Posted by: darthziggy16
As far as I know, the achievement is only concerned about the levels where you play as the Rookie, which is why it says, "no engineers in the city at night." I know the level you're referring to is technically at night, but since all of the Rookie's levels take place in the dark, it's just talking about those. Plus, it's pretty much impossible to beat the flying level without taking out those last few pods (the ones that cause the major explosion around the Phantom).
Good luck!
yeah this is correct, and im fairly sure the achievement unlocks before this mission but i might be wrong. also, to get the achievement the easy way. chuck it on easy and run through the entire game without firing a shot :)