Junkers Ju 87 of carrying a bomb, but only if not carrying the rear gunner/radio operator as, even with the Jumo 210D, the Ju 87 was still underpowered for operations with more than a bomb load. All Ju 87 As were restricted to weapons (although during the Spanish Civil War missions were conducted without the gunner). The Ju 87 A-2 was retrofitted with the Jumo 210Da fitted with a two-stage supercharger. The only further significant difference between the A-1 and A-2 was the H-PA-III controllable-pitch propeller. By mid-1938, 262 Ju 87 As had been produced, 192 from the Junkers factory in Dessau, and
Junkers marked on the J-9's landing gear wheel covers. The corrugated duralumin wing and fuselage "skin" introduced in the J-series became a trademark of Junkers aircraft built in the 1920s and '30s. Development continued during the course of World War I, including a growing (but troublesome) partnership with Fokker, as the "Junkers-Fokker Aktiengesellschaft". Several Junkers designs were licensed to Fokker during this period. The visual similarity of Junkers and Fokker aircraft during the next decade, especially after Reinhold Platz adapted some of the Junkers design concepts, but mostly crafted in wood for the Fokker designs' wing structures instead of the all-metal