The CANT Z.501 Gabbiano (Italian: Gull) was a high-wing central-hull flying boat, with two outboard floats. It was powered by a single engine installed in the middle of the main-plane and had a crew of 4-5 men. It served with the Italian Regia Aeronautica during World War II, as a reconnaissance aeroplane. During its debut in 1934, it set a world distance record. It was obsolete by 1940, but was still used throughout World War II, suffering many losses. A few remained in service until 1949.
Generally, the Z.501 had a mixed reputation. It was pleasant to fly, having low wing loading and good performance (when it was first introduced). It was quite reliable despite having only one liquid-cooled engine. However, there were problems with the durability of the wooden fuselage, particularly the aircraft built during the war. Its seafaring qualities were poor and the aircraft was susceptible to bad weather conditions. The fuselage would often break up in rough seas. Another problem was the engine nacelle: if the aircraft landed heavily the propeller could crash down into the cockpit. aircraft was used in the reconnaissance role thanks to its long endurance, but it was very vulnerable to enemy fighters or even bombers. Perhaps its only air victory was in the Aegean, when a fighter stalled while chasing a Z.501. The aircraft was more often relegated to second-line duties. Sometimes, with well-trained crews, it was able to attack submarines, damaging several of them (perhaps six in total) and contributing to the destruction of two others. The aircraft had no advanced detection systems, only depth charges.
Generally the aircraft's main task was search and rescue missions, and perhaps because of this it was called Mammaiuto(which means "Mamma help me!" in Italian). Another theory is that it earned the nickname because it was helpless against enemy aircraft. Even its sea capabilities were poor, and often the Z.501 needed to be helped by ships. As for its flying qualities, it was too slow, unmanoeuvrable, and under-armed to put up a defence against enemy fighters. As a result, many were shot down.