For an tragic but well documented example, see https://en.m.wikipedia.org/wiki/Kursk_submarine_disaster https://en.m.wikipedia.org/wiki/Kursk_submarine_disaster

For an tragic but well documented example, see https://en.m.wikipedia.org/wiki/Kursk_submarine_disaster https://en.m.wikipedia.org/wiki/Kursk_submarine_disaster ”The submarine's emergency rescue buoy had been intentionally disabled during an earlier mission and it took more than 16 hours to locate the sunken boat, which rested on the ocean floor at a depth of 108 m (354 ft).”