Savoia-Marchetti SM.85 - Variants

Variants

SM.85

34 production aircraft (including prototypes). There were two prototypes, 10 of the B version (with smaller engine cowling rings) built in March 1939, and 22 model Cs, fitted with a "San Giorgio" reflector gunsight and with provision for a 7.7 mm (0.303 in) or 12.7 mm (0.5 in) machine gun. They were built in July–December 1939 (MM 21689-21707 and 21847-21849). The limited production resulted in a curtailing of further type development.

SM.86

Derived from the SM.85, it first flew on 8 April 1939 fitted with 447 kW (600 hp) Walter Sagitta inline engines of Czechoslovakian manufacture. This was a totally new aircraft, only marginally similar to the previous SM.85. The specifications included: wing area 30.8 m² (331.5 ft²), length 10.9 m (36 ft), height 3.35 m (11 ft), wingspan 14 m (46 ft), weight 3,300 kg (7,275 lb) empty, and payload of 1,720 kg (3,790 lb), which was around 50% higher than the SM.85 and enough to carry all the fuel and bombs together. The performances of the SM.86 included a speed of 412 km/h (256 mph) at 4,000 m (13,120 ft), 336 km/h (209 mph) cruise speed at 5,000 m (16,400 ft), climb to 4,000 m (13,120 ft) in 14 min 17 sec.

It was remarkably similar to the Henschel Hs 129 in appearance, weight, and performance; their roles were different, the SM.86 having neither heavy armour nor cannons for ground attack (there were some similarities to the de Havilland Mosquito in that the SM.86 also utilized a small forward cockpit, inline engines, high mounted wing, and wooden construction).

The SM.86 was evaluated at Guidonia in 1939, but in April 1940, an order for 97 of them was cancelled, despite the necessity to equip a wing with dive bombers. Although the SM.86 showed an overall improvement in performance, only one was eventually built. It was used over Malta and Greece, because Savoia-Marchetti hoped to receive a contract for this new aircraft. Even though the test aircraft was downed (by a Ju 87), the aircraft project was continued despite the lack of any official interest until 1941, when it was terminated. A second prototype powered by 403 kW (540 hp) Isotta-Fraschini Gamma engines flew in August 1941. The development of the aircraft was abandoned soon after.

In any case, this new aircraft didn't compare well with the Ju 87's capabilities, even with a new set of airbrakes, flaps and other improvements (but also hampered by the addition of a new cockpit that provided poor rear and side vision for the pilot). The only marginal advantage compared to the Ju 87 was the twin-engine configuration, but the limited power of each engine was not enough to assure a return home if one of these was disabled. The air-cooled design allowed for the elimination of radiators and their vulnerability (with an improvement on aerodynamics, cost and weight), but at low speed and with a limited airflow, overheating was always an issue for this type of engine. The SM.86 was 32 km/h (20 mph) faster than the Junkers Ju-87B and even 2 km/h (1.2 mph) faster than the Ju 87D, but these differences, when compared to opposing fighter's speeds, were minimal. Without a good field of view all-around, and without the second crewmember in the cockpit armed with a defensive machine gun (nor a forward-firing weapon), the SM.86 was clearly more vulnerable to enemy fighters than the Junkers.

Although the SM.85 programme could be viewed as Savoia-Marchetti's worst mistake in wartime, this dive bomber was considered a threat by the British. They considered the possibility of suicide missions made with this aircraft against their ships, having mistaken the meaning of tuffatori.

The SM.85 was essentially made into a "training dive-bomber" as it was never really suited to being an operational machine. Its engines were not powerful enough to achieve a satisfactory performance, and even when the SM.86 was developed, with much improved engines, it was too late. One SM.85 was, however, modified into a two-seat trainer version. This was developed within a programme that lead to the advanced SM.93, another interesting and unusual aircraft, with high-speed performance and a prone pilot position. Development began too late to be put into production, as with almost all other Savoia-Marchetti "series 90s" projects. In retrospect, the SM dive bombers were a failure.