Wood Framing

Frame Assembly

Wood Skin

Mechanical

Paint & Body

Detail & Trim

Finish

The ‘three-point’ hydroplane, devised in America during the late 1930s by Adolph and Arno Apel of New Jersey’s Ventnor Boat Works, truly revolutionized speedboat design. Elegantly simple, the Apel design divided the ‘step’ portion of the hull into two pontoon-like surfaces, or sponsons, with each on opposite sides of the boat. The boat’s propeller acted as the ‘third point’ in the equation. The tunnel between the sponsons trapped air to generate aerodynamic lift, with only the sponsons and propeller in direct contact with the water whilst the boat was at speed.

Italy’s premier speedboat racer was Achille Castoldi, a cousin of M.C. 72 designer Mario Castoldi and a highly talented driver and engineer in his own right.

Castoldi’s boat, dubbed ‘Arno XI’, was built to a three-point hydroplane design by Timossi Azzano’s Cantieri Timossi boatyard located on Lake Como. A beautiful example of form and function in equal parts, the hydroplane featured a solid wood-framed structure skinned by marine-grade plywood with a mahogany veneer, a strong separate metal sub-frame chassis to cope with the enormous power and the engine cover and cockpit exterior appropriately finished in Rosso Corsa.

Once completed, ‘Arno XI’ was shaken down at the Campione d’Italia races in January 1953, with Castoldi reaching an unofficial top speed of 124 mph, prior to attempting an officially sanctioned two-way run. Castoldi’s main competitor, Mario Verga, who received the full factory support of Alfa Romeo, went on to set a new 800 kg class speed record of 202.26 km/h (125.68  mph) with his Alfa Romeo 159-powered boat, ‘Laura’. Adding emphasis, Verga reset the record just two weeks later with a two-way top speed of 226.50 km/h (140.74).

Undaunted, Castoldi had the 4.5-litre Tipo 375 F1 V-12 engine rebuilt and highly modified, with official Ferrari support, including Stefano Meazza, Scuderia Ferrari’s chief race engineer who oversaw the engine preparations for Castoldi. This time, the already highly powerful Ferrari V-12 racing engine was tuned to operate on methanol, now allowing much higher engine compression, in conjunction with twin superchargers and twin four-choke carburettors, with power output now exceeding 600 bhp, representing a power increase of some 200 bhp over the original specification!

Once upgraded and readied for competition, Castoldi made his record attempt at Lake Iseo on the morning of 15 October 1953, with Alberto Ascari and Luigi Villoresi in attendance, clearly demonstrating Ferrari’s support of the project. Now, Castoldi finally achieved his objective, with ‘Arno XI’, by breaking the speed record in the 800 kg class with a two-way average speed in the flying kilometer of 241.708 km/h (150.19 mph). Later that day, Castoldi followed up with a new record in the 24 nautical mile event by achieving an average speed of 164.70 km/h (102.34 mph).

Read more about the Timossi-Ferrari at: http://www.rmauctions.com/lots/lot.cfm?lot_id=1049320