The Air Force is test-dropping an upgraded, multi-function B61-12 nuclear bomb which improves accuracy, integrates various attack options into a single bomb and changes the strategic landscape with regard to nuclear weapons mission possibilities…The B61-12 adds substantial new levels of precision targeting and consolidates several different kinds of attack options into a single weapon.- Fox News Photo: Training version of a B61 nuclear bomb. An access panel on the warhead is open, showing the interface for actions such as PAL (safety/arming) and variable yield setting.