If I may settle the matter of which book. As it happens I havent read Max Hastings' book, excellent as I am sure it is, but I have probably read Bomber at least half a dozen times and can assure you Len Deighton makes reference to resentment towards sergeant aircrew from older SNCOs. As P-N has said, Deighton researched the book very thoroughly, so I have no doubt he got the story from a similar source to that used by Hastings.