Junkers Ju 252
| Industry | Aerospace, Aircraft manufacturing |
|---|---|
| Founded | 1895 |
| Founder | Hugo Junkers |
| Headquarters | Germany |
The Junkers Ju 252 was a German cargo aircraft that made its maiden flight in late October 1941. Designed to succeed the Junkers Ju 52/3m in commercial aviation, only a small number were manufactured for service with the Luftwaffe.
Design and development
The Ju 252 emerged from negotiations between Junkers and Deutsche Lufthansa in December 1938. Lufthansa was seeking a successor to the Ju 52 that offered enhanced capacity, extended range, and improved performance. Junkers responded with the EF.77 concept, which featured a pressurized cabin accommodating up to 35 passengers and was powered by three Junkers Jumo 211F engines installed in modular "power-egg" units similar to those utilized on the Junkers Ju 88. This marked a shift from the Ju 52’s BMW 132 engines, delivering a substantial performance upgrade. In comparison to the Ju 52, the Ju 252 had double the weight (13,100 kg versus 5,600), was more than 100 km/h faster (440 km/h compared to 305), and possessed significantly greater range when fully loaded (3980 km against 1300). The design process was overseen by Konrad Eicholtz.
By the time the prototype flew in October 1941, changing wartime demands redirected development toward military use with the Luftwaffe. The Ju 252 maintained its tailwheel undercarriage, which created challenges for loading due to its inclined cargo floor. To address this, Junkers incorporated its innovative Trapoklappe—a hydraulically operated rear loading ramp beneath the fuselage derived from earlier test models—that could elevate the aircraft’s tail to level the floor, facilitating straightforward cargo handling. This feature has since become a standard element in military transport aircraft design.
Although it offered significant improvements over the Ju 52/3m, production of the Ju 252 was restricted by wartime limitations on strategic materials and engine availability, as mandated by the Reich Air Ministry (RLM), which prioritized resources for combat aircraft. As a result, Junkers modified the design by increasing wooden components and substituting the Jumo engines with available BMW Bramo 323R radial engines, leading to the development of the Junkers Ju 352. Only fifteen Ju 252 units—comprising prototypes and partially completed airframes—were produced before manufacturing shifted entirely to the Ju 352.
Variants
Ju 252, original model. Fifteen constructed.
Ju 352, an adaptation of the Ju 252 utilizing non-strategic materials and powered by Bramo 323R radial engines. Fifty built.
Ju 452, a wooden-based version derived from the Ju 252.