SIAI S.50

Vickers-Terni

Industry	Aerospace
Headquarters	La Spezia , Italy
Products	Aircraft manufacturing (including Marchetti MVT / SIAI S.50)

The Marchetti MVT, which was subsequently designated as the SIAI S.50, was an Italian fighter aircraft developed during 1919 and the early 1920s.

Design and development

The MVT, standing for "Marchetti-Vickers-Terni," was conceived by Alessandro Marchetti (1884–1966) as a single-seat, all-metal biplane featuring a fuselage positioned between its upper and lower wings. The rear section of the fuselage was flattened deliberately to function as an airfoil. Its semi-elliptical wings were notably thin in profile and utilized wing warping for lateral maneuvering, complemented by fully movable tail surfaces. The aircraft was equipped with an SPA 6a water-cooled engine delivering 164 kilowatts (220 horsepower) to a two-bladed propeller, and it carried two fixed, synchronized 7.7 millimeter (0.303-inch) Vickers machine guns firing forward through the propeller arc.

Manufactured by Vickers-Terni at their La Spezia facility, the MVT took to the skies for the first time in 1919. On December 9 of that year, it achieved a top speed of 250 kilometers per hour (155 miles per hour), setting an unofficial world speed record; however, this record lacked official recognition due to the absence of observers from the Fédération Aéronautique Internationale, the authoritative body overseeing aeronautics worldwide.

In 1920, Marchetti undertook a redesign of the MVT which incorporated longer-span wings with outward-angled interplane struts, a newly designed Cabane strut, and an upgraded SPA 62a engine rated at 234 kilowatts (285 horsepower). Testing of this revised version at Guidonia Montecelio resulted in a maximum speed of 275 kilometers per hour (171 miles per hour).

When Marchetti became chief designer at the SIAI company in 1922, the MVT was rebranded as the SIAI S.50. Although it did not fulfill the Regia Aeronautica's 1923 single-seat fighter competition criteria—which mandated the use of the 224-kilowatt (300-horsepower) Hispano-Suiza HS 42 eight-cylinder water-cooled engine—SIAI nonetheless submitted it for consideration. The aircraft received a sufficiently positive evaluation that led to the Regia Aeronautica acquiring three units for further assessment and contemplating an order for twelve additional planes; however, these twelve were ultimately neither ordered nor produced.

Insights gained from operating the S.50 during the 1923 contest inspired Alessandro Marchetti to develop a successor model known as the SIAI S.52 fighter.

Variants

Among the three S.50 aircraft operated by the Regia Aeronautica, one was adapted to serve as a twin-float floatplane version.

Operators

Template:Country data Kingdom of Italy

• Corpo Aeronautico Militare
• Regia Aeronautica

Specifications (MVT with SPA 6a engine)

Source: Template:Aircraft specs Additional performance data:

• Climb to 1,000 m (3,281 ft): 2 minutes
• Climb to 5,000 m (16,405 ft): 11 minutes

References

• Green, William, and Gordon Swanborough. The Complete Book of Fighters: An Illustrated Encyclopedia of Every Fighter Aircraft Built and Flown. New York: SMITHMARK Publishers, 1994. ISBN 0-8317-3939-8.