The FTL jump bent space of part of the ship’s hull (and the oxygen, beams, etc behind it) - Remember Cally spying on the Final five meeting? A lot of the infrastructure is hollow on the inside, but pressurized. Think of the jump distortion creating a pressure wave that flows through the inside of the ship, stressing the cracked beams, slamming equipment together, rupturing pipes/cables/conduits - Its actually much worse than a missle hit on armor (as armor is generally designed to either burn away or deflect the explosive impact) - the FTL jump distortion actually partially occurred IN the armor and INTO the ship.
Anyways, not sure if someone brought that up but that’s how I justified it in my mind that the jump did such horrible amounts of damage (and not just a single instance in time’s worth of damage like a missle hit, damage that seemed to take about half a minute to flow through the ship)
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