I have a not entirely legal screener of the film (don't ask, as tsuch topics are verboten here), and just listened to this scene repeatedly, and he most certainly doesn't say "located behind the aft nacelle". I can't say for certain what he actually is saying, but it's NOT "aft nacelle". It sounds more like he's saying "located behind the arms-cell" (?), though I think it's far more likely that he's say "arsenal", though drawn out, emphasizing all 3 syllables, as "Ar-sen-al". I'd imagine that a ship's arsenal is pretty heavily reinforced, and that such an area would
be a great place to locate other essential systems, such as life support.