A truly remarkable design, the Piaggio P.7 or Piaggio-Pegna P.c.7 was built for the 1929 Schneider Trophy contest. A cantilever high-wing monoplane with long slender fuselage, it had twin hydrofoils instead of floats and was intended to float with the wing resting on the surface of the water. While water-borne it was to be driven by an ordinary marine propeller connected by a shaft and clutch to the rear of the 723kW Isotta Fraschini Special V.6 engine. Once sufficient speed had been attained to lift the aircraft on to the hydrofoils and the normal tractor propeller was clear of the water, this latter propeller would be clutched-in, the marine propeller disengaged, and a conventional take-off would follow.
In practice, problems with the respective clutches prevented the P.c.7 from ever taking off, and although water trials were conducted on Lake Garda by Dal Molin of the Italian Schneider team, the construction of a second aircraft was abandoned.
Engine: 1 x Isotta-Fraschini Special, 723kW
Max take-off weight: 1738 kg / 3832 lb
Wingspan: 6.76 m / 22 ft 2 in