The American army flying corps started development in ancient times in 1941 under World War II. However, to Europe, directly, with the technology of those days in which a bombing flight is possible, since the demanded performance was difficult, it brought a result of completion from the U.S. mainland after the great war. However, it is the bomber with which there is also the beginning of a cold war time and no less than 333 sets were produced as real time for opening hostilities as a result. It left the name to history as a giant machine which also has a name of a peacemaker and has six sets of promotion formula reciprocating engines, and an auxiliary jet engine.