This excellent read describes the night a sailor was presumed dead after falling overboard a 27ft yacht and lost at sea for five-and-a-half hours in a holed lifejacket, at night in the Bay of Biscay.
One of the many lessons learned, he says, is to “Wear a personal locator beacon (PLB) on your lifejacket – improvements to technology have been made based on people like me who come back after falling overboard”
Read more here:
https://www.pbo.co.uk/seamanship/left-for-dead-after-falling-overboard-how-one-sailor-survived-5-hours-lost-at-sea-before-rescue-95024