Douglas DC-4E

DC-4E
The Douglas DC-4E in flight
Role	Experimental airliner Type of aircraft
Manufacturer	Douglas Aircraft Company
First flight	June 7, 1938[1]
Primary users	United Airlines[2] Imperial Japanese Airways
Number built	1[3]
Developed into	Douglas DC-4 Nakajima G5N

The Douglas DC-4E was an American experimental airliner that was developed before World War II. The DC-4E never entered production due to being superseded by an entirely new design, the Douglas DC-4/C-54, which proved very successful.

Many of the aircraft's innovative design features found their way into the Nakajima G5N bomber after the single DC-4E prototype was sold to a Japanese airline and clandestinely dismantled for study by Nakajima at the behest of the Imperial Japanese Navy.^[3]