S76 Heavy
"should not the CAA have grounded the type on Tuesday and make some sort of drive train check ( I suspect that's where the cause will be found as it was a swift and catastrophic failure) mandatory before commencing flight operations?"
It would be too easy to ground any flying machine following an accident and then implement some form of inspection on "selected" components.
Would you have been happy to resume flying after an inspection of the part(s) of the drive train? What about inspecting cowlings, doors, emergency windows, main and tail rotor blades, gearbox mountings etc. etc. etc. Failure of any one of these items could ultimately cause a catastrophic crash!! (Departing cowlings and doors could impact with rotor blades etc)
Where would you draw the line without any real evidence to work on?
Nothing from the initial reports would suggest that this accident indicates a generic problem with the S76. However, some operators and clients have demonstrated prudence by temporarily suspending S76 operations.
The AAIB now has everything at Farnborough. They have no doubt been working flat out to establish initial findings and will surely make recommendations in the very near future.
Let's not jump to hasty conclusions and fire off an unnecessary panic wave.