You get this card as soon as you want it (which should be immediately), it provides you with resources and gives Aerial to boot. I know Champions has been overly cautious about cards that require the Aerial trait, but they seem to be coming out of the woods a little with these two latest hero packs. (Ironheart and Nova)
Nova also readies this helmet every time he takes a basic action, so you're going to get two uses most rounds. Add in the Connection to the Worldmind and Nova is not hurting for resources.