The Dutch navy aircraft had the following damage though during the ditching (in rough sea):
Lost one wing, other wing snapped off near engine, tail section and part of the rear fuselage detached. All 12 crew got out though but 3 didn't make it to the life rafts and drowned.
Source: Flight International
Re comms precautions: maybe time to consider a battery backup satellite phone in the cabin for cases where the flight deck is for some reason closed off to the crew etc. You'd need to have safeguards against sabotage of course.