The Aircraft
The Junkers Ju-52/3m was a continuation of the Ju-52/1m. The 3m stands for three engines (dreimotoren), the 1m stands for one engine (einmotor). The prototype was built with one engine, but it proved to be badly underpowered, so two more engines, one on each wing, were added.
The other feature of the Ju-52 was the corrugated skin on the wings and fuselage. The idea, originated by Junkers in World War I, was to add strength to the aircraft without adding weight. The Ford Trimotor used this, too. Although it worked, the corrugations added drag. It can also be an additional task for the modeler when filling seams.
The Kit
The PE set consists of two frets of PE. They seemed to be set up so that one covers the interior, the other the exterior. Some of the parts are prepainted, and some are left in “natural” brass.