Wave height and MOB at night

If you have any doubts about how wave action affects your chances of seeing a flashing light, try a practice man-overboard pick-up on a rough night using your floating emergency ‘flasher’ to mark the dummy. It’s a salutary experience, especially with the expensive millisecond super-powerful strobes which often seem to light up just after they’ve ‘disappeared’ time after time. It makes a lot of sense also to equip a solitary watch on deck with a small waterproof torch for the oilskin pocket. At least that will be showing a glim every time the victim reaches the top of a wave.