Leslie Frise and engine designer Fedden of the Bristol Aeroplane Co. talked the Air Ministry into accepting their idea of creating a single type out of their Blenheim and Beaufort families. The prototype flew on 17 July 1939 with the first service delivery on 27 July 1940.
The Bristol Beaufighter was a snub-nosed battleship. It was immensely strong, surprisingly manoeuvrable and a great basis for development. Armed with four 20mm cannon and four machine guns, adding rockets and torpedos, the 'Beau' served on all fronts. It was a feared opponent to the Axis powers, the Japanese calling it 'Whispering Death'.
It was sheer luck that the 'Beau' could be produced in time.
Source: Fighting Aircraft of World War II
Salamander Books