Upon its introduction, the BR.20 was a cutting-edge aircraft and benefited from an overall good design, however, the bomber quickly became obsolete in the face of rapid advances made in the field during this era. The scarcity of improved versions of the aircraft condemned the BR.20 to be only viable in the role of a second-line machine, being underpowered and lacking in defensive firepower by the outbreak of the Second World War. By the time Italy had entered the Second World War, a new variant of the bomber, designated as the "BR.20M", had been produced and put in service. The improved BR.20M featured a different nose provisioned with additional glazed sections for the bombardier, along with a slightly longer fuselage. Also, the weight was increased because a part of the fabric was substituted with metal, improving the resistance to flutter and vibration from the engines while reducing speed from 430 km/h (270 mph) to 410 km/h (260 mph).