Duel of Eagles attempts to straddle a grand history of the Battle of Britain with individual pilot accounts, and doesn't quite manage to do justice to either of them. While a solid history, it's likely been supplanted by more recent works.

The story starts back in the First World War, with the initial Zeppelin bombing raids on England and the organization of the Royal Air Force, and then ambles through the 1920s and 30s as various pilots come of age and become obsessed with flying, everybody cuts defense budgets, Hitler rises to power, and Germany embarks on a genocidal war of conquest. The Fall of France happens about half of the way through, to give you an idea of the pacing.

The grand history is one of RAF commander Dowding against Goering's Luffwaffe. Britain had a just barely sufficient defensive system, with a small margin of modern fighters, but more importantly a chain of radars and observes integrated into central command posts such that Hurricane and Spitfire squadrons could be vectored on to incoming bombers. Dowding had internal enemies to match the Nazis; political superiors who had underinvested in defense for years, and insubordinate commanders who favored a "Big Wing" tactic of massed defense too slow to repel bombers. But the main enemy was Goering, who along with numerous personal weaknesses, addiction, emotional volatility, not being very smart, being a Nazi, etc., had to contend with an airforce operating at the end of its range, and constantly shifting strategic objectives. Townsend argues that attacks on airfields and radar very much had fighter command on the ropes, when an RAF bombing of Berlin caused retaliatory bombing of London and other "strategic" targets to prepare for the invasion of England. If the Luftwaffe had fought an air superiority campaign, they might have won!

This story is all very interesting, but handled better in Korda's With Wings Like Eagles (a much younger Korda is acknowledged by Townsend for help with the research). Where Townsend has unique insight is that he was an RAF fighter pilot who fought in the Battle of Britain, and could tell the stories of his comrades and the enemy pilots as their peer. The personal narratives are fascinating, but there's not enough for a thorough oral history, and while Townsend is a serviceable writer, he's not quite up to the grandeur of flight and sudden death in the air.

While somewhat obsolete, this book is a still worth a look for the airpower buff.