Tempest (International) Information, Review, Specs

The story of the International Tempest begins in 1965 with its design by Ian Proctor, a figure well-regarded in small boat design. Proctor leveraged his extensive experience with high-performance development classes such as the International 14, Merlin Rocket, and National 12 to craft a boat that was both fast and manageable for a two-person crew. His design philosophy aimed for a vessel that was "well behaved in a variety of conditions" while allowing for a fair division of labor between the sailors. The Tempest was adopted as a World Sailing class in 1968, solidifying its position in international competition.

During this era, builders like Lanaverre were at the forefront of composite construction, pioneering the use of Glass Reinforced Plastic (GRP), or fiberglass. This transition from traditional wood to modern materials allowed for more consistent boat performance and facilitated the production of a strict one-design class. The International Tempest is built from a master set of molds under the supervision of World Sailing (formerly ISAF), ensuring that all boats are alike in hull, deck, keel, and other key components, thereby emphasizing sailor skill over equipment advantage. While Lanaverre's primary fame came from the ubiquitous 420 dinghy, their expertise in fiberglass construction made them a fitting builder for high-performance one-design classes like the Tempest during its early production years which began in 1965.

Sailing Performance and Handling

The International Tempest is engineered for speed and agility, characteristics clearly reflected in its performance ratios. With a Sail Area to Displacement Ratio (SA/Disp) of approximately 39.05, the Tempest boasts an extremely high power-to-weight ratio, suggesting exceptional performance in light air and the capacity for rapid acceleration. This high ratio is indicative of a boat designed to be lively and responsive, quickly converting even subtle wind shifts into forward motion.

Its Ballast to Displacement Ratio (Bal/Disp) stands at a significant 0.43, or 43.10%. This substantial ballast ratio contributes to the boat's remarkable stiffness and stability, allowing it to stand up to its considerable sail plan in stronger winds without excessive heeling. This stiffness is crucial for a high-performance keelboat, enabling the crew to efficiently transfer power from the sails into forward thrust.

Furthermore, the Tempest's Displacement to Length Ratio (Disp/LWL) is a remarkably low 56.98. This low figure places it firmly in the category of very light-displacement, performance-oriented vessels. Combined, these ratios describe a boat that is unequivocally a racing machine: lightweight, powerful, and stable. Anecdotal accounts from sailors consistently describe the Tempest's handling as "terrific," praising its ability to be "well behaved in a variety of conditions". Many in the small boat design community consider it among the fastest one-design keelboats in the world, capable of leaving many contemporary "sport" boats in its wake. Its responsive nature and ability to be sailed effectively by a two-person crew, even with a trapeze, underscore its reputation as a true thoroughbred on the racecourse.

Accommodations and Layout

As a dedicated two-person racing keelboat designed for Olympic competition, the International Tempest prioritizes performance above all else, which means interior accommodations are minimal to non-existent. The design focuses entirely on the efficiency of the racing platform, not on providing creature comforts or an interior living space. Therefore, the Tempest features no significant cabin, galley, or sleeping berths typical of cruising sailboats. Its layout is strictly geared towards sail handling, crew ergonomics during racing, and maximizing speed.