apologies if people have already written about this - is there a ditching course that one can attend in the UK that anybody knows of?
I did a maritime survival course. The same stuff they run on weekdays for oil rig crews was run by volunteers from a diving school on Saturdays. Same theory, same pool, same everything. Except we wore our dive suits instead of drysuits.
It included dunker training in a mock helicopter. The feeling of desorientation is very sobering.
Unfortunately it's in Dutch only:
Indoor | Get Wet Maritiem
You might be lucky and find the same concept in the UK. Otherwise you'll need to look for the professional courses, but they won't be cheap.