"Gun Button To Fire" by Tom Neil.
Staggeringly good. His description of shooting down a Messerschmidt (his first confirmed kill) is remarkable.
Ernest Gann's "Island in the Sky" is breathtaking. A novel that grew out of his story (In "Fate is the Hunter") of the C54 lost over Canada which put down on a frozen lake. The aeroplane's flight into impending danger, carburetors icing up, fuel running low, no idea where they are.The airframe icing up and the way he describes the Captain's thought processes and the conclusion he draws as he runs out of options must surely represent some of the finest aviation prose you will ever read. I defy anyone to read that chapter without experiencing the cold chill of icy fear running down your spine as you turn each page. Unbelievable.
In fact anything Gann wrote is worth a read. "Twilight for the Gods" about an obsolete sailing vessel on its last voyage. Magnificent.