The aircraft was of wooden construction, covered with fire birch and synthetic material. Intended powerplants were two Alfa Romeo 116 engines, an improved and turbocharged version of the 185 hp Alfa Romeo 115 six-cylinder, air-cooled, inverted in-line engine (a derivate of the de Haviland Gipsy Six). However, the improved engines did not become available in time, so the Alfa Romeo 115 was installed, accepting in advance the lesser performance.
Due to the change of engine type the aircraft was not flown until the summer of 1940 (piloted by De Michelis), however, performance was below expectations and it was unstable, during an early test flight it hit power lines and crashed. The military decided to test the BN.1 as a high-altitude reconnaissance aircraft, the aircraft was adopted for this roll while being repaired. After six months it was flown again, and till September 1941 some fifty flights were made.
It was rejected by the military, considering it too dangerous, necessary adjustments would be too costly and time consuming, hence the project was dropped, and reportedly the aircraft was scrapped in 1943. A four-seat touring version was also projected, seating two persons in tandem in each of the fuselages.
Span: 37 ft 6.8 in (11.45 m)
Length: 26 ft 8.9 in (8.15 m)
Height: 6 ft 10.6 in (2.10 m)
Wing area: 186.86 sq.ft (17.36 sq.m)
Weight empty: 3,128 lb (1,419 kg)
Loaded weight: 4,548 lb (2,063 kg)
Max speed: 224 mph (360 kmh)
Cruise speed: 180 mph (290 kmh)
Range: 684 mls (1,100 km)