I read years ago that the design was stolen from Howard Hughes.
http://en.wikipedia.org/wiki/Hughes_H-1_Racer
The Germans stole the H-1 design, the Japs stole it...everybody wanted it except the U.S. Army because Hughes didn’t stop at a military base to meet with one general on his record-breaking **non-stop** transcontinental flight.
The H-1 had the range and speed to have protected U.S. B-17’s flying from Britain to bomb Germany years before the P-51 was ready. Lots of lives were lost because one general “felt” snubbed by Billionaire Hughes...