Real life, actually

One of the staff has come across a cache of Biggles books (by Captain W.E. Johns), which are sold as children’s books. But the one he’s reading, Biggles In France contains aerial warfare advice from Baron von Richthofen to the effect that: 'When attacking two-seaters, kill the gunner first'. Maybe kids in 1935, when the collection was first published, could handle that. But modern Millennial Snowflakes? It’s unlikely.