The Piaggio P.50 was an experimental four-engined heavy bomber prototype developed in Italy during the mid-1930s. Designed as a long-range asset for the Regia Aeronautica, the aircraft represented one of the earliest attempts by Italy to produce a true heavy bomber, a class of aircraft that was rare in the country at the time. The project is widely recognized as the first aircraft designed by Giovanni Casiraghi, an engineer who would later lead the development of the Piaggio P.108.
Production was limited to three prototype airframes. The P.50-I variant saw two prototypes built: the first (MM369) flew in 1937, followed by a second (MM370) in 1938. The P.50-I featured a distinctive shoulder-wing monoplane design with a single large tail fin and rudder. Its most notable technical feature was a tandem tractor-pusher engine arrangement; four 730 hp Isotta-Fraschini XI RC 12-cylinder V piston engines were mounted in pairs on the wings, with each pair driving one tractor and one pusher three-bladed propeller. This configuration was intended to reduce drag while maintaining high power. The P.50-I was equipped with three 12.7 mm machine gun positions, including a nose turret.
Evolution of the design led to the P.50-II (MM371), which first flew on February 24, 1938. This version abandoned the tandem layout in favor of a conventional four-engine tractor configuration, utilizing four 1,000 hp Piaggio P.XI RC.40 radial engines. The P.50-II also saw an increase in defensive armament to five 12.7 mm machine guns. These prototypes were manufactured by Piaggio at its aircraft works in Liguria, with flight testing conducted at Malpensa airfield.
Despite the technical progress, the P.50 never entered series production. Although the Regia Aeronautica reportedly requested 12 aircraft, the program was cancelled a few months later, and the prototypes were abandoned. Consequently, the P.50 never entered military or civil service and saw no combat during World War II. Its primary legacy lies in its role as a technological stepping-stone; the engineering experience gained from the P.50's development was directly applied to the creation of the Piaggio P.108, Italy's only operational four-engined heavy bomber of the war.