Hitlerjugend: An In-Depth History: 1937 - Jahr der "Heimbeschaffung" - Year of the home
by Arvo L. Vercamer

Hitler and the HJ leadership were well aware of the fact that up until now, there were few specialized activities outside of the Allgemeine HJ, which might attract still more German youths. To alleviate this, the HJ-Flieger (aviation) and HJ-Marine (marine) and HJ-Motor (cars and engines) groups were established. Each of these groups would specialize activities and functions around its theme name.