Staff Writer (Updated: 8/29/2015):
Interestingly, the Junkers Ju 390 heavy bomber came along during the war when the German effort and philosophy was still generally concentrated on use of medium bombers and various fighter-bomber hybrids. As such, full developmental resources for the Ju 390 were never really realized and the entire program floundered as a result. With origins in the Ju 290 airframe, the Ju 390 was essentially the same aircraft with wings lengthened via extensions to help accommodate additional engines (three engines were fitted to a wing for a total of six). The fuselage was also lengthened for the long-range bombing role. Defense was supplied by a pair of 13mm machine guns in a ventral gondola position as well as 2 x 13mm machine guns at beam (waist) positions. A pair of 20mm cannons would have been mounted in a dorsal turret and a single 20mm cannon would have been installed in the tail. The operating crew complement was to number ten between the required flight crew and dedicated gunners. The heavy transport form was given the designation of Ju 390A-1 while the maritime patrol and long-range heavy bombers were known under the Ju 390B and Ju 390C designations respectively.
Power for the Ju 390V1 prototype was through 6 x BMW 801D radial piston engines delivering 1,700 horsepower each. This provided for a maximum speed of 315 miles per hour and an operational range of 6,030 miles. The aircraft's service ceiling reached just 19,700 feet. Empty weight was listed at 87,100 lb while Maximum Take-Off Weight reached 166,400 lb. Structurally, the Ju 390 featured a length of 112 feet, a wingspan of 165 feet, and a height of 22.6 feet.