Junkers Ju 87 would be carried out by the Weserflug company after April 1938, but Junkers continued producing Ju 87 up until March 1940. A long range version of the Ju 87B was also built, known as the Ju 87R, the letter being an abbreviation for "Reichweite", "(operational) range". They were primarily intended for anti-shipping missions. The Ju 87R had a B-series airframe with an additional oil tank and fuel lines to the outer wing stations to permit the use of two standardised capacity under-wing drop tanks, used by a wide variety of Luftwaffe aircraft through most of the war. This increased fuel
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