Flight Logistics (Heavy bombers) (Cargo Planes) (Airfields)-requires torpedo planes and monocoque construction or selective uparmouring
Steel Refinement (imperial steel armour) (advanced turrets)-requires Reticulated Plating or Shaped hulls and industrial automation
Advanced Explosives (rocket turrets) (heavy torpedoes)-requires optimal distance fuzes or saftey fuzes and active stabilisation or rapid fire rockets
Might of the Emperor (super heavy guns)-requires Steel Refinement and Imperial Science
Nuclear Theory (atomic weapons) (nuclear reactors)-requires imperial science and advanced explosives
Imperial Science (Zepplin dust tanks) (steel reinforced stone wall)-requires deep state and industrial automation





