CANT Z.1007

The Cant Z.1007 Alcione (Kingfisher), nicknamed "the flying barn door" by its air crews because of its flying characteristics, was a three-engined medium bomber used by the Italian Regia Aeronautica, Italian Co-Belligerent Air Force, Aeronautica Nazionale Repubblicana and Luftwaffe during World War II.

Design and development

Background

The Cant Z.1007 was developed from the Cant Z.506 seaplane, an aircraft that had established many world records in the late 1930s. It was a land-based version and incorporated many improvements, especially on the powerplant. Filippo Zapata, the father of many aerodynamically streamlined aircraft, designed the Z.506. As a land-based bomber, it was better than other machines already in service with the Regia Aeronautica and therefore, a first series of 32 were ordered, and designated Z.1007 Asso, after its 619 kW (830 hp) Isotta-Fraschini Asso inline engines.

Engine

The Asso engines had annular radiators so their profile was similar to radial engines that would be fitted later. The first prototype flew in March 1937, but lacked an improvement in performance compared to the Savoia-Marchetti SM.79 Sparviero, even with 430 km/h (270 mph). Improvements were made with Piaggio P.XI engines, capable of 750 kW (1,000 hp) and the Z.1007bis went into production in 1939 displaying more capability than all previous Italian bombers.

Configuration and problems

The Z.1007 had a standard monoplane configuration, with a low-set wing, single tail, retractable undercarriage, and a crew of five or six. It had a totally wooden structure, and a very clean shape that was much more aerodynamic than the competing SM.79. The Z.1007 had three Piaggio P.XI engines (a derivative of the French Gnome-Rhône 14K) of 750 kW (1,000 hp) each, with one engine in the nose and two in the wings. The trimotor design was a common feature of Italian aircraft of World War II. The aircraft had a slim fuselage as the two pilots sat in tandem rather than side-by-side as in most bombers of the period. Visibility was good and the aircraft was almost a "three-engine fighter" with a very narrow fuselage. This reduced drag, but also worsened the task of the two pilots. The aft pilot had reduced instruments and visibility, and so had difficulty flying and landing the machine if needed; he was almost an 'emergency' pilot. Like most trimotor Italian aircraft of the period the Z.1007 suffered from poor defensive armament, poor engine reliability, and poor power to weight ratio due to low powered engines. The Z.1007 also suffered longitudinal stability problems that were partly rectified later by the adoption of a twin tail arrangement. The Z.1007's wooden structure suffered cracks, separations, and surface delamination due to the difficult climatic conditions in North Africa and Russia. The surface delamination and deformation greatly added to the aircraft drag.Template:Citation needed A total of 660 Alciones were built.

Armament

The Z.1007 had a defensive armament of four machine guns: two 12.7 mm (.5 in) and two 7.7 mm (.303 in). The main defensive weapon was an Isotta-Fraschini Scotti or 12.7 mm (.5 in) Breda-SAFAT machine gun in a Caproni-Lanciani Delta manually-powered, or a Breda electrically-powered dorsal turret. The turret had a 360° field of fire and 0-70° of elevation, with 350 rounds. The 12.7 mm (.5 in) Breda was a standard weapon for Italian bombers and the field of fire was improved by the double-tail configuration on later models. Another 12.7 mm (.5 in) was in the ventral position behind the bomb bay, with a field of fire restricted to the lower rear quadrant of the aircraft. There were also two waist position 7.7 mm (.303 in) Breda machine guns, with 500 rpg. Only one of the waist guns could be used at a time since the gunner for this position manned both guns. Allied reports stated that Armour (probably referring to later, better armoured versions) was better than usual for an Italian bomber, with a large (.76 m/2 ft 6 in × 1.1 m/3 ft 6 in, plus a small head protection one of .36 m/14 in × .20 m/8 in) 8 mm (.31 in) curved plate for rear protection of dorsal gunner (rotating with his turret), 5 mm (.20 in) for side gunners with other 6 mm (.24 in) all around the machine guns, and 6 mm (.24 in) for ventral machine gun position, this meant that all defensive positions were reasonably protected against enemy fire. The pilots were protected, even if an armoured windscreen was not available, with 5 mm (.20 in) roof and lateral, 6 mm (.24 in) around the seats, 5 mm (.20 in) over their heads, and a 6 mm (.24 in) armoured bulkhead behind them.

The Z.1007 had a horizontal bomb bay which could carry 1,200 kg (2,650 lb) of ordinance. Many other Italian aircraft had vertical bomb bays which not only limited accuracy, but also limited the size of bombs carried internally. There were also a pair of under-wing hard points which could carry up to 1,000 kg (2,200 lb) of bombs, giving the Z.1007 a potential 2,200 kg (4,900 lb) payload (to a maximum range of 640 km/400 mi), but the norm was 1,200 kg and 1,000 km range. The Z.1007's external hardpoints were a rarity in the bombers of the Regia Aereonautica. The Z.1007 could also carry two 454 mm (17.7 in), 800 kg (1,760 lb) torpedoes slung externally under the belly in an anti-shipping role, an option never used in service. The bombardier's nacelle was near the wings, just below the pilot. This improved the layout compared to the SM.79, that had the nacelle almost in the tail section, with the double task of machine-gun defence position.

Operational history

Battle of Britain

The Z.1007 saw action during the later stages of the Battle of Britain from November 1940 to January 1941. The Regia Aereonautica sent six Z.1007Bis of the 172nd Squadron to Belgium in the strategic reconnaissance role for the Corpo Aereo Italiano. Upon arrival in September the Italian command realized the Luftwaffe had already photographed nearly every inch of S.E. England and there was really nothing for them to do. They were used in force only once, on November 11, when five were used as a decoy (without bombs or guns) to draw RAF fighters away from the main Italian attack on a convoy and the port facilities around Harwich by 10 Fiat BR 20 bombers. The plan failed. No Z.1007's were lost over Britain, although one of the six originally sent was lost in September on the ferry flight to its base in Belgium.

Greco-Italian War

The Z.1007 first saw action in the Italian invasion of Greece in October 1940. The Z.1007 participated in the bombing campaign over Malta and in the campaigns in North Africa and on the Eastern Front. Although fast, these bombers were vulnerable when hit and prone to catch fire.

The service saw 47 Wing equipped with some of the first production aircraft at Ghedi. Only four were in service at 10 June 1940. The production was slow with 15 machines made every month at best. The first 34 machines, Z.1007 Asso, were used as trainers and later for weather recognissance. In 1943 there were still 16 available. A transformation with Delta engines was made to improve cost-effectiveness but only applied to one machine. With time the aircraft was used by different Wings like the 9th and substituted the SM.79 and BR.20.

Cant Z.1007 Asso replaced SM.81s in 16 Wing, 47 Wing had Z.1007Bis but operational readiness was only reached in August, when around 30 machines were sent to Sicily to attack Malta. Wings 16°, 12°, 35°, and 47° operated over Greece with some losses, among them one made by a PZL.24 manned by Ltn. Mitraxialexis. 175 reconnaissance squadron, and later 176th, were used in Africa. The British destroyer Template:HMS was sunk by an explosion caused by a Z.1007 bombing in 1941. 35 Wing was sent to Africa in the bombing role.

In 1942, Z.1007s were used by four groups and two wings in the Mediterranean theatre, in anti-ship role and against Malta, often escorted by Italian and German fighters.

In November 1942, there were eight groups equipped with 75 Z.1007s 75, with just 39 serviceable aircraft out of 150 bombers of all types.

During Italian and German efforts to stop "Pedestal" Convoy, en-route to Malta in August 1942, Sardinia-based Z.1007 Alciones, shadowed the convoy in between bombing raids and one Z.1007bis carried out a special mission, a first in the war, later copied by Allied air forces (John F. Kennedy's elder brother, Joseph P. Kennedy Jr died during a similar mission).

General Ferdinando Raffaelli came up with the concept of packing a "SIAI Marchetti SM.79" bomber with explosives and a radio control device. As the Pedestal Convoy was under way off the Algerian coast on August 12, the SM.79 "Drone", a Z.1007bis guide plane and escort of five FIAT G.50 fighters flew out to intercept the ships. Once the SM.79's pilot had set his aircraft on a course toward the Allied ships, he bailed out leaving the Z.1007bis crew to guide the flying bomb the rest of the way by radio.

The radio, however, malfunctioned. With nothing to guide it, the SM.79-Drone cruised along until it ran out of fuel and crashed on Mount Klenchela, on the Algerian mainland.Template:Citation needed

Final deployment

In June 1943, the Z.1007s at Perugia, originally equipped with 30 machines, dropped to 19 with 13 serviceable in September. At the Armistice there were approximately 72 machines in service, with 40 of them sent to southern Italy. They were used as fast transports, with the ICAF proposing to use them as bombers in the Pacific theatre.

World War II problems and performances

The worst day for Z.1007s was 14 May 1944, when 88° Gruppo sent 12 Z.1007s carrying supplies to Tito's forces. Five were shot down and two damaged by German fighters, 26 Italian aviators were killed. From that day on, it was employed only at night for military purposes.Template:Citation needed

Z.1007ter was an improved version, that should have used Alfa 135 engines of 1,040 kW (1,400 hp). This version was dropped because of the advent of the Z.1018 and the unreliability of the engines. There was another -ter proposal with P.XI engines (858 kW/1,150 hp), and production was started in 1942, with a total of around 150 made. Test pilots were more impressed by this machine than the Z.1018, faster but with less power (because of the layout with only two P.XII engines), while the range was improved from 2,000 km (1,240 mi) to 2,250 km (1,400 mi) with 2,460 kg (5,420 lb) fuel and 900 kg (1,980 lb) bombs. So, while the Z.1018 had 2,013 kW (2,700 hp), already Z.1007Bis had 2,237 kW/3,000 hp (1,946 kW/2,610 hp at take off) and Z.1007ter 2,572 kW (3,450 hp).

Performances were improved with a max speed of 490 km/h (300 mph) at 6,150 m (20,180 ft) instead of 456 at 4,600 m (15,100 ft). Climbing to 3,000 m (9,800 ft) in 6 min 28 sec, and 5,000 m (16,400 ft) in 10 min 44 sec (Z.1007 bis in 12 min 42 sec, Z.1007 Asso in 14 min 34 sec). Armament and armour were also improved. The dorsal turret was a Breda model, flank weapons were replaced with 12.7 mm (.5 in). Ceiling was raised to 9,000 m (29,500 ft) from 8,400 m (27,600 ft).

Z.1007s were used mainly as night bombers and reconnaissance, they were also used for long range reconnaissance, with excellent results. Some, at least 20, were equipped with an auxiliary tank that gave 1,000 km (620 mi) extra endurance. Some were adapted for flare drops when day missions were too dangerous. One modification for photo missions had six robot machines in a ventral gondola plus another in the fuselage. The long range and the ceiling helped these aircraft to obtain good results until the Spitfires appeared on the Mediterranean theatre. They were also the first victims of P-40 Tomahawks over Alexandria.

Another development was the Z.1015, proposed as a record-breaking version of the Z.1007 in 1938 but not considered until 1942, when the Alfa 135s were substituted by Piaggio P.XII engines. It could reach a speed of 563 km/h (350 mph), thanks to a total of over 2,982 kW (4,000 hp) installed. It was tested successfully as a torpedo aircraft, but it was not used operationally and did not enter production.

The few Z.1007ter still flying after the Allied invasion of Sicily went on to fight with the Italian Social Republic, Italian Co-Belligerent Air Force and the Luftwaffe.

Operators

Template:Country data Croatia Independent State of Croatia

• Zrakoplovstvo Nezavisne Države Hrvatske

Template:Country data Germany

• Luftwaffe operated captured aircraft.

Template:Country data Italy

• Regia Aeronautica

Specifications (Z.1007bis)

Data from The Encyclopedia of Weapons of World War II

General characteristics

• Crew: 5
• Length: 18.35 m (60 ft 2.5 in)
• Wingspan: 24.80 m (81 ft 4.5 in)
• Height: 5.22 m (17 ft 1.5 in)
• Wing area: 70 m² (750 ft²)
• Empty weight: 9,396 kg (20,715 lb)
• Max takeoff weight: 13,621 kg (30,029 lb)
• Powerplant: 3× Piaggio P.XI RC.40 radial engines, 745 kW (1,000 hp) each

Performance

• Maximum speed: 458 km/h (245 kn, 285 mph)
• Cruise speed: 338 km/h (183 kn, 210 mph)
• Range: 1,795 km (969 nmi, 1,115 mi)
• Service ceiling: 7,500 m (25,000 ft)

Armament

• Guns:
  
  • 2 × 12.7 mm (0.5 in) Isotta-Fraschini Scotti or Breda-SAFAT machine guns
  • 2 × 7.7 mm (0.303 in) Breda-SAFAT machine guns
• Bombs:
  
  • 1,200 kg (2,645 lb) of bombs internally. 1,000 kg (2,200 lb) externally on underwing hardpoints. Or a combined load of 2,200 kg (4,900 lb) of bombs internally and on external hardpoints.
  • 2 × 450 mm (17.7 in) 800 kg (1,800 lb), torpedoes

See also

Designation sequence
taken out of template Related lists

• List of bomber aircraft
• List of military aircraft of Italy

References

• Garello, Gian Carlo, Il Cant 1007 Alcione, Storia militare n.20, May 1995, Albertelli edizioni speciali, Italy.
• Malizia, Nicola, L'armamento dei velivoli della Regia Aereonautica, Storia militare sept.1999.
• U.S. Intelligence Report, Tactical and Technical Trends, No. 25, 1943.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "CANT Z.1007".