improvement over the previous versions, particularly in terms of its aerodynamics. However, plans for production was delayed, in part due to technical issues that took time to resolve, and a decision by the Regia Aeronautica to place large orders for the competing CRDA CANT Z.1018 instead. Originally, 98 aircraft were ordered, but only 15 BR.20bis were built from March to July 1943, with heavy Allied bombing of Fiat's Turin factory preventing further production. There is no evidence that any of these were deployed under operation circumstances. Various experimental versions were developed. These included the BR.20C, a gunship with a 37 mm (1.46 in) cannon in the nose, while another aircraft was modified with a tricycle undercarriage. Yet another aircraft was modified to guide radio-commanded unmanned aircraft filled with explosives, but it was never used in combat. Including those bombers which had been sold to Japan, at least 233 standard BR.20s were manufactured along with an additional 264–279 BR.20Ms that were constructed from February 1940. Design Overview The Fiat BR.20 was a twin-engine low-wing cantilever monoplane medium bomber. The primary mission of the aircraft was to perform medium-range bombing runs. The BR.20 was provided with a large number of design features that were very advanced for its time: the aircraft was capable of a maximum speed in excess of 400 km/h (250 mph) and a relatively high cruise speed of 320 km/h (200 mph), being as fast as the better of its international competitors, such as the Tupolev SB light bomber. In spite of this, both the range and payload of the bomber were also comparatively favourable for the era. The engines were a pair of Fiat A.80 RC 41 radial engines, rated at 1,000 cv at 4,100 m (13,451 ft), which drove three-bladed Fiat-Hamilton metal variable-pitch propellers. A group of six self-sealing fuel tanks, housed within the center fuselage and the inner section of the wings held a combined 3,622 Ls (957 US gal) of fuel, along with a pair of oil tanks which held 112 L (30 US gal). When fully loaded with a 3,600 kg/7,900 lb payload, the bomber would have flight endurance time of 5½ hours when flown at 350 km/h (220 mph) and an altitude of 5,000 m (16,400 ft). The takeoff and landing distances were 350 m (1,150 ft) and 380 m (1,250 ft) respectively, while the theoretical ceiling was 7,600 m (24,930 ft). Armament