Junkers Ju 87 capacity to (500 litres in main fuel tank of which 480 litres were usable + 600 litres from drop tanks). To prevent overload conditions, bomb carrying ability was often restricted to a single bomb if the aircraft was fully loaded with fuel. The Ju 87 R-1 had a B-1 airframe with the exception of a modification in the fuselage which enabled an additional oil tank. This was installed to feed the engine due to the increase in range with the extra fuel tanks. The Ju 87 R-2 had the same airframe as the B-2, and strengthened to ensure it could
Junkers J 2 fuselage directly below the stabilizer's leading edge root. The wings had at least three different airfoil changes between root and tip, and had sections of them electrically roll-welded for stronger, more continuous bonding for greater strength. The resulting aircraft was intended to be smaller than the J 1 demonstrator, but with its steel structure, it almost equalled the J 1's completed weight. One feature pioneered in the J 2 that would also be used in later all-metal monoplanes designed and built by Junkers in World War I, was a "unitized" forward fuselage structure, combining the engine mount, wing roots and