Advanced Construction Aircraft is a unit that opens you the window to most of the T2 economy and defensive structures. In most situations when you get one, start from updating your metal extractors, geothermal powerplants and then make fusion reactors and advanced metal makers. It has a higher buildpower than its T1 version and boosts your metal and energy storage by 50. As an air constructor it has the advantage of being able to quickly access all spots on the map. Use it in packs for faster expansion in remote areas. It has a lower buildpower than land constructors.