Luxury Yachts: AC45F - The Ultimate Naval Marvels
The America's Cup, the world's most prestigious sailing competition, has seen the introduction of two groundbreaking yachts in recent years: the AC45F and the AC75. While both are cutting-edge racing vessels, they differ significantly in design, technology, and performance.
AC45F Foiling Catamaran (Used in the 2016 America's Cup World Series)
The AC45F, a 45-foot (13.7 m) foiling catamaran, was a key component in the America's Cup World Series leading up to the 2017 event in Bermuda. Its twin hulls, made from carbon fiber composites, were fully equipped with L-shaped daggerboards and T-shaped rudder foils, allowing it to hydrofoil and lift the entire boat out of the water, reducing drag and increasing speed.
The AC45F's carbon fiber wing sail, standing approximately 67 feet (20.4 m) tall, provided ample power. The boat was typically operated by a crew of 5-6 sailors, with a displacement of approximately 1,250 kg (2,755 lbs). With a length overall (LOA) of 45 feet (13.7 meters) and a beam of about 24 feet (7.3 meters), the AC45F was capable of reaching speeds of up to 40+ knots (46+ mph, 74+ km/h) under foiling conditions.
AC75 Foiling Monohull (Used in the 2021 and 2024 America's Cup)
The AC75, a 75-foot (22.9 m) foiling monohull, made its debut in the 2021 and 2024 America's Cup events. Its high-tech carbon fiber construction, coupled with a canting foil system on each side, allows the hull to lift out of the water for foiling, significantly reducing wetted surface area and increasing speed.
The AC75's sailplan includes a rigid carbon fiber wing sail approximately 28 meters (92 feet) tall, one of the tallest sails ever used, as well as a large soft mainsail and headsails for off-wind conditions. With a crew of typically 11 sailors and a displacement of approximately 6,500 kg (14,300 lbs), the AC75 is a testament to the peak of sailing technology in terms of speed, complexity, and innovation.
Comparison Summary
| Aspect | AC45F | AC75 | |--------------------|------------------------------------|-----------------------------------| | Type | 45' foiling carbon fiber catamaran| 75' foiling carbon fiber monohull | | Crew Size | 5-6 | 11 | | Hull Form | Twin hulls | Single hull with foils | | Foiling System | L-shaped daggerboards and rudder foils | Large canting T-foil daggerboards | | Sail | Rigid wing sail (~67') | Rigid wing sail (~92') + soft sails | | Displacement | ~1,250 kg | ~6,500 kg | | Beam | ~24 feet (wide for stability) | ~5 meters (narrow, uses foils for stability) | | Speed | ~40+ knots | 50+ knots | | Purpose | Training and World Series racing | Main Cup racing with advanced tactics | | Technology Level| Early foiling tech platform | Advanced, highly complex engineering |
Summary of Advancements from AC45F to AC75:
The shift from the AC45F's catamaran concept to the AC75's monohull design pushed innovation to new limits, challenging crew tactics, single hull dynamics, and stability. The larger wing sail and overall bigger size increased power, requiring more sailors and more complex controls. The canting foil system on the AC75 allows the boat to fly more stably and faster in a monohull setup. The speed and complexity of the AC75 are significantly higher, pushing competitive sailing technology to near limits.
Freddie Carr, a seasoned sailor who has been part of various America's Cup teams, including Ainslie's BAR Racing, Team Origin, GBR Challenge, and INEOS Britannia, which won the Louis Vuitton Cup, has nominated the AC45F catamaran as one of the coolest and most innovative yachts of recent times. Carr stated that he has never felt more vulnerable in his life on a boat while sailing the AC45F, reflecting the adrenaline-pumping nature of the vessel.
The AC45F, despite being human-powered, was still able to foil and do stadium racing, requiring a skilled sailor to operate. The AC45F has an adrenaline factor of 90%.
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Sports enthusiasts might appreciate the evolution of the yachts used in the America's Cup, with the AC45F and AC75 showcasing significant advancements in sailing technology. While the AC45F, a 45-foot foiling catamaran, was a key component in the lead-up to the 2017 event, the AC75, a 75-foot foiling monohull, made its debut in the 2021 and 2024America's Cup. The shift from the AC45F's catamaran concept to the AC75's monohull design pushed innovation to new limits, challenging crew tactics and single hull dynamics. Sailors like Freddie Carr, a seasoned America's Cup racer, have praised the AC45F as one of the coolest and most innovative yachts of recent times, despite its adrenaline-pumping nature.
