The raft floats off and lands wherever. It depressurizes as the altitude gets lower. Nobody gets hurt.
Skydivers, smoke jumpers and paratroopers are all taught to carry flotation gear if a water landing is even a remote possibility. I have carried flotation gear when jumping near water hazards. LPUs were the common solution. LPU 9, which i used, was a small military CO2 inflatable air bladder that cost about $20 for a pair in the early 70s. My instructor suggested always carrying a few condoms in an easily reached jumpsuit pocket. No Georger, not for that, but for use as inflatable flotation devices. If Cooper had really planned things out he would have jumped with some kind of flotation gear. I doubt if I could unwrap and inflate condoms in a night landing in the Columbia, but I sure could pull an inflation tab on an LPU. Still, it would be a struggle to get away from your gear in the dark and swim to safety. The river might win.
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