Once again the dangerous myth that every ditching will be unsurvivable is trotted out. This disconcerts me somewhat; yes, it will be
much harder to pull off a reasonable impact on the sea given all the variables, but we'll all damn well give it our best shot. The last thing I want is Cabin Crew behind me who are resigned to dying because of dis-information, and the last thing any sensible passenger would want is someone who is not ready to get their (the pax, that is) rear end out of the seat and motivated towards a wet exit in double-quick time.
Anyway, for starters here's a quote from an NTSB study on my hard-drive, specifically NTSB/SS-00/01, SAFETY STUDY Emergency Evacuation of Commercial Airplanes;
In 1985, the Safety Board released two safety studies that addressed evacuation
issues. The first study examined air carrier overwater emergency equipment and
procedures. The Safety Board studied 16 survivable water contact accidents that occurred between 1959 and 1984; most of these water accidents were inadvertent, occurred without
warning, involved substantial airplane damage, rapid flooding of the cabin, and a high
chance of injury. As a result of the study, improvements were made in life preserver
design, packaging, accessibility, and ease of donning; crew postcrash survival training;
and water rescue plans for airports near water.
The 1985 study referred to is NTSB Air Carrier Overwater Emergency Equipment and Procedures, Safety Study NTSB/SS-85/02 (Washington, DC: NTSB, 1985)
You can preach doom as much as you like, but ditchings are, and have been survivable. It's not a pleasant way to spend an afternoon, is definitely not risk-free and I can think of several places I'd rather put an airliner down than the ocean or a lake but I'd do it if there was nowhere better to go, and I'd expect us all to swim away from it. You can expect to die if you so wish; that is not my job.
Interestingly, there was an article in the BALPA log about a year ago on this very issue; mentioned the fact that over rough but generally flat terrain, such as the wastes of Northern Canada, it might be better to choose a shallow lake close to shore to alight upon rather than the land itself due to the seemingly flat but actually very rough nature of the terrain. Food for thought...