Blimps, choppers, drones, spy planes and satellites ceaselessly snap us from above these days; tourists and terrorists routinely click on Google Earth. We have come a long way since the first few silk-suited aérostiers of the French revolution ascended in tethered balloons to scan the battlefield through wobbly telescopes.
Spies in the Sky focuses on the second world war work of RAF Medmenham at Danesfield House, the mansion in the Thames Valley where pictures obtained by the flyboys of photographic reconnaissance (PR) underwent scrutiny by the scryers of photographic interpretation (PI). It was a busy place whose staff increased fifteenfold over the last four years of the war.
This book by Taylor Downing, a television producer and author of Churchill's War Lab, claims that "the photo interpreters working at Medmenham invented nothing less than a completely new science". According to Downing, their work was "more important to the outcome of the war than that of the Bletchley Park codebreakers". Most bullishly of all, we are told that "80% of all intelligence in world war II came from aerial photography". This factoid perhaps deserves a medal from the Ministry of Made-up Statistics. On page 335 of his book, Downing admits that the oft-repeated claim is in fact extrapolated from one American's statement specifically about the supply route from Burma to China.
The over-assertiveness of this book is part of its marketing strategy. Nevertheless, it is quite of a piece with the chippiness of the RAF. As the youngest of the three armed services, it seems to have suffered most from status anxiety. Downing shows the RAF as a pitiful giant that by 1939 had forgotten almost everything it had learned about photographic reconnaissance and interpretation in the first world war. Along with the Air Ministry, it was at first obtuse towards the pioneers and mavericks such as Sidney Cotton who were reinventing the skills needed, and doggedly obstructive to anyone else (such as the Royal Navy) who wanted to share its benefits. Yet Biggles pulled it off in the end: Spies in the Sky is also the story of the RAF gradually overcoming its own bureaucracy and stupidity to create a most efficient and effective part of the intelligence machine. Perhaps this book could also have risen above the spirit of the cap-badge grudge-match. Of course imagery intelligence (Imint) was important, but secret agents and spies (Humint) and signals intelligence (Sigint) also helped to win the war.
Downing writes rapidly. There are two sorts of "hero" in this racy book: the "dashing pilots" who flew "daring missions" to obtain "top-secret" PR pictures, and the "wacky boffins", "brilliant mathematicians" and "glamorous Waafs" who examined them in PI. He asserts they are "larger-than-life characters", without ever really distinguishing their specialness. It is too cursory to tell us that the ace pilot "Warby" Warburton had slightly long hair and went out with a dancer, and the interpreter Lady Charlotte Bonham Carter kept food scraps in a string bag.
Nor is this a "techie" book, designed to appeal to nerds. Downing shrinks from the nuts and bolts of photographic interpretation, which he insists on calling "a new secret science". In fact, stereoscopic photographs with a startling 3D effect were commonplace in the first world war. Geeks who love this sort of stuff will get far more from Terrence J Finnegan's exhaustively detailed and copiously illustrated Shooting the Front: Allied Photo Reconnaissance in the First World War, published earlier this year.
What Downing has done is to fit out his book like a photo reconnaissance aeroplane for a fast scoot through key wartime operations. Just as the ground crew "erks" once stripped weapons and armour to make the craft lighter, so Downing has shed detailed description of character, emotion and setting as well as scholarship, to make for a quicker read. Doping the wings with high-speed cliché helps to reduce drag. The reader is strapped into something like a De Havilland birch-and-balsawood Mosquito fast bomber, which can go at 400mph and reach 35,000ft. The point is to fly high and fast, not low and slow into critical flak.
So Wing Commander Downing zips you through the inertia of the phoney war over the famous names, Sealion, Bismarck, Tirpitz, Malta, Dieppe, the Dambusters, the horrors of Hamburg ("there was no question the bombing of German cities was justified"), the coming of the Yanks, Italy, the buildup to Overlord. There are some memorable swoops: the picture snatched by Spitfire of the German Würzburg radar set on the headland at Bruneval was indeed one of the most important photos of the war and led to the brilliant British commando raid and intelligence "pinch" early in 1942, Operation Biting. Detailed photography also assisted the precise attack by 18 Mosquitoes to help free French resistance prisoners from the Gestapo jail at Amiens in February 1944. Low-level obliques taken by pilots dicing with death in Normandy, together with 3D models created from their photographic evidence, helped to orientate the liberators landing by sea on D-day in June 1944. The best chapter in the book to my mind is entitled "Hunting the Vengeance Weapons", a vivid account of the weeks when aerial photographic intelligence truly came into its own helping to locate and destroy the V1 buzz-bombs and V2 rockets that were raining down on southern England.
Downing admits there were occasions when aerial intelligence failed – in Operation Market Garden, in the Battle of the Bulge, in detecting the Holocaust death camps – before zooming on to skim postwar developments such as the U-2, the SR71 Blackbird and modern UAVs. Lightweight and fast, Spies in the Sky makes for a breezy ride.
• Nicholas Rankin's Ian Fleming's Commandos: the story of 30 Assault Unit in WWII is published by Faber.