I suspect that Dunnett was a senior civil servant who may not have been closely involved with the editing etc. of such manuals. In the inter-war years Air Publications carried the name of (I think) the Secretary of State for Air who would have issued instructions that APs were to be published, but probably didn't see even the final proofs.
Sir (Ludovic) James Dunnett was Permanent Under-Secretary at the MOD from 1966 to 1974
http://www.gulabin.com/britishcivils...20Servants.pdf