Western Estimates – Historical Review

Estimated start of flight testing 1953
First discovery
Bear A 1955
Bear B July 9, 1961
Bear C February 1962
Bear D March 1965
Bear E April 1965
Bear F April 1972
Estimated start of series production 1954
First public display in practice for May Day flyby April 21, 1955
Public display of three (some observers say nine) aircraft May 1, 1955
Initial operational capability 1956
Significant operational capability 1959