So, you didnt see anything, no evidence left behind, so it must be a drone? Ok. I doubt it. How about a crack in the screen not picked up on the pre-flight? How about a bird? Just because there is no evidence it must be a drone? Really?
Registration of all drones? What a joke. Who is going to manage that database? Who has the manpower? in the UK the CAA don't have enough manpower to manage the commercial legal activity within a sensible time frame right now. Never mind the registration of millions more UAV's.
What about those people who build their own? No serial numbers.
I suppose people have to blame something and drones seem to be flavour of the month right now ( every month)