Why are these drone people so sensitive? The Oxford dictionary includes the following defintion of 'drone':
A remote-controlled pilotless aircraft
Now, whether the drone folk want to argue semantics about autonomous or semi-autonomous operation, this definition seems pretty accurate to me.
As the press are increasingly realising, for clarity of description it is preferable to use a noun (e.g. drone) rather than an acronym (e.g. UCAV) or abbreviation (e.g. RPV) - particularly if that abbreviation has a long established existing use in the same field (e.g. UAS).