The Eighth Passenger
An absolute must if you can find it, The Eighth Passenger (Miles Tripp). An articulate, intelligent and perfectly harrowing account of a Lancaster crew on ops in late 1944/45, told by the bomb aimer.
Also, Inside the Sky (William Langewiesche). A collection of essays on flight. Worthwhile for the chapter on bad weather flying alone.
Samurai (Saburo Saki). An extraordinary Japanese aviator who may be most respected for his skill as a fighter pilot and best remembered as one of the few ever to return - honourably - from a 'suicide' mission. Read this and being lost, low on fuel and over water will never seem daunting (or even worrisome) again. Did I mention being wounded? No? Okay, well that too.