Special 25
I fully endorse SND's post. It is important not to get carried away with sweeping generalised statements regarding night private ops. An awful lot goes on, perfectly safely and indeed it is imperative to the maximising of helicopter potential. Of course hazards are higher than daylight ops but then many forms of helicopter use have their win higher risk areas, be they North Sea, police and HEMS and these risks need to be managed and minimised. Clearly we need to wait for the accident report to see exactly why this crashed and what if any subsequent action is necessary.
Only one of your examples is relevant. As SND says, the Bournemouth 109 accident was into an airport with an ILS. The Harding accident had nothing to do with landing/taking off at night - it was a LOC in IMC in the cruise 20 miles or so from the departure point. The Carter accident probably was caused by losing visual reference on a foggy night approach.
And of course the Pete Barnes accident was daytime.
A very tragic accident though. My deepest sympathies to the families of those involved.