Official text extracted from Panzer Dragoon Orta.
The military force of the Empire. With powerful mechanized airships as the backbone of their main forces, the Imperial Army is said to be the strongest military power in the entire Continent. The Army is broken up into four divisions, and is backed by a reinforcements unit, as well as a number of communications units.
Through superior military force, the Empire has secured control over half of the entire Continent within the few years after its reorganization. The huge rock-like structures around which the Imperial Warships are built are “Float Engines,” a technology recovered from the ruins of the Ancient Age.
The basic principles that cause the Float Engines to work is still a mystery, but the Imperial Academy has learned enough about their functionality that the Empire has been able to take full advantage of their power of flight. And through this great advantage is how the Empire has maintained superiority over its enemies.