The B46 was test fired in Operation Hardtack I in 1958 ; the fission primary ( see Teller-Ulam design ) was test fired by itself in Hardtack Butternut with 81 kiloton estimated yield , the full weapon test fired in Hardtack Yellowwood and fizzled with only 330 kiloton yield , and was fired again in Hardtack Oak to full 8.9 megaton yield
Operation Hardtack I
Operation Hardtack I
B46 nuclear bomb