CANT Z.1018 Leone

CRDA

Industry	Aerospace
Founded	1930s
Headquarters	Italy
Products	Aircraft, including CANT Z.1018 Leone

Template:Multiple issues Template:Infobox aircraft

The CRDA CANT Z.1018 Leone (meaning Lion) was an Italian medium bomber developed during the early 1940s.

Design and development

In 1939, the Regia Aeronautica launched its ambitious R Plan, also called the 3,000 airplanes initiative, aimed at rapidly expanding its fleet with up-to-date aircraft. Having been engaged in conflicts across two continents, the air force faced dwindling resources and equipment that lagged behind technological progress.

As part of this initiative, a competition for a new medium bomber was announced in the same year. CRDA entered its Z.1015 model, essentially an all-metal adaptation of the wooden-framed three-engine Z.1007, which had first flown in 1937 but was yet to be adopted for service by 1939.

The Regia Aeronautica requested that designer Zappata strengthen his proposal by increasing the aircraft’s ultimate structural load factor from 7.0 to 10.0. Recognizing this would necessitate extensive redesign and add weight, Zappata instead suggested a fresh two-engine design, the Z.1018.

While the three engines of the Z.1007 produced a combined output of 2,237 kW (3,000 hp), the proposed twin Alfa Romeo 135 RC.32 engines on the Z.1018 would deliver 2,088 kW (2,800 hp) together. This arrangement promised similar performance to the Z.1015 but with simpler construction, potentially lower weight, and easier maintenance.

Zappata outlined three versions based on varying wing configurations:

• A high-speed bomber featuring a wing area of 50 m² (532 ft²);
• A bomber with increased payload capacity using a wing of 63 m² (678 ft²);
• A high-altitude bomber equipped with a wing spanning 72 m² (775 ft²).

This new design also enabled carriage of an internal torpedo, which was unfeasible with the Z.1015’s fuselage layout.

CANT proposed a seaplane variant named Z.514, intended to utilize floats from the Z.506—noting that their floatplanes were designated in the 500 series while landplanes used the 1000 series.Template:Fix/category

On 23 February 1939, authorization was granted for production of thirty-two Z.1018 units, with a revised ultimate load factor requirement lowered to 9.0. Additionally, construction of a prototype was mandated, and deliveries were to commence before year-end—a notably aggressive timetable that CRDA found unrealistic due to pending engine certification and absence of counter-rotating variants.

Approval for building the initial prototype came on 7 April 1939. By July that year, Regia requested a shift from radial engines to the water-cooled inline Daimler-Benz DB 601 engines.

The finalized Leone I featured two engines powering a medium bomber frame with a single vertical stabilizer, retractable landing gear, and an all-metal structure composed primarily of duralumin with light alloy skinning. The slim fuselage was aerodynamically shaped and accommodated four to five crew members arranged in tandem cockpits—only the lead pilot had full flight controls while the co-pilot had limited instrumentation and visibility.

Its straight-tapered low wings had rounded tips and incorporated two main spars; metal sheeting covered the forward sections while fabric covered rear portions. Despite efforts to minimize weight, prototype empty mass approximated that of the three-engine Z.1007.

The prototype’s powerplants were Piaggio P.XII-RC.35 air-cooled radial engines with eighteen cylinders arranged in two rows, producing 895 kW (1,200 hp) at takeoff and up to 1,007 kW (1,350 hp) at an altitude of 3,500 m (11,480 ft), running at 2,050 rpm. These weighed approximately 930 kg dry (940 kg including oil) and operated on 87 octane fuel. Propulsion was provided by three-blade variable-pitch metal propellers manufactured by Alfa Romeo.

With these engines, CANT engineers projected a maximum speed of around 524 km/h (326 mph) at an altitude of approximately 4,500 m (14,764 ft). Takeoff distance was estimated at about 354 m (1,160 ft), landing required roughly 462 m (1,518 ft), and climb performance included reaching 4,000 m (13,120 ft) in seven minutes and thirty-two seconds (and six minutes forty seconds more to reach six thousand meters).

Fuel capacity was designed at approximately 3,300 liters (870 US gallons) housed within self-sealing tanks installed in each wing. An optional auxiliary tank holding an additional 500 liters (130 US gallons) could be fitted in the rear fuselage area. Endurance estimates suggested about three hours’ flight time at maximum cruise speed for a range near 1,335 kilometers (830 miles). Although data for economical cruise speeds are unavailable for this model, comparable aircraft such as the Savoia-Marchetti SM.79 Sparviero demonstrated improved ranges when flying slower.

Armament plans included carrying twelve bombs weighing around one hundred kilograms each within an internal bomb bay. Wing hardpoints were designed to support external loads up to one thousand kilograms apiece—allowing two such ordnance units externally given the calculated payload margin of approximately two thousand seven hundred kilograms (5,950 pounds). For perspective, contemporaries like the Fiat BR.20 and Savoia-Marchetti SM.79 could handle payloads near three thousand six hundred kilograms (7,940 pounds), while the CANT Z.1007 exceeded four thousand kilograms (8,820 pounds).

This payload calculation indicated that takeoff with full fuel tanks and crew (around two thousand eight hundred kilograms or six thousand one hundred seventy pounds) left little room for weapons load—suggesting that prototype testing never fully assessed maximum weapons capacity.

Defensive firepower comprised four machine guns:

• A Breda-SAFAT caliber .50 inch (12.7 mm) mounted within a Caproni-Lanciani belly turret;
• A Scotti .50 inch (12.7 mm) gun positioned in an upper turret;
• Two Breda-SAFAT .303 inch (7.7 mm) guns installed on each side of the fuselage.

Additionally, a fixed Breda-SAFAT .303 inch gun was mounted on the right wing for ground attack or forward defense roles. Ammunition allotments were planned as follows: three hundred fifty rounds per .50 caliber gun and five hundred rounds per .303 caliber gun. Installation challenges with the upper turret resulted in it being fixed partially retracted—limiting its firing arc.

These armaments increased overall weight and negatively influenced flight performance; furthermore, retrospectively equipping a fast bomber with a fixed forward-firing gun seems unnecessary.

Other onboard equipment included oxygen supplies, radio systems, fire extinguishers, and photographic apparatus.

The prototype’s maiden flight occurred on October ninth, nineteen thirty-nine but accumulated only ten hours of flight time by year-end due to engine reliability issues—insufficient for comprehensive evaluation. Consequently, in March nineteen forty its powerplants were replaced by Piaggio P.XI radial engines paired with improved nacelles and propeller spinners featuring three blades.

By May twenty-fifth nineteen forty the prototype transferred to Guidonia Montecelio for further testing—significantly behind schedule since initial plans aimed for operational deliveries by late nineteen thirty-nine. Test flights were conducted by Mario Stoppani who ferried it there and Adriano Mantelli who performed evaluations; Mantelli’s assessment was generally positive though not exceptional.

In December nineteen forty Regia Aeronautica directed modifications including adoption of twin vertical stabilizers but reversed this decision back to a single tail configuration by May nineteen forty-two while also requesting dive brakes installation along with enhanced armament and engine changes among other adjustments.

Testing continued meanwhile using P.XII engines despite their chronic issues persisting over subsequent years.

During trials without military equipment onboard to reduce weight, maximum speed reached approximately five hundred fourteen kilometers per hour (three hundred nineteen miles per hour) at about four thousand two hundred meters altitude—comparable to contemporaneous fighters such as Reggiane Re.2000 undergoing evaluation there.

Mantelli’s final judgment deemed that despite improvements over earlier models like CANT Z.1007 already in production for Regia Aeronautica—the Leone did not offer sufficient advancement to warrant replacement.

The protracted development timeline is highlighted by noting it took six months merely to complete this initial proof-of-concept aircraft amid wartime pressures—and yet construction of a fully representative prototype remained pending to validate fundamental design viability.

Ultimately nearly two years after originally planned service entry date—the aircraft’s configuration was settled.

Some experts regard this final iteration of Z.1018 as among Italy’s most aesthetically pleasing aircraft designs, noted for its sleek slender lines and refined shaping.

Experimental service

After a delay exceeding one year, an order for 100 units of the CANT Z.1018 was finally placed on 31 October 1940. Subsequently, on 26 December, a supplementary order was issued for 10 pre-series aircraft. Due to complications linked to introducing an all-metal airframe, these 10 pre-series planes were mandated to be built from wood. Like the Soviet Ilyushin Il-2 "Shturmovik," the aircraft featured a hybrid structure combining wood and metal elements. This mixed-material design presented unique challenges since integrating wood and metal—materials with vastly different characteristics—into a single airframe required careful engineering. Fortunately, Zappata’s expertise in wooden airframes, demonstrated by his successful Z.1007 model already in production with wooden construction, helped mitigate these difficulties.

Beyond the challenge of transitioning from metal to wood, ongoing government demands for modifications and enhancements further impeded production progress. Ultimately, on 5 December 1941, the first wooden pre-series unit (MM.24290) took to the skies for its maiden flight.

The two-year postponement meant that these pre-series models were entering service alongside upgraded variants of the CANT Z.1007 "Ter." Due to persistent delays and shifting priorities, by 15 January 1942 it was decided to focus production exclusively on three bombers: the CANT Z.1007, Z.1018, and Piaggio P.108. At this juncture, General Bruno mandated that the initial 100 Z.1018 units be operational by 1943.

Throughout most of 1942, the first wooden prototype underwent extensive testing, achieving a top speed of 524 km/h (326 mph) despite its heavier weight—a result primarily attributed to improved aerodynamic design. Powered by engines generating 2,013 kW (2,700 hp), it reached an altitude of 6,000 m (19,690 ft) in just over fourteen minutes when lightly loaded.

Nevertheless, flight performance was not entirely satisfactory. The aircraft demonstrated commendable ground handling as well as takeoff and landing capabilities; however, the pilot’s cockpit placement was problematic—positioned too low within the fuselage yet elevated excessively above ground level—resulting in poor visibility. In flight, stability was generally good but high-speed turbulence induced vibrations, and control responsiveness was deemed sluggish. The initial series models suffered from tail vibrations and even less responsive controls compared to the prototype. Moreover, their maximum speeds were lower than that of the prototype. Several pre-series aircraft experienced landing mishaps which, although not severe, caused further setbacks in development.

Additional trials involved several Z.1018 units. By 10 May 1943—just before the fall of Tunis to Allied forces on 13 May and near the end of the African campaign—only ten aircraft had been completed, with some still unfinished or damaged during testing phases including torpedo carriage and launch trials.

On 7 July 1943, the Italian 262 Squadron of the 107th Group within the 47th Wing received its first two pre-series aircraft for operational use; later another pre-series unit that had been damaged during landing tests was also delivered. By September 1943, only a single pre-series Z.1018 remained in active service, and none had yet participated in combat operations.

Tragically, on 8 August 1943 a pre-series Z.1018 crashed near Perugia, resulting in the death of pilot Enzo Bravi.

Meanwhile, production of the first all-metal Z.1018s proceeded. The initial metal airframe (MM.507) was completed on 22 September 1942; however, shortages of engines and other critical components hindered fulfillment of the original order for 100 units. Among the first two completed metal variants were MM.24824—a heavily armed night fighter—and MM.24826—a torpedo bomber version. MM.24824 boasted formidable armament: four 20 mm MG 151 cannons (800 rounds per gun) plus four Breda 12.7 mm/.5 in machine guns (1,400 rounds per gun) mounted in both nose and wings. This aircraft was also equipped with German FuG 202 radar technology.

Italian efforts produced indigenous radar systems such as Argo, capable of tracking naval targets, along with an airborne version called Vespa (or Arghetto), smaller yet effective for maritime target acquisition. These developments culminated in the Lepre, Italy’s most advanced wartime air interceptor radar system; however, none were installed on the Z.1018 night fighter model, which never reached full combat readiness.

Despite MM.24824’s substantial firepower—an improvement over earlier Italian fighters—the aircraft’s large size as a medium bomber meant payload capacity was ample and space constraints minimal, similar to Germany’s Dornier Do 217 which had seen limited service with Regia Aeronautica. After brief squadron evaluation, MM.24824 was seized by German forces following Italy’s armistice but was neither utilized nor survived until war’s end.

MM.24826 underwent torpedo trials alongside two other units at Gorizia’s torpedo training facility and demonstrated full capability for this role; nonetheless, none entered active service as one was lost due to ground accident damage.

Observing CRDA’s overloaded production lines handling multiple projects simultaneously, Zappata transitioned to Breda—idle after its Ba.88 program failure—to continue development work.

At Breda, Zappata proposed several metallic Z.1018 variants:

• BZ.301 (Breda-Zappata model 301), designed as a high-altitude bomber;
• BZ.302, intended as a high-altitude fighter;
• BZ.303, a multirole night fighter/torpedo bomber;
• BZ.304, an anti-tank variant possibly equipped with a 37 mm cannon.

The Italian Air Ministry approved only the BZ.301 and BZ.303 models—designated Leone II and Leone III respectively—with modified wingspans: 24 m (79 ft) for BZ.301 and 20.7 m (68 ft) for BZ.303.

The BZ.303 project featured Italy’s most heavily armed aircraft configuration: eight 20 mm MG 151 cannons (200 rounds each), split evenly between wings and nose positions plus a dorsal-mounted 12.7 mm/.5 in machine gun. It incorporated radar systems and two Piaggio P XV RC60 engines producing 1,081 kW (1,450 hp) each; an alternative version powered by DB 603 engines was designated BZ303bis. By September 1943 contracts existed for multiple units of these advanced Leoni. At this stage Germany assumed control over both CRDA and Breda factories.

German involvement began during summer 1943 when they evaluated new Italian aircraft designs including Fiat G.55s—which they favored—and others such as the Z.1018 series. Unfortunately for CRDA, German assessments judged the Leone inferior to both the aging Ju 88A-4 and even Italy’s own Z.1007ter bomber variant. This verdict severely undermined Italian bomber production plans.

Germany offered Me 410 or Ju 188 aircraft in exchange for Italian G.55 fighters—a transaction that favored German defense at Italy’s expense by trading away valuable fighters for less effective bombers from Germany’s perspective.

The ousting of Benito Mussolini on 25 July and subsequent Armistice halted these initiatives entirely as Germans assumed control over northern and central Italian industries.

Despite occupation pressures, both CRDA and Breda were permitted to continue limited production runs totaling twenty-eight units each from orders amounting to two hundred aircraft across two series.

CRDA suffered heavy destruction from Allied bombing raids resulting in only ninety-five frames entering assembly lines; twenty-eight were authorized for completion but only two were finished before German forces seized them and transferred them to Germany where their fate remains unknown.

Four additional airframes were destroyed during bombings while remaining incomplete machines were dismantled under German orders.

Breda faced similar devastation when aerial bombardments obliterated its assembly facilities on 30 April 1944; again Germans mandated scrapping all remaining equipment.

Photographic evidence captured fuselage structures revealing unpainted metallic construction—a stark contrast marking definitive termination of all Z.1018/BZ300 projects under Axis control.

Factors Behind the Leone's Lack of Success

Overall, the CANT Z.1018 Leone represented a step forward compared to the CANT Z.1007, primarily due to its twin-engine layout. However, the project was significantly hindered by ongoing modification demands from the Regia Aeronautica.

Several technical flaws also contributed to its shortcomings:

• The fuselage was too constricted to properly fit the defensive weaponry;
• Persistent vibrations in the tailplane;
• Poor positioning of the cockpit, limiting visibility during landing;
• The inclusion of a copilot added unnecessary weight since their view was restricted and control inputs were minimal;
• Frequent mechanical breakdowns;
• Difficulty in effectively incorporating the numerous changes requested by the Regia Aeronautica;
• Engines that consistently lacked reliability.

Engine issues proved to be the most persistent challenge. Various powerplants from manufacturers such as Alfa, Piaggio, and Fiat were considered for this aircraft, which ultimately never reached mass production—only about 17 units were completed in total.

The Z.1007 was often regarded as superior or at least equally satisfactory compared to its intended successor, the Z.1018, for several reasons: The Z.1007e was equipped with three engines each producing 746 kW (1,000 hp), totaling 2,237 kW (3,000 hp), which is 224 kW (300 hp) more than the Z.1018’s output. The Ter variant offered even greater power, ranging between 2,573 and 2,685 kW (3,450–3,600 hp), nearly 746 kW (1,000 hp) above that of the Z.1018. Although the Z.1007 had a lower maximum speed (490 km/h or 300 mph) due to increased drag, it could carry 50% more payload and had a higher likelihood of returning safely if an engine failed, making it the preferred model. Most importantly, its 746 kW (1,000 hp) engines demonstrated greater reliability than the 1,044 kW (1,400 hp) engines used on the Z.1018.

By 1942, the enhanced Z.1007 Ter was entering service while design adjustments and production setbacks delayed the Z.1018’s introduction. Similar to other next-generation bombers like the Ju 188, Tu-2, Do 217, Ki-49, and Ki-67—the latter being most comparable to the Z.1018—these new aircraft failed to outperform their predecessors sufficiently to justify replacement, particularly when measured against advanced versions of earlier models.

A contributing factor was the constant push for 'improvements,' which caused delays and introduced errors—a situation reminiscent of issues faced by aircraft such as the Heinkel He 177.

Additionally, Italy’s limited industrial capacity and the rapid decline of its military effort exacerbated these problems.

Consequently, although theoretically ready for production by late 1941 at best, the Z.1018 never achieved success. The availability of the Z.1007 Ter effectively terminated the program during the final year of conflict before Italy’s armistice. Even then, CRDA’s production rate remained low at about 15 aircraft monthly, while engine reliability and manufacturing speed remained inadequate.

Production Orders

The following production batches of the Z.1018 Leone were planned:

• Series I: 10 wooden Z.1018A units, MM.24290-24299, CRDA ordered on 26 December 1940
• Series II: 100 metallic Z.1018 Leone I aircraft, MM.24824-24923, CRDA ordered on 31 October 1940
• Series III: 100 metallic Z.1018 Leone I units, MM.25162-25261, Aeritalia ordered on 16 May 1942; canceled on 25 January 1943
• Series IV: 100 metallic Leone I aircraft, MM.25264-25363, Breda ordered on 8 July 1941
• Series V: 200 metallic Leone I planes; MM.26272–26471, Piaggio ordered on 29 January 1943; canceled in March 1943
• Series VI: 300 metallic Leone I units; MM.25648–25947, Breda ordered on 29 January 1943
• Series VII: 300 metallic Leone I aircraft; MM.25948-26247, CRDA ordered on 29 January 1943

In total, approximately only seventeen were constructed (ten wooden models). This limited output was the sole tangible outcome of Regia Aeronautica’’ efforts to modernize its bomber fleet during this period.

Chronology

• Early 1939: initial order placed for 32 units of the Z.1015
• 23 February: order revised to 32 units of the Z.1018
• 7 April: approval granted for the prototype demonstration model
• 9 October: maiden flight of the prototype equipped with Alfa Romeo engines
• March 1940: prototype retrofitted with P.XII engines
• 25 May to early 1941: conducted evaluations at Guidonia
• 31 October: first batch of 100 metal-framed Leone I aircraft commissioned
• 26 December: order placed for 10 Leone units featuring wooden airframes
• 5 December 1941: inaugural flight of the wooden Leone
• Throughout 1942: focus on modifications, debates, and testing of initial models; Zappata transferred to Breda to initiate BZ series design
• 22 September: first metal-bodied Leone I took flight
• By 10 May 1943: completion or near completion of ten Leone aircraft
• Summer 1943: German forces evaluated the Z.1018 and found it unsatisfactory
• 7 July: first wooden Leone delivered to an operational squadron
• July–August: production included four and three metallic Leone aircraft respectively (?)
• 9 September: armistice signed; German forces assumed control over aviation manufacturing
• 30 April 1944: bombing raids on Breda, coupled with similar destruction at CRDA, effectively terminated the Z.1018 project

Operators

Template:Country data Kingdom of Italy

• Regia Aeronautica
• Italian Co-Belligerent Air Force

Bibliography

• Garello, Giancarlo. "Il CANT Z.1018 Leone, un'occasione sprecata", Storia militare no. 12, September 1994.
• Garello, Giancarlo (September 2001). "La chasse de nuit italienne (3): la méthode scientifique" [Italian Night Fighters: The Scientific Method]. Avions: Toute l'Aéronautique et son histoire (in français) (102): 9–16. ISSN 1243-8650.
• The Illustrated Encyclopedia of Aircraft (Part Work 1982–1985). London: Orbis Publishing, 1985.
• Lembo, Daniele, "Il Cant Z.1018 Leone, il progetto più bello di Filippo Zappata", Westward editions, Aerei nella Storia no. 31, pp. 8–18.