Re: Licence required?
The current problem is that it's not the drone operators with licences you have to worry about it's the ones without.
Off the top of my head you don't need a licence for one under 7KG, and considering how prolific they are it may be too late to even try. You could go and buy one tomorrow in Maplins as could anyone else and there's no real idea of the numbers already out there.
More worryingly, assuming this report was accurate there's nothing illegal about what they were doing. We had a presentation on drones at work as part of our attempts to figure out if we need to be worried about our aircraft hitting them. The main thing that occurred to us was that we could do exactly what the drone operator in this case was doing without breaking the law. I mean I assume multiple homicides after it goes through the cockpit of a 777 might have some legal comeback, but actually putting a drone >7KG on the approach path doesn't seem to be against the law.
Would a 7KG drone damage another aircraft? Not sure, I think that's heavier than the usual bird strike tests, but then it's also a different density so the effect would presumably be different than that of a comparable weight avian. I wouldn't like to be the one to find out though.