Many years ago when we still had an Air Force worth talking about we were returning to base across the North Sea, routing from Manston to coast in in the Netherlands. Having foolishly been suckered in by the Met man’s reasonable forecast, we found ourselves being forced down lower and lower by freezing cloud and snow, in which our helicopter was prohibited from flying. About two thirds of the way across we were at less than 100’ in very poor visibility when a very large ship loomed out of the mist very close ahead. It was much taller than our transit height. We missed it but not by much. I reckon he should have given way but we broke hard right to avoid anyway. We learned about flying AND shipping from that.