AD stands for Azecreas Depository. It is a huge structure within the Azal tower which is where the majority of all materials on Terrahypt are stored. It holds ore, fuel, ammunition, textiles, etc. In addition to material storage, it also acts as a hangar for a large number of spacecraft, aircraft, and other mobile contraptions.
Sections of the building are regularly leased out for storage. And they can be deployed as individual vessels to act as a local storage in distant communities
AD also manufactures essential tools and vehicles of which are mostly centered around shipping.