and two others, fitted with a special metal three-blade propeller, and other modifications. On 19–20 May 1934, the modified Z.501 established a new seaplane distance record of 4,130 km (2,570 mi), by flying from Monfalcone to Massawa, in Eritrea, in 26 hours and 35 minutes. This distance record was lost to a French aircraft that flew 4,335 km (2,694 mi) on 23 June the same year, so another record flight was made on 16 July. The plan was to fly to Djibouti, a distance of 4,700 km (2,900 mi), but instead the aircraft flew 4,930 km (3,060 mi) to Berbera, Somaliland, in 25 hours. Military service Z.501's were used for search-and-rescue missions and anti-submarine patrols. The Z.501 was put into service with some modifications, including; turrets for the machine guns, and some reinforcement of the airframe that increased the overall weight by 500 kg (1,100 lb). The more powerful 656 kW (880 hp) Isotta Fraschini Asso XI.RC engine was fitted, but even with an additional 97 kW (130 hp), the maximum speed dropped to 245 km/h (152 mph), cruise speed to 200 km/h (120 mph), and range to 2,400 km (1,500 mi). The first units equipped were No.141 Sqn., Eritrea, No.83 Group, Augusta, No.85, Elmas, and No.62, Spain (for operations). By the time Italy entered World War II on 10 June 1940, 202 aircraft were in service in 15 squadrons. They were used by 20 Sqn. and patrolled the Mediterranean, as well as performing air-sea rescue operations. During the short campaign against France, seven Z.501s were destroyed by a French attack on their base in Sardinia. Another crashed the next day. In July, encounters with Royal Navy Fleet Air Arm fighters and accidents claimed many Z.501s, with a total of 11 destroyed in action, while the number that were operational dropped to 77. The Z.501 operated in all theatres and 62 aircraft were lost in 1940, leaving 126, of which only 87 were operational. New orders were placed with the manufacturer Aeronautica Sicula. At the end of 1941, there were Z.501s in 15 of the 27 squadrons dedicated to naval reconnaissance. During the year the number of operational aircraft increased to an average of 100, rising six months later to 108 in 11 squadrons.They were responsible, in collaboration with Italian ships, for the destruction of and damaged three other submarines. They were able to carry up to four bombs; either