German Junkers Ju 390
About mid-way through the war, Luftwaffe high command realized the one error they had made in pre-war planning was that the air service had not developed a long-range heavy bomber that could strike the United States. This realization came as British and American heavy bombers were striking German cities.
So engineers got to work on developing a long-range heavy bomber and the Junkers Ju-390 was the result. Powered by six BMW 801 engines, the plane had a wingspan of 165 feet and a top speed of 314 miles per hour, with a range of more than 6,000 miles. The plane was part of the “Amerika Bomber” project and was being developed along with the Messerschmitt Me 264, the Focke-Wulf Ta 400 and the Heinkel He 277.
Test flights for the Ju-390 got underway in 1944 and the plane was found to be powerful and effective, but by then Germany was on the defensive and fighting for its survival, so offensive bomber projects were given low priority. Junkers could only produce two prototypes before the war’s end.
Some reports said that the Luftwaffe flew one of the prototypes into U.S. airspace before turning around.