dsigned: 3:1 Blue Water Sailing Cat 55' LOA, 20 ft Beam
The idea here is that increased longitudinal stability (LOA) contributes to comfort in swell in a way that beam doesn't. Transversal stability affects righting moment, which affects sail-carrying. But the reality is that the speed is affected by another two factors: weight and cost.
The long cat tackles this two ways. Firstly, the long narrow cat makes the structure between the hulls potentially less expensive to build (for the same mass), and secondly, it allows the cat to fit into a standard trawler slip.
Other features include a domed pilothouse to minimize drag, while still retaining the inverted slope on the windows to reduce glare and heat absorption. The windows are below eye level when standing, but right at eye level when seated, the goal being to keep the roofline low and aerodynamic while retaining the ability to see out and have full standing room.
The other thing that I'm still trying to work into the design in a way that keeps the windage down is gunwales that provide a bit more protection for the crew from waves and wind while underway than simple steel cable. Along the pilothouse there's no windage penalty, and it actually can provide an advantage by smoothing the transition from the hull to the pilothouse. But forward of this, any foot of gunwale is a foot of windage. Possible solutions are a more dramatic slope to the gunwale, a slotted system designed to allow air to pass while still providing some protection from waves.