AC40: A 40-Foot Foiling One-Design Derived from America’s Cup Technology

The AC40—a 40-foot, scaled-down foiling day-racer based on the 75-foot AC75 used in the 36th America’s Cup—is now available for private purchase. Designed by Emirates Team New Zealand and built by McConaghy Boats in Australia, the AC40 brings high-performance America’s Cup foiling technology into a one-design class aimed at competitive racing, training and development.

Design and Build

McConaghy Boats is producing the first AC40 hulls, which draw heavily on the research and geometry developed by Emirates Team New Zealand. The AC40’s hull form is inspired by New Zealand’s test boat for the 36th America’s Cup, Te Kahu, and references the defender’s AC75, Te Rehutai. That lineage carries over modern foil configurations and weight distribution strategies to ensure the smaller boat performs predictably at speed.

Foil Configuration and Sailing Characteristics

Like the AC75, the AC40 uses two large, weighted foils mounted on either side of the hull instead of a traditional fixed keel. The boat is engineered to foil on a single leeward foil with the windward foil raised clear of the water. This approach reduces drag and increases righting moment, enabling higher speeds and more efficient flight. An autopilot control system is integrated to help maintain stable flight regimes, improving safety and control while foiling.

Crew, Systems and Handling

The AC40 is a crewed boat sailed by four people: two helmsmen and two trimmers. Traditional human grinders have been replaced by battery-powered systems, reducing physical demands and allowing for more consistent power delivery to foil and sail systems. The headsails are self-tacking to simplify maneuvers and reduce workload, making transitions and close-quarters racing more manageable while preserving high-performance handling.

Performance Expectations

Performance projections for the AC40 underline its foiling pedigree. In light wind conditions the boat is expected to reach up to 26 knots upwind and around 30 knots downwind. Under a true wind speed of 20 knots, designers expect the AC40 to be capable of speeds up to approximately 39 knots upwind and as much as 44 knots downwind. Those figures reflect the benefits of the foil configuration, lightweight construction and optimized control systems.

Role in America’s Cup Campaigns and Racing

While the 37th America’s Cup will continue to use the AC75 platform—with an updated rule set for that event—the AC40 will serve multiple roles across the campaign cycle. Teams plan to use the AC40 for training, development work, and preliminary regattas where a one-design foiling class can provide consistent conditions for testing crew procedures, systems and tactics. Additionally, the organizers have introduced a Women’s America’s Cup contested in the AC40 class, a move that has sparked debate within the sailing community. Supporters view it as an opportunity to grow participation and develop talent in a dedicated foiling class; others have questioned the decision as part of the broader America’s Cup program structure.

Ownership and Support

The first AC40s are now in production by McConaghy Boats. Buyers will also have access to Emirates Team New Zealand’s simulator resources as part of the support offering, helping new owners and teams accelerate their learning curve and refine foiling techniques in a controlled environment. For those interested in ownership, production details, build timelines and options are available directly from McConaghy Boats—prospective purchasers should contact McConaghy Boats for the latest specifications, pricing and delivery information.

Summary

The AC40 translates top-tier America’s Cup foiling performance into a compact, one-design platform intended for competitive racing, team development and private ownership. With modern foil technology, battery-driven systems, self-tacking headsails, and an autopilot to assist stable flight, the AC40 offers an accessible yet high-performance foiling experience rooted in the design expertise of Emirates Team New Zealand and the build capabilities of McConaghy Boats.