CANT Z.501

Infobox Aircraft
name=Z.501 Gabbiano


caption=CANT Z.501 on the shore with beaching gear. Note the closed position in the nose, the pilot's cockpit just under the propeller, the engine nacelle was also used as a machine gun position.
type=Patrol aircraft
manufacturer=Cantiere Navali Triestino
designer=Filippo Zappata
first flight=1934
introduced=
retired=1950
status=
primary user=Regia Aeronautica
more users=Aeronautica Nazionale Repubblicana
Italian Co-Belligerent Air Force
produced=
number built=>200
unit cost=
variants with their own articles=The CANT Z.501 "Gabbiano" (Italian: "Gull") was a single engine flying boat that served with the Italian Regia Aeronautica during World War II. It had a crew of four or five and was used mainly for reconnaissance. Initially a successful aircraft, the holder of two world records for long-distance flight, it was obsolete by 1940, but was still used throughout World War II, suffering many losses. The last aircraft was retired in 1950.

Development

Filippo Zappata was one of the foremost Italian aircraft designers. He worked for Cantieri Navali Trieste (CANT), for some years, but went to France in 1927 to work for Blériot. He returned to Italy at the prompting of Italo Balbo and resumed work at CANT on a series of new aircraft. The first of these was the Z.501, designed to replace the Savoia-Marchetti S.78. The prototype Z.501, was first flown in 1934 by test pilot Mario StoppaniMarcon, Tullio, "Il CANT Z.501 Gabbiano", Storia Militare Magazione, Albertelli editor, Parma, November 1995, pp 10-21 it icon] .

Design

The aircraft had a very slim fuselage, a high parasol wing and a single wing-mounted engine nacelle. In the prototype a 750 hp inline Isotta-Fraschini Asso engine was fitted, with an annular radiator that resembled a radial engine (it had no liquid cooling). The engine nacelle was extended to carry a rear-facing machine gun, while other guns were mounted in the centre fuselage and nose. All were 7.7 mm Breda-SAFAT. Bombs up to 640 kg (4 x 160 kg) were carried under the wings.

The aerodynamic low-drag design was typical of Zapata-designed aircraft, as was the wooden construction. Overall, the aircraft was similar to the Consolidated Catalina, though this aircraft had two engines and was larger.

Record flights

The production aircraft had an endurance of 12 hours. However,the record-breaking version, as was quite common at the time (mainly due to the low fuel consumption of the piston engine), greatly exceeded this. The USA had established a new endurance record of 3,860 km; a Z.501 with the civilian registration "I-AGIL" was used to re-take the record in accordance with Mussolini's wishes. It was manned by Stoppani 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 (2,566 miles), by flying from Monfalcone to Massawa, in Eritrea, in 26 hours and 35 minutesJackson, Robert, "The Encyclopedia of Military Aircraft", Paragon, 2002. ISBN 0-75258-130-9] . 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 (2,921 mi), but instead the aircraft flew 4,930 km (3,064 mi) to Berbera, Somaliland, in 25 hours.

Military service

Production of the Z.501 began in 1935 with 24 aircraft ordered from CANT, and 30 from Aereonautica Sicula, a company in Palermo. Registration numbers started with MM.35168.

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. The more powerful 880 hp Isotta-Fraschini Asso XI RC engine was fitted, but even with an additional 130 hp, the maximum speed dropped to 245 km/h, cruise speed to 200 km/h, and range to 2,400 km..

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.501's 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 only 126, of which only 87 were operational. New orders were placed with the manufacturer Aereonautica Sicula.

Z.501's were used for search-and-rescue missions and anti-submarine patrols. They were responsible, in collaboration with Italian ships, for the destruction of HM "Union" and damaged three other submarines. But their effectiveness was limited by their bombload of only four 50 kg or two 160 kg bombs.

At the end of 1941 there were Z.501's in 15 of the 27 squadrons dedicated to naval reconnaissance. Strangely, the number of operational aircraft increased to an average of 100, rising six months later to 108 in 11 squadrons, probably due to the arrival of new aircraft..

By the end of 1942 there were 199 aircraft in service, 88 of which were operational. Maritime reconnaissance had at that time 290 aircraft in total.

By September 1943 there were still 240 aircraft assigned to maritime reconnaissance: only 84 were Z.501's, in three squadrons, and another 11 (mixed), out of 20 in total. Only around forty aircraft were operational. The total production, 218 by CANT and 236 by Aereonautica Sicula, was in fact less, as a dozen aircraft were captured incomplete after the invasion of Sicily. Later Aereonautica Sicula repaired many of the ICAF aircraft. Some modifications were adopted during production, such as the removal of the nose machine-gun, replaced by an enclosed fairing.

Some Z.501s were supplied to Romania and to the Nationalists during the Spanish Civil War. Following the Italy's surrender in 1943, a few of these flying boats continued to operate with both the Axis Aeronautica Nazionale Repubblicana and the Allied Italian Co-Belligerent Air Force.

After the armistice, several flew to southern Italy, including the 9 aircraft of 149 Sqn with 80 persons aboard. In October, there were 16 aircraft operational in southern Italy, which dropped to 10 by May 1945. The squadrons involved were No's 141, 147, and 183. After the war 183 Sqn. was based at Elmas with four Z.501s, and these were scrapped in 1950.

Combat performances

Generally the Z.501 had a mixed reputation. It was pleasant to fly, having low wing loading and good performance. 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.

The aircraft was used in the reconnaissance role thanks to its long endurance, but it was very vulnerable to enemy fighters or even bombers. Perhaps the 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 as 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 "Mammaiut" (another theory is that because it was helpless against enemy aircraft). Even its sea capabilities were not good 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.

Military operators

;flagicon|Italy|1861-state Italy:;ESP;ROM

pecifications (Z.501)

aircraft specifications
plane or copter?=plane
jet or prop?=prop
ref=The Encyclopedia of Weapons of World War IIref WW2 | | ]
crew=4-5
length main=14.30 m
length alt=46 ft 11 in
span main=22.50 m
span alt=73 ft 9¾ in
height main=4.40 m
height alt=14 ft 6 in
area main=62 m²
area alt=670 ft²
empty weight main=3,850 kg
empty weight alt=8,490 lb
loaded weight main=
loaded weight alt=
max takeoff weight main=7,050 kg
max takeoff weight alt=15,300 lb
engine (prop)=Isotta Fraschini Asso XI RC2C.15
type of prop=liquid-cooled V12 engine
number of props=1
power main=880 hp
power alt=671 kW
max speed main=275 km/h
max speed alt=148 knots, 170 mph
cruise speed main=
cruise speed alt=
never exceed speed main=
never exceed speed alt=
stall speed main=
stall speed alt=
range main=2,400 km
range alt=1,300 nm, 1,500 mi
ceiling main=7,000 m
ceiling alt=23,000 ft
climb rate main=
climb rate alt=
loading main=
loading alt=
power/mass main=
power/mass alt=
guns=3× 7.7 mm (0.303 in) Breda-SAFAT machine guns (initially Vickers), but many had only two when nose position was removed
bombs=640 kg (1,400 lb) carried externally

Notes

References

* Jackson, Robert, "The Encyclopedia of Military Aircraft", Paragon, 2002. ISBN 0-75258-130-9
*Marcon, Tullio, "Il CANT Z.501 Gabbiano", Storia Militare Magazione, Albertelli editor, Parma, November 1995, pp 10-21 (Italian)
*Bishop, Chris (ed.) 1998, "The Encyclopedia of Weapons of World War II", Barnes & Noble, New York. ISBN 0-7607-1022-8

ee also

aircontent
related=
similar aircraft=
* PBY Catalina
sequence= taken out of template
see also=
lists=
* List of seaplanes and flying boats
* List of aircraft of Italy, World War II