I work as an ATCO in the LTMA. We get reports of drones every week from professional pilots.
Nige321 (post 18) and rightstuffer (post 38).
You doubt the size of the UAV's encountered near major airports, or that they can reach a decent altitude...
3 separate pilots reported a lit drone, over a metre wide, at 17000' in the vicinity of Big just recently... There have been many more reported at several thousand feet.
Unlike Tourest who is blase about this; they do present a real risk. You can't have an attitude of 'the engine will be damaged but shut down safely'... we are talking about flights at a critical stage... there is a risk; it needs to be dealt with.