Indie game storeFree gamesFun gamesHorror games
Game developmentAssetsComics
SalesBundles
Jobs
Tags

You can pack them tighter, right? You need a row of belt for every two rows of drill, so if the drills are wider you need less belt. 

Well, yeah. but it wont be nearly as power efficient.
And i've hardly ever ran into maps where the field is large enough to justify airblast drills.