Savoia-Marchetti SM.75 Marsupiale
| Company type | Aircraft model |
|---|---|
| Industry | Aviation |
| Founded | 1937 |
| Founder | Alessandro Marchetti |
| Products | Tri-motor transport aircraft |
 | This article needs additional citations for verification. (January 2008) |
Template:Infobox aircraft The Savoia-Marchetti SM.75 Marsupiale (Italian for marsupial) was an Italian tri-motor aircraft used for passenger transport and military purposes during the 1930s and 1940s. Featuring a low-wing monoplane design, it combined metal and wooden materials in its construction and included a retractable tailwheel landing gear system. It represented the final model in a series of transport planes initiated by designer Alessandro Marchetti in the early 1930s. Renowned for its speed, durability, and extended range capabilities, the SM.75 could carry as many as 24 passengers over distances up to 1,000 miles.[1]
SM.75 and SM.75bis
The SM.75 was conceived following a request from the Italian airline Ala Littoria for a contemporary airliner capable of medium to long-haul flights to succeed their existing Savoia-Marchetti S.73 models. Chief designer Alessandro Marchetti preserved much of the S.73's overall layout but incorporated retractable main landing gear to improve aerodynamic efficiency. The airframe utilized a steel-tube skeleton covered with fabric and plywood, while control surfaces were finished with plywood sheeting. Designed for a crew of four, the cabin could house up to 25 passengers. Its takeoff distance was notably short at 337 metres (1,105 feet), with an even shorter landing run of approximately 280 metres, allowing operation from smaller airfields with limited runway lengths.[2]
Propulsion came from three Alfa Romeo 126 RC.34 radial engines each producing around 559 kW. A variant known as the SM.75bis was equipped with more powerful Alfa Romeo 126 RC.18 fourteen-cylinder engines rated at approximately 641 kW.[2]
The Italian Royal Air Force (Regia Aeronautica) expressed interest in adapting the SM.75 for military use, leading to the creation of an armed version featuring smaller cabin windows and structural reinforcements to support a dorsal gun turret. This military variant also included a retractable bomb aimer’s cupola and an internal bomb bay, powered by three Alfa Romeo 128 RC.21 engines with enhanced payload capacity compared to the civilian model. It entered service under the designation Savoia-Marchetti SM.82.
SM.76
The Italian carrier LATI took delivery of its initial SM.75 aircraft in 1939. The model was subsequently redesignated as the SM.76 in 1940.
SM.87
In 1939, a floatplane variant of the SM.75 was developed and named the SM.87. This version was equipped with three 746 kW (1,000 hp) Fiat A.80 engines, enabling it to achieve a top speed of 365 km/h (227 mph), a service ceiling of 6,250 m (20,510 ft), and a range of 2,200 km (1,400 mi). It accommodated a crew of four and could transport up to 24 passengers. A total of four units were produced.
SM.90
The SM.90 represented an upgraded version of the SM.75, featuring more powerful 1,044 kW (1,400 hp) Alfa Romeo 135 R.C.32 engines and an extended fuselage compared to the original model. Only a single example was manufactured.
SM.75GA
The SM.75 GA (Grande Autonomia, meaning "Long Range") was a specialized variant of the SM.75, powered by three 641 kW (860 hp) Alfa Romeo 128 engines. It was outfitted with advanced radio equipment and additional fuel tanks to extend its operational range to 7,000 km (4,300 mi) when carrying a payload of 1,100 kg (2,400 lb). With a crew complement of four or five and a reduced load of 200 kg (440 lb), the SM.75 GA could cover up to 8,005 km (4,974 mi) at a cruising speed of 298 km/h (185 mph), operating at altitudes between 3,500 and 5,000 m (11,500 and 16,400 ft).[2]
Operational history
Italian commercial service
The SM.75 made its maiden flight in November 1937 from Novara, located in Piedmont. It entered commercial operation with Ala Littoria in 1938 and later with LATI in 1939, serving routes across Europe, extending to South America, as well as flying the Rome-Addis Ababa route established after Italy's conquest of Abyssinia (Ethiopia) following the Second Italo-Abyssinian War. The aircraft demonstrated the capability to transport four crew members along with 17 passengers and their luggage over distances up to 1,721 km (1,069 mi) at speeds around 362 km/h (225 mph) while cruising at approximately 4,000 m (13,000 ft) altitude. The SM.75 set numerous world records related to speed over distance while carrying payloads and for closed-circuit distance flights. Notably, one modified SM.75 achieved a closed-circuit endurance record of 12,936 km (8,038 mi) on August 1, 1939, surpassing the previous British record of 11,526 km (7,162 mi), which had been established by a Vickers Wellesley in late 1938.
Following Italy’s entry into World War II on June 10, 1940, civilian-operated SM.75s continued supply missions to Italian overseas possessions, although these operations diminished as the conflict advanced. Flights to South America persisted until December 1941, ceasing only when Italy declared war on the United States.
Italian military service
Upon Italy’s involvement in World War II starting June 1940, the Regia Aeronautica required reliable aircraft to sustain communication with Italian East Africa, which was encircled by British-controlled regions. Consequently, SM.75s were adapted for military use by installing a 12.7 mm (0.50 in) Breda-SAFAT machine gun mounted within a Caproni-Lanciani gun turret, necessitating an additional crew member to operate it. Furthermore, newly produced SM.75s were modified to transport up to 24 soldiers over extended distances.[2]
Special operations
Several missions of particular significance were conducted primarily to serve propaganda objectives.
Leaflet drop over Asmara
In January 1942, the commander-in-chief of the Regia Aeronautica, General Rino Corso Fougier, initiated plans for a flight from Rome to Tokyo. He sought advice from aviators experienced in extended-range flights and selected the SM.75, which offered better endurance than the SM.82 or the Savoia-Marchetti SM.83. An SM.75 was then adapted into the first long-range SM.75 GA variant.
The inaugural mission for the SM.75 GA involved distributing propaganda leaflets over Italian East Africa, which had been captured by British forces between 1940 and 1941. The leaflets bore the message: "Italian colonists, Rome is not forgetting you. We shall come back!"
On 7 May 1942 at 17:30 hours, the five-member crew departed Rome for an initial leg of approximately 2,700 km (1,700 mi). Although their intended cruising altitude was 3,000 m (9,800 ft), adverse weather conditions compelled them to ascend to 4,000 m (13,000 ft). After flying for 10 hours and 20 minutes, they reached Asmara (Eritrea) and dropped the leaflets. Instead of proceeding to Benghazi in Italian Libya as initially planned, they returned directly to Rome, completing a total flight duration of 28 hours.
Two days following their return, during a ferry flight covering about 50 km (31 mi) from Rome to Guidonia Montecelio, the SM.75 GA experienced a simultaneous failure of all three engines. The aircraft was destroyed, the pilot suffered the loss of a leg, while other crew members escaped unharmed.
Rome-Tokyo air journey
After losing the first SM.75 GA, a second aircraft was converted to the same long-range standard for the Rome-to-Tokyo mission. Completed by 9 June 1942, this aircraft was designated SM.75 GA RT (standing for "Rome-Tokyo").
The pilot leading this operation not only aimed to deliver vital propaganda for Italy but also transported updated communication codes for Japan and its Axis allies, as previous codes had been compromised by British intelligence. The extensive route included flying over hostile Soviet territory, with whom Italy was at war, making the mission exceptionally perilous.
Departing from Guidonia Montecelio on 29 June 1942, the SM.75 GA RT landed later that day at Zaporizhzhia, located in occupied Ukraine, approximately 2,030 km (1,260 mi) away—this being the nearest airfield to Japanese-controlled areas. On 30 June 1942, heavily loaded with 11,000 kg (24,000 lb)/10,340 L (2,270 imp gal; 2,730 US gal) of fuel, it executed a challenging takeoff from Zaporizhzhia’s grassy runway measuring about 700 m (2,300 ft) in length. The crew operated under strict radio silence and were instructed to destroy both aircraft and documents if forced down in enemy territory to prevent compromising Japanese interests, as Japan was not yet at war with the Soviet Union.
The flight path avoided Soviet anti-aircraft defenses and intercepted fighters—likely a Yakovlev Yak-1—while contending with severe weather conditions. The route passed north of the Aral Sea, circumvented Lake Balkhash and the Tarbagatai Mountains, then proceeded over the Gobi Desert. Due to inaccurate maps of Soviet deployments, they ascended to 5,000 m (16,000 ft) altitude to evade detection, resulting in faster oxygen depletion than anticipated. A sandstorm was encountered over Mongolia. With fuel reserves diminishing, they landed on 1 July 1942 at Pao Tow Chien in Japanese-occupied Inner Mongolia, approximately 6,000 km (3,700 mi) east of Zaporizhzhia. There, Japanese roundels were applied to the aircraft for safe passage within Japanese airspace; an interpreter boarded before continuing on the final 2,700 km (1,700 mi) leg to Tokyo.
The return flight from Tokyo commenced on 16 July 1942. Upon arrival at Pao Tow Chien, Japanese markings were removed and replaced with Italian insignia. Taking off on 18 July 1942, the aircraft retraced its inbound route and after flying for 29 hours and 25 minutes covering about 6,350 kilometres (3,950 mi), it touched down at Odessa in Ukraine before proceeding back to Guidonia Montecelio. Despite Japan’s diplomatic hesitance leading to strained relations between the two nations, Italy publicized this accomplishment; however, no subsequent attempts were made to replicate this flight.
Abyssinia Bombing Operation
In 1943, two SM.75 GA aircraft undertook the sole bombing sortie carried out by this model, targeting American bombers stationed at an airfield in Gura, Abyssinia. These SM.75 GAs were specially adapted with "Jozza" bomb sights and equipped to transport 1,200 kg (2,600 lb) of ordnance, while carrying 11,000 kg (24,000 lb) of fuel to cover the extensive distance of over 3,000 kilometres (1,900 mi) to the target. Each plane had a maximum takeoff weight of around 24,000 kg (53,000 lb). Veteran crews were chosen for the mission, which commenced on 23 May 1943 from Rhodes, then the easternmost base of the Regia Aeronautica. The SM.75 GA engines were optimized for fuel efficiency rather than maximum power, resulting in challenging takeoffs due to the heavy payload. Initially flying at low altitude, they ascended to approximately 3,000 m (9,800 ft), but after excessive fuel consumption, one aircraft diverted to bomb Port Sudan instead. The other proceeded solo and reached Gura airbase, which was discovered to be heavily fortified despite its location well behind front lines. Nearly all bombs were successfully released before returning to Rhodes the following morning, completing a flight covering 6,600 km (4,100 mi) in 24 hours and 15 minutes.
Service with Italian Co-Belligerent Air Force
Following Italy’s armistice with the Allies in September 1943, several SM.75s were incorporated into the Italian Co-Belligerent Air Force, which aligned with Allied forces for the remainder of World War II. A limited number of these aircraft survived through the conflict and remained operational until 1949.
Hungarian Use
Italy exported five SM.75 units to Hungary for operation by the Hungarian airline MALERT. After Hungary's entry into World War II, these aircraft were requisitioned for military use by the Magyar Királyi Honvéd Légierő (MKHL), known as the Hungarian Air Force.
Crash during 1941 Conflict
On 12 April 1941, amid hostilities between Hungary and Yugoslavia, four SM.75s transporting paratroopers departed from Veszprém. The lead aircraft crashed, resulting in the deaths of 23 Hungarian personnel, including 19 paratroopers—the most significant single loss suffered by Hungary during this campaign.
German Service
Post Italy’s surrender in September 1943, Germany confiscated several SM.75s which were then operated by the Luftwaffe.
Variants
- SM.75
- Civil passenger and freight aircraft; some later adapted for military use by Regia Aeronautica as cargo planes and troop carriers
- SM.75bis
- Upgraded engine version of the civilian SM.75 airliner
- SM.75 GA
- Extended-range variant of the SM.75
- SM.76
- Designation introduced in 1940 for aircraft supplied to Italy’s LATI airline
- SM.87
- Seaplane adaptation of the SM.75
- SM.90
- Version featuring new engines and an elongated fuselage
Operators
Military Users
- Luftwaffe operated captured former Regia Aeronautica aircraft.
- Royal Hungarian Air Force utilized five former MALERT civilian planes.
- Regia Aeronautica employed 32 converted civilian aircraft.
- Italian Co-Belligerent Air Force
- Italian Air Force continued operating some Savoia-Marchetti SM.75s until 1949.
Civil operators
- By June 1940, Ala Littoria was operating a fleet of 34 aircraft.
- MALERT acquired five airplanes from Italy.
Specifications (SM.75 equipped with Alfa Romeo engines)
Notes
Bibliography
- Angelucci, Enzo and Paolo Matricardi. World Aircraft: World War II, Volume I (Sampson Low Guides). Maidenhead, UK: Sampson Low, 1978. ISBN 0-562-00096-8.
- Lembo, Daniele, gli ultimi voli sull'impero, Aerei nella storia n.23, April–May 2002.
- Neulen, Hans Werner. In The Skies Of Europe: Air Forces Allied To The Luftwaffe 1939-1945. Ramsbury, Marlborough, UK: The Crowood Press, 2000. ISBN 1-86126-799-1.
- Pellegrino, Adalberto, Il raid segreto Roma-Tokyo, Storia militare n.45, June 1997.
- Rosselli, Alberto. "In the Summer of 1942, a Savoia-Marchetti Cargo Plane Made a Secret Flight to Japan." Aviation History. January 2004.
- Nakazawa, Akinori and Strippoli, Roberta, '1942-43: Italiani e Giapponesi in volo per rafforzare l'Asse Roma-Tokyo', Rivista Storica magazine Coop Giornalisti Storici, Rome, n.7/94, pp. 48-53.
Template:Savoia-Marchetti aircraft Lua error in mw.title.lua at line 359: bad argument #2 to 'title.new' (unrecognized namespace name 'Portal').