Design Brief & Intent 3
The core mission of the Supernova was to deliver a "stabilized racing dinghy" that could be easily managed by a single sailor or a couple, while remaining entirely cartoppable or trailerable. At its heart, the boat consists of a narrow, wave-piercing central hull (vaka) stabilized by two slender outriggers (amas) connected via an engineered aluminum crossbeam framework.
In an era when beach cats like the Hobie 14 dominated, the Supernova offered a highly distinctive alternative. Its cockpit-centric layout keeps the crew’s center of gravity low and secure within the central hull, reducing the physical fatigue associated with continuous hiking and trapezing. Constructed primarily of solid, hand-laid fiberglass for the main hull, the boat was engineered for rugged durability, sacrificing absolute weight savings in the vaka to ensure it could withstand the impacts of beaching and shallow-water sailing. The outriggers are lightweight and narrow, configured to slice through chops rather than ride over them, which minimizes drag but limits overall reserve buoyancy in the bows 5.
Sailing Performance & Handling
On the water, the Supernova is highly responsive and behaves like a lightweight dragster. Weighing in at just 203 pounds with a generous 129 square feet of sail area, the boat boasts an astronomical sail area-to-displacement ratio of 59.75. This configuration ensures near-instantaneous acceleration in light air, with the boat easily reaching double-digit speeds under its fractional sloop rig and rotating spar mast.
With a beam of 10.5 feet, the trimaran presents a highly stable platform. The capsize ratio of 7.15 underscores its wide, stable stance, which provides tremendous initial resistance to heeling. However, unlike a ballasted monohull, the Supernova relies entirely on its beam and dynamic lift for stability. When sailed at the limit in heavy air, the narrow amas can submerge and "dive," which can lead to rapid deceleration or pitchpoling if the crew does not quickly ease the sheets.
Helming the Supernova is a delicate exercise in momentum management. Because the main hull is narrow and the boat lacks the rotational inertia of a heavier vessel, tacking can be a challenge in a chop. Standard dinghy roll-tacking techniques do not apply; instead, helmsmen must carry speed into the turn and occasionally back the jib or mainsail to force the bow through the wind before shearing off on the new tack.
Known Issues & Triage
Decades after its production run, several structural issues have emerged in surviving Supernova models. The most critical failure point lies in the structural aluminum framework that connects the hulls. The mast step and the mounting brackets connecting the aluminum struts to the fiberglass hulls are subject to immense torsional and compression loads. Over time, stress fatigue can cause hairline fractures to develop around these weldments and bolt holes, occasionally resulting in catastrophic failures under high wind loads. Owners must inspect these brackets for stress cracks and corrosion, particularly where stainless steel fasteners meet the aluminum frame.
Additionally, the original daggerboard and rudder systems are common areas of wear. The factory daggerboard was often a basic, heavy, flat metal sheet that lacked an efficient foil profile, while the rudder head and marine plywood blade are highly prone to de-lamination and wood rot if left exposed to the elements 4. Leakage is also common around the main beam mounting receptacles on the central hull, where stress cracks can permit water intrusion into the bilge.
Modernization & Upgrades
For vintage multihull enthusiasts, the Supernova represents an appealing platform for performance modifications. One of the most common upgrades addresses the low volume of the factory outriggers 4. Creative owners have retrofitted larger, higher-volume custom amas—or extended the factory ones—to provide additional reserve buoyancy forward, significantly reducing the risk of burying the bows in a blow.
Rigging updates are also popular. Replacing the original heavy metal daggerboard with a modern, custom-molded carbon fiber or composite daggerboard dramatically improves both lift and pointing ability while reducing overall weight 4. Structural reinforcements around the mast step and the crossbeam mounting points using carbon fiber or Kevlar-thickened epoxy paste are highly recommended to prevent stress fractures. Finally, updating the original running rigging to high-modulus Dyneema lines and optimizing the jib sheeting tracks makes the rotating spar rig far easier to trim from the cockpit.
The Verdict 6
The Supernova is a fascinating, historically significant pocket trimaran that offers a unique blend of vintage sailing thrill and relative safety. While it cannot match the raw speed or structural refinement of modern, high-volume production trimarans like the Weta, it provides an exceptionally comfortable, seated sailing experience that makes high-speed multihull sailing accessible to those who prefer not to spend their day on a wet trampoline. For the sailor willing to execute a few structural modernizations and inspect its aluminum frame, it remains a rare, eye-catching, and rewarding classic beach multihull.
- Extremely fast and responsive in light to moderate air due to an impressive sail area-to-displacement ratio
- More comfortable and secure than traditional beach catamarans thanks to its dedicated seated cockpit
- Disassembles easily for effortless trailer transport or car-topping
- Easily righted by a single sailor in the event of a capsize
- Rotating mast setup optimizes sail shape and efficiency across different points of sail
- Slender, low-volume outriggers are prone to burying their bows in heavy air and chop
- Critical structural connections in the aluminum framework are prone to stress cracking and fatigue
- Narrow hulls make tacking difficult without specific, deliberate boat-handling techniques
- Factory daggerboard is heavy and inefficient compared to modern composite foils
- Scarcity of replacement parts requires custom fabrication for repairs and upgrades
