In 1938, before World War II, the Italian Air Force (Regia Aeronautica) put forward new requirements for an equally new concept of heavy fighter jets to fulfill the roles of bomber escort, interceptor, fighter-bomber and reconnaissance aircraft. This high demand is met by only a few local players in the industry, including Savoia-Marchetti. Initially, the company offered SM.
88, twin-engine, twin-arm, three-person fighter jet, powered by the German Daimler-Benz DB601 series. The first flight took place in 1939, but Germany needed an engine, and the Italians decided to continue with the German Messerschmitt Bf 110 "Zwilling" for the time being.
In 1941, the Service introduced a new request for a similar twin-engine heavy fighter, this time emphasizing long-range performance and heavy firepower. Savoia-Marchetti developed SM. 91 and SM. 92 (the latter is detailed elsewhere on this page) revolves around this revised requirement, which will be based on the German Diamler-Benz DB605 family of inline engines.
The crew was reduced to two people and the armament was concentrated on no less than 6 x 20 mm MG151 automatic cannons. A heavy machine gun will be mounted on the tail to protect the key "six" of the aircraft. Range should be up to 1,000 miles, and performance will allow 395 mph.
The company's engineers again used a two-arm layout. The engine nacelles are located on the leading edge of the wing and form the front of the cantilever, and these components then extend beyond the trailing edge and are connected at the rear by a common tail. The plane is spanned by two vertical stabilizers. Crew positions (tandem seats) are concentrated behind the "pod" and short nose cone assembly in the center of the fuselage. The general design of the wing main aircraft is straight with rounded tips. "Trailing" landing gear was introduced for ground operations.
The building is all metal.
The armament became 5 x 20mm MG151 automatic cannons, which were positioned as three main guns in the nose, with the remaining pair mounted as a single at each wing root. The rear crew manages a 12.7mm Breda SAFAT machine gun on a trainable stand.
Additionally, a bomb load of 3,615 pounds can be transported.
Power is provided by 2 Daimler-Benz DB605A-1 V12 liquid-cooled supercharged in-line piston engines of 1,290 hp each, used to drive three-bladed propellers in a conventional manner.
The first flight in prototype form took place on March 11, 1943, culminating in work on two examples. Tested, SM. The 91 has a top speed of 363 mph and a range of up to 995 miles. Service is capped at 35,425 feet with a climb rate of 2,660 feet per minute.
However, as the Italians surrendered to the Allies in September 1943 and the Germans left the country to rebuild their defenses shortly thereafter, all work on the SM-91 was not completed. During the operation, the Germans claimed that both prototypes were eventually destroyed before the end of the war. Hence, SM.
The 91 could only pass its basic flight tests in the air, and its potential was never realized. In July 1944, the Germans were still testing a second prototype, but this example was lost in a heavy Allied air raid.
SM had some time in its development. The 91 was also proposed to use engines from the British Rolls-Royce "Merlin" 620 series, each with 1,300 hp, but the move was unsuccessful.
- Fighter
- Intercept
- Ground Attack
- Close Air Support (CAS)
- Reconnaissance (RECCE)
- X-Plane / Development
13.25m
64.63 ft (19.7 m)
12.63 ft (3.85 m)
6,400 kg
8,900 kg
364 mph (585 km/h; 316 knots)
35,433 ft (10,800 m; 6.71 mi)
994 miles (1,600 km; 864 nautical miles)
2,660 ft/min (811 m/min)
3 x 20mm MG151 automatic cannons on the nose.
1 x 20mm MG151 automatic cannon on port wing root.
1 x 20mm MG151 automatic cannon at the starboard wing root.
1 x 12.7mm Breda SAFAT machine gun, mounted on a trainable mount in the rear crew position.
Conventional ammunition up to 3,615 lbs.
SM. 91 - name of the basic series; two prototypes completed.