What is the name given to the final series of 7 US nuclear tests that took place in 1991 to 1992?
Operation Julin The United States's Julin nuclear test series was a group of 7 nuclear tests conducted in 1991–1992. These tests followed the "Operation Sculpin" series, and were the last before negotiations began for the Comprehensive Test Ban Treaty.
B77 nuclear bomb The B77 was a nuclear bomb designed in 1974 to match the delivery capabilities of the B-1A bomber. This included the ability to be dropped from supersonic speeds at altitudes of 60,000 feet, or in a laydown delivery at high subsonic speeds at altitudes as low as 100 feet. Meant to replace the Mk 28 and Mk 43 in the strategic role, the program was cancelled in December 1977 due to rising costs and the cancellation of the bomber it had been designed to serve. Many components of the B77 including its already tested physics package (the actual bomb core) were incorporated in the B83 which was developed in its place.