Sem Model 1/72 SIAI-Marchetti S.74
Ala Littoria I-URBE
by Anatoly Isakov


Click the STORMO! Eagle to
return to the Gallery


The SM.74 was the first four-engine plane that the SIAI-Marchetti company ever manufactured. Only three aircraft were constructed, but they saw long years of service in peace and war. The SM.74 was flown by Ala Littoria first on the Rome-Marseilles-Lyons-Paris route and then on the Rorne-Brindisi line. When World War II broke out, the three planes were transferred to the military. They saw service in Africa as troop and cargo carriers, and then were used to evacuate civilians and wounded. All three were destroyed in military action. The last one was damaged during a bombing raid over the Rorne-Urbe airport on July 19, 1943.

The prototype first took to the air on November 16, 1943, and during its test flights established a world record. It flew some 620 miles (1,000 km) at 200 mph (322 km/h) with a load of ten tons. The SM.74 was a high-wing monoplane. The wing was constructed of wood, while the fuselage was built of metal with wood and fabric covering. Two of the aircraft were powered by four 700 hp Piaggio Stella X.RC engines; the third was powered by 845 hp Alfa Romeo Pegasus III engines. Lodged in NACA cowls, the engines drove two-position three-blade metal propellers. The passenger cabin was about 26 feet (8 m) long and had a bar as well as sanitary facilities. Passenger capacity varied from a maximum of 27, for distances up to 620 miles (1,000 km), to a minimum of 16, for distances up to 1,200 miles (2,000 km). Since the plane had to climb to high altitudes in order to cross the Alps, the passengers were equipped with individual oxygen masks. The SM.74's test flight performances were excellent. The aircraft could reach about 3,000 feet (1,000 m) in two minutes and forty-eight seconds; 9,000 feet (3,000 m) in eight minutes and fifty-five seconds; and 15,000 feet (5,000 m) in nineteen minutes and forty-three seconds.

The first SM. 74 was delivered to the Rome Urbe airport on March 27, 1935, and inaugurated the Rome-Marseilles-Lyons-Paris route on July 18. The other two aircraft were delivered later in the year. Beginning in the summer of 1936, the three SM.74s flew the Rorne-Brindisi line and later made flights to Libya. On the eve of the war the planes were transferred to the Reyia Aeronautica.

Soon the planes were sent to the vicinity of Benghazi, which was their base during the war. The first SM.74 to be destroyed (the second that was built) ccl1shed into a mountain on October 23, 1921. The second to go was the prototype, which was destroyed on the ground during an air raid on November 2, 1941. The last SM.74 had more than one accident, but survived until July 1943.













Construction

Dear freinds, I present an overview of my first model posted on the site - a resin model of an passenger plane the Savoia Marchetti S.74 produced by SEM Models on a scale of 1/72. The quality of the photos is only just acceptable so my apologizes. This is my first experience. The composition of the kit can be found here: Sem Model 1/72 Savoia Marchetti S.74 I-URBE ALA LITTORIA 72010

prototype is not beaten, there is not much information on it, thanks to the author of the model for consultations and interesting photos of the prototype. The model contains the main parts of the resin of two types, photo etched parts, evacuated parts, bronze casting (racks), decal on a solid substrate (need to cut out along the contour). The set itself at a cursory examination produces a favorable impression, casting defects are present in an acceptable amount, the presence of bronze stands (the model's weight is decent) and a good decal has pleased. The quality of the pilot cabin leaves much to be desired, it is very thin and does not impress the acceptable details, replacement is desirable. Etching is good, the instrument panel from Yahu Models is good, but on the assembled model is completely invisible.




Assembly:
The assembly took about 10 months with interruptions and proceeded without any special excesses for such a set, but it required a long preparation of the surface due to the local localization of the surfaces (some asymmetry of the wing profile) and the shells that opened during the processing of resin. The wing is assembled on steel pins made of thick paper clips. Applied by the manufacturer itself gluing side etched window bindings, pasted on a transparent film, showed their impracticality (they did not want to hold on, they had to glue everything to transparent resin), like the black masks prepared for them, they had to rework everything.

Of the improvements I will note:
- Replaced the lantern with a self-made vacuum, glued to a transparent epoxy five-minute resin Moment
- Hoods cast from the resin again, choosing the best specimen from the set for the prototype. The reason for the replacement is the resin from which the hoods in the kit were molded did not polymerize completely and remained rubber-like
- He put new blades out of tin, he left his sleeves
- Manufactured tailpipes made of tin solder with a flux suitable for the diameter
- I made from the photos antennas, traction, hinged flaps and other trifles
I did not photograph the stages of the assembly, because I did not plan to upload them initially.

Paint:
GS Primer Surfacer, acrylic paints Tamiya and GS Hobby Color. Colors prevented himself. Glossy acrylic lacquer Tamiya X-22 under the decal and after its application in several layers, to eliminate the step from the decal. Intermediate grinding. Oil points and washings - paints "Sonnet" on pinene (terpentin). Finish varnish - glossy varnish Vallejo.

Conclusion:
The model requires experience when working with resin and etching, in addition, because of the large size (with B-17), a slight deformation of some large parts of the set is inevitable when casting into a rubber mold. A number of small parts are easier to make anew than trying to apply native. If there is a desire to put in the collection a model of this rare plane, there is practically no alternative at the moment (the vacuum from Broplan does not count).





SM.74 MM.21001 formerly I-URBE was operated by 604a Sq and used extensivley in Libya until it was destroyed on the ground at Castel Benito, Libya, 2 Nov. 1941.

Technical Specifications

Aircraft: SIAI-Marchetti SM.74
Manufacturer: SIAI-Marchetti
Type: Civil Transport
Year: 1935
Engine: Four Piaggio Stella X.RC. 9-cylinder radial, air-cooled, 700 hp each
Wingspan: 97 ft 4 in (29.68 m)
Length: 70 ft 1 in (21.36 m)
Height: 18ft 1 in (5.50m)
Weight: 30,8001b (14,000kg)
Cruising speed:186 mph (300km/h)
Ceiling: 23,000 ft (7,000 m)
Range: 620 mile (1,000 km)
Crew: 4
Passengers: 27

Additional Images

STORMO! Products









June, 2018
STORMO! 2018