User blog comment:IamJakuhoRaikoben/Chapter 439: Albareth Empire, Review./@comment-9595671-20150608074345/@comment-7418318-20150609080952

That's also a good point.

Any documentation about Etherion would be top secret at the highest level and thus probably only existed in Era's archives. Unless those archives were blow-ground like the prisoner cells, those documents are gone now.

So with the operating personell dead and the "handbook" for it's use gone and the construction plans as well, they might even have to start from scratch, at least for creating and learning to operate the surface based components.