Quote:

Well, it does make a distinction from a bumblebee.



Or the unchanging notes of, say, a bagpipe.

Seriously, folks, it is generally obvious from the context, and, in this case there's no chance that someone tuned in halfway through the story, but it still serves to distinguish the pilotless airplanes from male bees or lazy men or people engaged in mind-numbing work. It might be redundant but hardly worth someone going all Iowa over.