Which British bomber did the USAF adopt as the B-57?

When the Canberra entered service with the Royal Air Force, its first operator, in May 1951, it became the service's first jet-powered bomber. No. 101 Squadron was the first unit to receive it. Alongside the Lightning, the Canberra was one of the two English Electric designs that became milestones of British aeronautical engineering.

In the United States it was judged that no domestically produced design could come close to what the Canberra already offered. After a competition against rivals such as the Martin XB-51, the USAF resolved to order a total of 403 Canberras. Manufacture was carried out under licence by the Glenn L. Martin Company, under the designation B-57 Canberra.

The first examples were identical to the original English Electric aircraft; later the tandem crew arrangement was introduced, and the later B-57 models were considerably modified. The company that had conceived the aircraft initially specialised in industrial electric motors and transformers, locomotives and traction equipment, diesel engines and steam turbines. The Lightning, the other design that the firm turned into a benchmark, was a British fighter that served as an interceptor from 1960 to 1988.