As part of the program of modernization and expansion which had begun after the Ethiopian war, the Regia Aeronautica sought the construction of a group of heavy four-engine bombers. A ministerial contest was published and the Cant Z 1014 was declared the winning bidder. Five prototypes were to be built, but for financial reasons, the production never came its way. The project was taken over by Piaggio, which had classified second in the contest with the offering of its P 108 at a cost of 50% less than those of the Cant Z 1014. The first prototype was completed in October 1939 but, because of an accident, it could not be transferred to Guidonia for tests and evaluation until the following year. The four-engine Piaggio was a very advanced aircraft with an elegant line, a structure entirely in metal, and ample windows. The engines were four 1,350-hp double radial eighteen cylinders P XII RC45 which allowed a maximum speed of 420 km/h. Particular attention was dedicated to the defensive armament with six 12,7 mm machine guns, four of which were mounted in two electrically controlled turrets set on the back of the engines and remotely controlled by the gunners; a solution which was decidedly avant-garde for the period.
After the evaluation period, the 274° squadron BGR (bombardamento a grande raggio) was based in Pisa and equipped with the first Ps 108s. During one of the training missions Captain Bruno Mussolini, son of the Duce, perished. The first operational mission took place in June of 1942. Subsequently, the squadron moved to Sardinia with the few remaining Ps 108s where it operated in actions against Gibraltar. Thereafter, following the Allied landing in Africa, it operated against naval convoy and the Algerian harbors. The P 108, the only Italian strategic bomber of World War II, was a structurally sound machine with good flight characteristics, but tormented by continuous problems with the engines, which never allowed for its full operational employment.