Junkers Ju 390

Junkers Ju 390 The Junkers Ju 390 was a German experimental long-range transport and reconnaissance aircraft project of Junkers during World War II. Conceived as a six-engined development of the Junkers Ju 290, it was intended to provide strategic range for missions linked to operations associated with the Battle of the Atlantic, potential flights toward North America, and support for theaters such as Eastern Front and North African Campaign. The program intersected with figures and organizations including Erhard Milch, Reichsluftfahrtministerium, and design bureaux working under the pressures of Allied strategic bombing.

Development and design

Design work for the Ju 390 followed the lineage of the Ju 90 family and the Ju 290, with input from technical staff at Junkers and oversight by the Reichsluftfahrtministerium. The conceptual evolution involved stretching the Ju 290 airframe, adding two outer engine nacelles derived from the Junkers Jumo 222 discussions and investigations into BMW 801 and Junkers Jumo 211 powerplants; the project drew on aerodynamic studies influenced by research at the Aerodynamische Versuchsanstalt and data from testing at Braunschweig. Structural arrangements included a high-aspect wing designed using techniques familiar from the Junkers Ju 52 and innovations to accommodate a large bomb bay similar to that proposed for the Focke-Wulf Fw 200 Condor and transport adaptations envisaged by planners allied with the Oberkommando der Luftwaffe. Political and strategic debates involving Hermann Göring and procurement decisions by the Wehrmacht shaped prioritization and material allocation.

Variants and prototypes

Reported variants and prototypes are a mixture of documented airframes and contested postwar claims. Primary documented configurations were the stretched fuselage six-engine prototype derived from Ju 290 prototypes tested at Werke Kassel and assembly activities at production sites tied to Dessau. Rumors and postwar testimonies reference a maritime patrol variant intended to rival the Consolidated B-24 Liberator in range, a transport configuration comparable to the Dornier Do 217 conversions, and an aerial refueling or mothership concept echoing contemporary ideas in Imperial Japanese Navy and United States Navy experimentation. Some sources cite a proposed VIP and long-range bomber adaptation that would have paralleled projects like the Heinkel He 177 heavy bomber; however, surviving German technical records in archives such as those of Bundesarchiv remain incomplete, leaving prototype counts and exact chassis serials subjects of debate among historians including analysts at institutions like the Imperial War Museum and researchers publishing in journals associated with the Royal Aeronautical Society.

Operational history

Operationally, the Ju 390 did not enter service in numbers; a small number of prototypes—if flown—served primarily in test roles at Luftwaffe test centres influenced by operational needs arising during the Battle of Britain aftermath and the intensifying Strategic bombing campaign that targeted German industry. Allegations of flights toward Bermuda and Newfoundland or a reported long-range reconnaissance sortie toward Cape Verde remain controversial and are discussed in works referencing memoirs of personnel attached to units such as Kampfgeschwader 200 and technical officers who worked with Ernst Udet-era testing procedures. Postwar interrogation summaries by personnel from the United States Army Air Forces and records held by the United Kingdom Ministry of Defence contain conflicting testimony, and investigations by scholars at Smithsonian Institution and universities such as University of Cambridge and University of Oxford have produced divergent conclusions on operational deployments.

Technical specifications

Published technical estimates for the Ju 390 draw heavily from extrapolation of Ju 290 data, wind-tunnel tests conducted at Aerodynamische Versuchsanstalt, and contemporary engineering treatises circulated within Junkers design teams. Typical reported figures include a wingspan substantially greater than the Ju 290, powerplants in a six-engine arrangement akin to the BMW 801 or Junkers Jumo 211 families, and payload capacities intended to match intercontinental ranges comparable to transatlantic designs such as the Boeing B-29 Superfortress and Consolidated B-32 Dominator. Defensive armament proposals paralleled those on Luftwaffe heavy types including remote-controlled turrets similar to experiments by Daimler-Benz and armor layouts influenced by experiences from the Eastern Front campaigns. Avionics and navigation equipment were projected to incorporate long-range radio aids and celestial navigation techniques that had been evolved through collaboration with institutions like Deutsches Institut für Navigation and navigators who served on aircraft such as the Heinkel He 111.

Surviving aircraft and remains

No complete Ju 390 airframe is known to survive in museum collections at institutions such as the Deutsches Technikmuseum Berlin, the Smithsonian National Air and Space Museum, or the Science Museum London. Remnants and parts occasionally cited in private collections or regional museums around sites like Kassel and Dessau have been subject to provenance inquiries by researchers associated with the Bundeswehr Military History Museum and independent historians. Claims of wreckage located on Atlantic islands or coastal regions tied to alleged long-range flights have been investigated by teams including representatives from the National Maritime Museum, Greenwich and archival researchers at the Bundesarchiv-Militärarchiv, but conclusive physical evidence tying recovered components to Ju 390 airframes remains absent.

Category:World War II aircraft of Germany Category:Junkers aircraft