212 & Crab
You've basically pointed out the two most important factors that influence 'ditching' survival before effective SAR can even be considered. That being (1) the overall probability of the pilots being able to execute a ditching at night without hitting the water hard or inverting almost immediately and (2) the detrimental effect that darkness will have on the ability of passengers to egress an inverted, submerged helicopter; all in one of the most hostile environments in the world.
If you're lucky enough at night to get out of an inverted aircraft in one piece without significant injury you then first have to prevent yourself from being washed away after you pop up from your window exit and maneuver your way into position to board the life raft. That is assuming of course, that your life rafts actually deployed and were not damaged by a hard impact or the shards of carbon composite that the rotor blades devolved into after they impacted the water at several hundred RPM. If worst comes to worse after that you may consider yourself lucky just to be alive, floating alone in the open ocean waiting for rescue that will ideally be 2-3 hours away.
Either way, this scenario and all of its dire consequences is all the more likely during the night versus the day. I do know that the pilots from Cougar who sat on the Implementation Team for the inquiry recommendations pulled no punches in describing just how difficult it would be to safely ditch the S92 at night, especially in the prevailing conditions that exist on the Grand Banks during the winter. At night, the lack of visual cues and the inability to assess sea conditions makes it very difficult to execute a successful auto rotation on the open ocean. And letís face it; this whole push by the oil companies to resume night flights is to increase the flight operations window when the days are shortest, during the winter months when the weather and sea conditions are least favorable for survival.
As for the new rig approach system that Sikorsky has developed for the S-92, I would hope that it works equally well in fog,
which we have in abundance here on the Grand Banks. From what I've read this system has the promise of increased safety margins, decreased pilot workload and reduced missed approaches during times of limited visibility, which ultimately should alleviate much of the pressure to conduct night operations because of backlog.