Given the apparent susceptibility of the AS350/5's cabin to 'falling off' at the slightest provocation (okay, well
some provocation) and given that they are still being produced .. wouldn't it be possible for our friends in Marignane to install a couple of roof spars extending say from the engine deck (where perhaps the spar could be mounted) forward into the fabric (or underside) of the cabin roof and in the general vicinity depicted by the yellow stripe in the image below?
Proposed cabin strengthening (both sides) within the vicinity depicted by the yellow stripe