The worst of the explosions gutted the Deepwater Horizon stem to stern. Crew members were cut down by shrapnel, hurled across rooms and buried under smoking wreckage. Some were swallowed by fireballs that raced through the oil rig’s shattered interior. Dazed and battered survivors, half-naked and dripping in highly combustible gas, crawled inch by inch in pitch darkness, willing themselves to the lifeboat deck. It was no better there.