Caproni Ca.135
The Caproni Ca.135 was an Italian twin-engine medium bomber designed by Cesare Pallavicino at Caproni's Bergamo subsidiary and first flown on 1 April 1936. Both fetched histories put production at 115 aircraft of all versions, scoped as 32 of the first version for Italy — eight of them later converted for Spain and the remainder re-engined — six Tipo Perù aircraft for Peru, and the Piaggio-engined Ca.135bis, which the Italian article counts as 68 aircraft for Hungary in all and the English article as 67 delivered and operated, one aircraft having been lost on its delivery flight. Italy never used the type on an operational mission; its combat career was Hungary's, on the Eastern Front in 1941–42, while Peru's six flew reconnaissance and transport work in 1941.
Why It Mattered
The Ca.135 was Caproni's answer to the Regia Aeronautica's 1934 competition for a twin-engine medium bomber, part of a modernisation plan meant to give Italy an air force of 3,000 aircraft by 1940. It was named one of the competition's winners, with 204 aircraft ordered on paper, but only a fraction of that number was ever built. The Regia Aeronautica itself never flew the type on a single operational mission, so its real career was made by its two export customers, Peru and Hungary. In Hungarian service the re-engined Ca.135bis formed almost the entire Hungarian heavy bomber force and fought on the Eastern Front in 1941 and 1942.
Design Notes
Cesare Pallavicino designed the aircraft at Caproni's Bergamo subsidiary, the Cantieri Aeronautici Bergamaschi at Ponte San Pietro, although it took its designation from the parent company's main sequence rather than the subsidiary's Ca.300 series. It was a low-wing twin of mixed construction — a welded steel-tube fuselage skinned with duralumin panels at the front and fabric at the rear, a wooden wing and wooden twin fins, with main gear legs that retracted only partly into the engine nacelles. The prototype flew on 1 April 1936, powered by Isotta Fraschini Asso XI V-12 engines that gave constant trouble through insufficient power and cooling problems. Production aircraft kept the Asso XI engines, but even in improved RC.40 form the type remained underpowered. The definitive Ca.135bis, first flown in March 1938, paired a redesigned, more aerodynamic nose with two 1,000 hp Piaggio P.XI radial engines. Its defensive armament was three machine guns — two of 12.7 mm and one of 7.7 mm — and its bomb load, in many combinations, could reach about 1,600 kg.
Operational History
Italy ordered 32 aircraft on 19 June 1937 and the type entered Regia Aeronautica service in January 1938, but its pilots criticised it heavily, and it was sent to flying schools instead of operations. Eight were refitted with Fiat A.80 engines as the Tipo Spagna for Spain; of seven ferried out in late 1938, three crashed into the sea, two turned back with icing, and only two reached Mallorca, where they sat unused. Peru had ordered six aircraft in 1936 — the Tipo Perù, with uprated Asso engines and improved turrets — and the six were handed over to a new heavy bomber squadron in September 1937. In the 1941 war with Ecuador the Peruvian aircraft stayed at their Chiclayo base and flew unescorted reconnaissance and transport sorties rather than bombing missions; one was stripped and abandoned after engine trouble forced it down in an area ground vehicles could not reach. Hungary received its Ca.135bis aircraft in two series in 1940 and 1942, after returning 33 of its 36 unsatisfactory Ca.310s, and operated 67 in all. Their baptism of fire came on 27 June 1941, the day Hungary declared war on the Soviet Union, when a Ca.135 was credited with destroying an important bridge with a two-bomb trial drop. On 11 August 1941 six Capronis attacked a bridge over the Bug river at Nikolayev; Captain Eszenyi's crew was credited with destroying the bridge, and on the way home the escorting fighters were credited with five I-16s and Szakonyi's damaged Ca.135 with three more. In 1942 the 4/1 bomber squadron, the only Hungarian bombardment unit on the Don front, fielded 17 Ca.135s, and readiness was so poor that the type's English-language history counts even 50 percent operational readiness as a great achievement.
Afterlife
In Italy, the surviving early aircraft ended their days in flying schools; the last of them were scrapped in November 1941. Hungary's worn-out survivors were withdrawn from the front line in late 1942 and relegated to training, while German-built bombers such as the Ju 88 took over their role. Peru's five remaining aircraft were taken out of service after the war, disassembled and carted away from Chiclayo; by October 1942 the last had disappeared, and their final fate is unrecorded. Caproni also flew a single heavily rebuilt derivative, the Ca.169, in 1942, but it led to no production version.