Wings Over the Channel follows the continuing adventures of Allan Chadwick, a young RAF pilot who completed his tour in Iraq and is now posted to the RAF aviation research center at Farnborough in southern England. It is the mid-1930s and Britain is threatened by belligerent countries such as Nazi Germany and Fascist Italy. The rapid development of high-speed bombers negates the centuries-old isolation that Britain enjoyed as an island.

Chadwick is involved in the RAF's frantic effort to build an effective radar screen and uses an early model Spitfire for liaison with outlying radar stations, flying in fair weather or foul, as he contends with the idiosyncrasies of the prototype fighter. Closer to earth he drives an old, monstrous Bentley, which attracts attention wherever he goes. He falls in love with an older, aristocratic widow who supports a secretive upper-class appeasement clique which, unbeknownst to them, has been compromised by the German Abwehr

British Intelligence decides it is impossible to keep the existence of radar a secret from the German Luftwaffe, but its effectiveness is downplayed in misleading reports fed to the Germans by Chadwick. The success of the deception-and Chadwick's life- are threatened when an accurate report of radar performance is stolen by a German spy.