Russia's Rosatom has made an RITM-200 reactor that is powered with nuclear energy. They are making icebreaker ships powered with a nuclear reactor inside of the ships; making an almost power plant on the water.
Dive-bomber/ground attack fighter were a key factor during World War 2, for they are small enough to bomb a key area without harming the area around it (like a enemy HQ within a town), but, they are big...
Helicopters comes into mass production for military use when World War 2 have ended. As the 2 world superpowers, namely USA and USSR, were at a rush of improving and upgrading their armed forces in case...