On Caustic Soda

When we were going through the manifests, the question about what exactly the caustic soda was being brought along for? So I wrote Chaz Engan, who wrote me back that: "Caustic soda is intended to absorb CO2 in the air renewal systems when flying at altitude".

So there you have it. It's also what Tyler Durden uses to mark the hand of the narrator in Fight Club, should that sort of thing somehow come in handy.