The Vickers-Armstrongs Valiant was a British four-jet bomber, once part of the Royal Air Force’s V bomber nuclear force in the 1950s and 1960s.
The first prototype, serial number WB210 took to the air on 18 May 1951. The pilot was Captain Joseph “Mutt” Summers, who had also been the original test pilot on the Supermarine Spitfire.

The first prototype Vickers Valiant at the Farnborough Airshow 1951, courtesy Aircraft Engine Historical Society, Inc
Sadly this first prototype was lost due to an in-flight fire in January 1952, all the crew escaping safely except for the co-pilot, who struck the tail after ejecting and received fatal injuries.
Including three prototypes, a total of 107 Valiants were built, production ending in August 1957. A Valiant B.1 (WZ366) was the first RAF aircraft to drop a British operational atomic bomb on 11 October 1956 and on 15 May 1957, a Valiant B(K).1 dropped the first British hydrogen bomb. The Valiant was retired in 1965. Follow this link for a film clip of the first prototype WB210.