Z.501, Grupo 62 Aviacion Legionaria
Pollensa, Spain, 1939.
Pollensa, Spain, 1939.
Z.501, Squadriglie da Ricognizione Marittima
The Z.501 single-engined reconnaissance bomber flying boat was the first project of the new staff. Built in 1934, the Z.501 immediately gained prestige for Italy with a non-stop seaplane distance record of 2560 miles from Monfalcone to Massawa, Eritrea, in October of the same year. In 1935, after the French had exceeded the distance, the Z.501 flew 3080 miles non-stop from Monfalcone to Berbera, British Somaliland, regaining the record. On both flights the pilot was Mario Stoppani, chief pilot for Cant. This was an auspicious start for the Z.501, which in 1936 began a long career of service with the Regia Aeronautica. The flying boat was still in limited use at the end of the Second World War, in spite of its total obsolescence.
With an extensively-braced wing and float structure, the Z.501 presented a somewhat ungainly appearance that contrasted with its beautifully-streamlined hull. A familiar sight along Italian coasts for ten years, the Z.501 earned the affectionate nickname Mammaiuto (literally, "Mamma, help''') from the reaction of Italian children seeing it for the first time. The more ordinary name Gabbiano (Seagull) was also applied to the flying boat. Employing a 900 h.p. Isotta-Fraschini Asso XI R2C 15 twelve-cylinder liquid-cooled engine mounted in the wing, the Z.501 was built almost entirely of wood, with fabric-covered wing and tail surfaces. The hull contained two gun positions in the bow and aft of the wing; a third position was located in the engine nacelle above the wing. All three posts fitted single 7.7-mm. weapons. Bombs were carried under the wings in racks attached to the bracing struts. The load was normally two 550-lb. bombs, or four 352-lb., 220-lb., or 110-lb. bombs. Early models of the Z.501 employed two-bladed wooden airscrews, later replaced by the three-bladed metal type. The nose gun was omitted from some later models. Otherwise, the Z.501 underwent little change during its career.
In 1937-38 Rumania purchased a number of Z.501's to equip a coastal defense and naval cooperation group. Some of the Italian flying boats saw action in the Spanish Civil War.
When Italy entered the Second World War on June 10, 1940, the Z.501 equipped seventeen Squadriglie and four Sezioni, as follows: the 141a-148a , 171a , and 182a-189a Squadriglie da Ricognizione Marittima, and 1a, 3a-5a Sezioni Costiere; based on the Adriatic and Tyrrhenian Seas, Sardinia, Sicily, and smaller Italian islands. Of the 202 aircraft available, approximately 109 were in first-line operation. In spite of its long-range capabilities, the Z.501 was slow and vulnerable. Nevertheless, it served with the Regia Aeronautica until the Armistice, and continued with both the Allied Co-Belligerent Air Force and the Fascist Aviazione della RSI (Repubblica Sociale Italiana) until the end of fighting in Italy.
Performance of the Z.501 included a maximum speed of 171 m.p.h. at 8200 ft. and a cruising speed of 149 m.p.h. at 6560 ft. Climb to 13,120 ft. required 16 minutes. Normal cruising range with full military load was 621 miles, while maximum range was 1490 miles. Span was 73 ft. 10 in., length 46 ft. 11 in., height 14 ft. 6 in., and wing area 667.4 sq. ft. Empty the Z.501 weighed 8470 lb; with the normal load the weight was 13,090 lb., although the maximum figure was 15,510 lb.