, and I'm looking at the downhaul thinking WHT is this thing for? Lol.
timscottyoung wrote: ...thinking WHT is this thing for? Lol.
Gee, I have this moment at least once a day.
Glad to hear someone else does too!
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