The triple tail on the DC-4E was so that the tail would be low enough to fit into contemporary hangars.
The Japanese Navy arranged for Japan Air Lines to purchase the DC-4E prototype and then gave it to Nakajima as the Navy Experimental Type D (image below from Rene Francillon,
Japanese Aircraft of the Pacific War), New York: Funk & Wagnalls, 1970, p. 423).
A good article about the DC-4E-derived Nakajima G5N
Shinzan to which YK refers is here:
Nakajima Experimental Attack-Bomber “SHINZAN” | Weapons and Warfare
I look forward to seeing your model, yankeekilo.
Karol - Are you thinking of the Breguet Br761 series? Image below by RuthAS of a Breguet Br761S No. 03 exhibited at the 1957 Paris Air Salon (
https://upload.wikimedia.org/wikiped...7_edited-2.jpg).
Don