Very nice work!
A friend of mine said that the B-18 was a very nice peacetime aircraft, that even featured a supply of corks that you could insert as required to keep the water from coming into the fuselage after a ditching, thereby easing recovery of the aircraft.
Here's another stepsister of the DC-2, which proved to be much more attractive as well as much more successful. Those Japanese girls are always so much slimmer! From the Profile Publication.
It wasn't. This sounds like one of those times in the 1930s when the US couldn't believe the Japanese could build anything modern without stealing it. Although looking in Japanese Aircraft 1910 - 1941, in the G1M1 or Ka-9 as the company called it, the designers were influenced in their application of modern manufacturing techniques by products of the Junkers concern that had made it to Japan, notably the K 37. Apart from one of the engineers responsible for the design, not one of the Mitsubishi team had any experience in building a modern all-metal design. Not bad for a first time.