The account I heard about a Sikorsky S-58T Ditching was a bit amusing.
You hit the switch to arm the floats and Salt Water Immersion switches did the dirty work for you. The interesting bit is it takes a bit of time for the Saltwater and Switches to shake hands and then it takes a bit of time for the Floats to inflate.
My Chum said all went well following a decent arrival into the water....he heard something akin to the Alka Selzter sounds....Pop Pop....Fizz Fizz....and as the water began to go up over the wind screen he took a very...very deep breath thinking he was going to need as much as he could hold.....when out of the deep up she rises....wallowed back and forth and soon settled down very nicely all cozy and dry.