Caproni Ca.133

Caproni Ca.133

Company type	Aircraft
Industry	Aviation
Founded	December 1934 (first flight)
Founder	Rodolfo Verduzio (designer)
Products	Transport and light bomber aircraft
Parent	Caproni

The Caproni Ca.133 was a tri-motor aircraft serving dual roles as a transport and light bomber, operated by the Italian Regia Aeronautica from the period of the Second Italo-Abyssinian War through to the end of World War II.

Initially conceived as a civilian airliner and intended to succeed the Ca.101, the Ca.133 prototype made its maiden flight in December of 1934, with production commencing the following year. Military adaptations of this model functioned both as troop carriers and light bombing platforms, participating in combat across multiple theaters.

An extended version designed specifically for transport duties was introduced under the designation Caproni Ca.148.

Design

Conceived by engineer Rodolfo Verduzio, the Caproni Ca.133 represented an aerodynamic and structural advancement over its predecessor, the Ca.101. Much like the earlier model, it was engineered to be durable, cost-effective, and straightforward to maintain under challenging operational conditions. Its airframe consisted of a welded steel tube framework combined with mixed materials featuring metal and fabric coverings, alongside enhancements such as wheel spats on the main landing gear, flaps, and revised tail surfaces.

The wing assembly was positioned high on the fuselage with an approximately elliptical planform, constructed from wood and steel components. The fixed landing gear was equipped with streamlined spats. Propulsion was provided by three engines: one mounted at the nose and one beneath each wing housed within faired nacelles featuring NACA cowlings, all supported by steel tubing.

The civilian variant could carry up to sixteen passengers and was operated by Ala Littoria. The military configuration saw extensive use by the Regia Aeronautica, particularly in operations based in Italian East Africa. As a bomber, it featured two small internal bomb bays capable of accommodating up to 500 kg (1,100 lb) of ordnance, with additional larger bombs mounted externally. Defensive armament comprised four 7.7 mm (.303 in) Breda-SAFAT machine guns positioned dorsally, ventrally, and on each side. Transport versions converted from bombers—designated Ca.133T—were outfitted internally to carry eighteen fully equipped troops.

Second Italo-Abyssinian War (1935–1936)

The Ca.133 proved highly effective for colonial operations, becoming the most widely utilized Italian aircraft in such environments.

Due to their higher value and expense, the more sophisticated Savoia-Marchetti SM.81s were reserved from involvement in these 'low intensity conflicts.' Consequently, the campaign primarily relied on the Ca.101, Ca.111, and Ca.133 models.

Approximately 100 Ca.133 aircraft participated in the hostilities, performing traditional bombing and strafing missions. Additionally, they were frequently outfitted with chemical munitions such as mustard gas and Phosgene bombs—despite these being prohibited under the Geneva Protocol of 1925, a restriction Italy disregarded during this war and in Libya.

Beyond combat roles, the Ca.133 also served as a transport platform for troop support and reconnaissance duties.

With no significant aerial opposition and anti-aircraft defenses mainly limited to small-caliber weapons, air superiority played a pivotal role in Italy's ultimate conquest, culminating in the seizure of Addis Ababa in early 1936. Nevertheless, counter-insurgency (COIN) operations persisted until the onset of World War II.

Spanish Civil War (1936–1939)

Although extensively deployed in Ethiopia, the Ca.133 demonstrated inadequate performance in Spain, where it was deemed too slow and highly susceptible to attacks from enemy fighters such as the Polikarpov I-15 and I-16, as well as to intense anti-aircraft artillery fire.

World War II (1939–1945)

Within mainland Italy, the Ca.133 was predominantly employed as a light transport aircraft, providing logistical support to fighter and bomber units by ferrying supplies, personnel, and spare parts. The Regia Aeronautica soon recognized that due to technological advancements, this aircraft remained viable for combat operations in North and East Africa. At the war's commencement, 14 Squadriglie da Bombardamento in these regions were equipped with Ca.133s.

In East Africa, the aircraft continued to function in bombing and ground attack roles; on occasion, it even succeeded in downing enemy planes. For instance, on 12 June 1940 near the southern front, three Ca.133s from 66ª Squadriglia based at Yavello targeted an Allied convoy consisting of around six trucks and approximately 200 troops. Similarly, Ca.133s from 65ª Squadriglia, stationed at Neghelli, executed two separate strikes against Allied positions near Moyale, each mission involving three aircraft. That same night, ten Caproni Ca.133s bombed both the port of Aden and the Khormaksar airfield—sites previously attacked during daylight by seven SM.81s of 29° Gruppo. Additionally, three other Capronis conducted raids on Cassala airfield within the Sudan. On 23 January 1941, a Ca.133 shot down an Avro Anson piloted by Lt E.A. Gebhardt of 60 SAAF Squadron; the Anson crashed before any crew members could bail out.

The Ca.133S (Sanitary) variant was also adapted for use as an air ambulance. When hostilities began in September 1939, over 250 Ca.133s were operational, with some remaining active until the 1943 Armistice.

Postwar Service

Several units continued in civilian roles with the airline Ala Littoria. Additionally, some were sold to Austria.

The final Ca.133 was retired from the Aeronautica Militare fleet in 1947, while the last Ca.148 remained operational until 1956 under the Italian Aeroclub.

Variants

File:Caproni Ca.148.jpg

Caproni Ca.148

Ca.133

Designed for bombing and transport missions; total production reached 76 aircraft

Ca.133S

Configured for medical evacuation purposes, with 30 units built

Ca.133T

Intended for troop transport, produced in a quantity of 283

Ca.148

Extended version accommodating eight seats for civil or military use, with 54 manufactured

Military Operators

Template:AUT

• Kommando Luftstreitkräfte of the Austrian Air Force (1927–1938) operated five aircraft.
  • Fliegerregiment 1
  • Fliegerregiment 2

Template:Country data Kingdom of Italy (During wartime)

• Regia Aeronautica
• Italian Co-Belligerent Air Force

Template:Country data Italian Social Republic

• Aeronautica Nazionale Repubblicana

Template:ESP

• Spanish Air Force

Template:UK (Wartime)

• Royal Air Force
  • No. 117 Squadron RAF

Template:ITA (Postwar)

• Italian Air Force
  • Air Staff Liaison Flight

Civil Operators

Template:Flagcountry

• The airline Ala Littoria operated at least a dozen Ca.133 aircraft, primarily on routes extending to East Africa.

References

• Ca.133 reconnaissance table, Storia militare magazine n.83. (in Italian)
• Mondey, David. The Hamlyn Concise Guide to Axis Aircraft of World War II. London: Bounty Books, 2006. ISBN 0-7537-1460-4.
• Sharpe, Mike. Aircraft of world War II. Rochester (Kent) Grange Books, 2000. ISBN 1-84013-366-X.
• Sutherland, Jon & Diane Canwell: Air War East Africa 1940–41 The RAF versus the Italian Air Force. Barnsley (South Yorkshire) Pen and Sword Aviation, 2009. ISBN 978-1-84415-816-4.

External links

• Century-of-flight.net Archived 2019-07-21 at the Wayback Machine
• Caproni Ca.133 (in Italian)
• aerei-italiani.net (in Italian)
• airwar.ru (in Russian)
• Examples exported Archived 2017-04-23 at the Wayback Machine