When someone comes under attack for something or other, many journalists pull out the old anti-aircraft metaphor to describe it. But here, sadly, their ignorance starts to show.
“Flak” comes from a German acronym for anti aircraft fire – Fl(ieger)a(bwehr)k(anone).
A “flack” is a slightly derogatory North American term for a publicity agent.
So ditch that “c” folks – you don’t need it. Unless you are under attack by someone in PR. Then it might work…