As the 21st century was coming to an end, the humble Physics rose to popularity once again due to the major breakthroughs stemming from the Supercondutor and, consequentially, the United Field Theory. Among other rewards, this knowledge allowed engineers to design new ways of excerting force, which led to experimental vehicles with gravimagnetic propulsion. This type of engine soon revolutionized transport, as it was not only very efficient, but also silent and harmless to the environment, since it could run on almost anything solid or liquid. The Hannabu, as it was called after mythical machines thought to be researched by the Germans in the early 20th century, became a general term for any military aircraft employing the GM drive, but especially for small assault and transport units. Sceptical at first, military officers quickly learned to love these machines for their reliability, self-sustenance, and overall performance. Hannabus of various sizes and types remained in military use for two centuries, outliving many later, more advanced designs.