A Royal Air Force vertical reconnaissance photo reveals a massive breach in a dam in May 1943.

PHOTO: IMPERIAL WAR MUSEUM—CH 9750

Aerial photography changed dramatically during World War II, but even before the war an expatriate Australian named Sydney Cotton, had—with the encouragement of the Royal Air Force—begun to explore the possibilities of marrying cameras to high-speed aircraft.

An inventor and aviation pioneer, Cotton had barnstormed in Newfound­land from 1919 to 1922 before moving on to Britain. His earliest experiments, conducted in peacetime, used modern transport aircraft like the Lockheed 12A. Camera lenses tended to frost over at high altitude and so he directed cabin air onto the cameras to solve the problem. When greater range was needed he fitted his aircraft with extra fuel tanks.

Upon the outbreak of war, Cotton applied his test results to unarmed Spitfires that would use speed and height to evade enemy defences. This meant developing newer cameras that could take clear pictures from 30,000 feet rather than the usual 8,000- to 15,000-foot altitudes hitherto flown.

Aerial reconnaissance photos are studied in 1944.

PHOTO: IMPERIAL WAR MUSEUM—HU 44269

As of Oct. 3, 1939, a special flight was formed at Heston, England. For security reasons it was initially dubbed No. 2 Camouflage Unit, but that was too obscure even for the RAF and it became the Photographic Development Unit (PDU). The first two pilots were flying officers M.V. Longbottom and Robert H. Niven, the latter a Calgarian who had enlisted directly in the RAF in 1935. Trials with Spitfires commenced on Nov. 18, 1939. Niven flew numerous adventurous sorties, none more dramatic than the one that occurred on Jan. 2, 1940. While photographing Kaiserlauten and northeast to Wiesbaden, he tried to pick up a map that had fallen to the cockpit floor. His oxygen supply became disconnected, and he blacked out at 32,000 feet. At 25,000 feet he regained consciousness, but was unable to recover from a spin until he had reached 5,000 feet. Niven was subsequently awarded a Distinguished Flying Cross for his work, but was killed May 29-30, 1942, while ferrying a Hudson aircraft to Britain.

Soon after the PDU formed two more Canadians joined it—flying officers George P. Christie of Montreal and Spencer L. Ring of Regina. They, too, were enrolled members of the RAF, having joined that force in 1937 and 1938, respectively. Ring was subsequently decorated for having flown 20 reconnaissance sorties during the pioneering period. Christie was better known for his later fighter work, but his very first aerial victory was on June 13, 1940, when, flying an unarmed Spitfire off Monaco, he forced an Italian aircraft down onto the sea and then photographed the wreck. Ring survived the war. Christie was killed in a flying accident near Montreal, July 5, 1942.

It immediately became apparent that even the sharpest photographs had to be interpreted in new ways. Smoke, cloud, camouflage, and even decoy sites complicated the process. RAF photo interpreters were trained to use stereoscopes to view pictures in three dimensions, to look for both the expected and unexpected. Scorch marks on runways would betray the first German experiments with jet aircraft, while the amount of camouflage netting in a shipyard often indicated the progress of ship construction. Constance Babington Smith, in her book Air Spy—also published under the title Evidence in Camera—wrote of the challenge when Germany began to disperse its factories either underground or to unusual sites, including chocolate factories, to avoid Allied bombing: “In 1943 the Germans had made a habit of plastering camouflage paint over their dispersal factories, which was a great help to us, because we could see at a glance which plants were being used for war production. But the (Albert) Speer regime evidently realized that when you convert buildings from other uses the most effective camouflage is no camouflage at all.”

Cotton’s PR Spitfires had been improvised; succeeding aircraft (Spitfire IV, VII, XI, XIII and XIX) were designed for the job. Every effort was made to cram as many cameras into the machines as possible. Extra fuel tanks extended the range—a Spitfire I carried 87 gallons of fuel, but a Mark XIX had 232 gallons, which could be augmented by under-wing drop tanks that could allow a further 90 to 170 gallons. Spitfires were eventually supplemented by De Havilland Mosquitos which appeared in reconnaissance versions, normally carrying four cameras for both vertical and oblique photography. The “Mossie” enabled the RAF to reach even deeper into Europe. The PDU at Heston became the Photo Reconnaissance Unit, which in turn spawned a series of squadrons dedicated to aerial reconnaissance from Europe to Burma. In Britain most of these operated under the control of Coastal Command. Inevitably, there were “turf wars”; Air Chief Marshal Sir Arthur Harris complained that an inordinate number of sorties were flown over naval targets in 1941-42 as compared to cities under Bomber Command attack.

In the absence of land operations in western Europe, most photo reconnaissance missions flown from Britain had little bearing on day-to-day operations until 1944. However, they did have strategic significance in terms of long-range planning, and as D-Day—June 6, 1944—approached they assumed greater importance in mapping the forthcoming invasion and breakout areas. No. 2 Photo Reconnaissance Unit, operating in the Middle East from 1941 onwards, was very different. It flew a variety of aircraft, including Martin Marylands and Baltimores which survived only because enemy defences were thinner in that theatre. The unit also had a tactical role to play; its reports were of almost daily use to the Royal Navy in the Mediterranean and the Eighth Army in North Africa.

An aerial photo of destroyed buildings at Essen, Germany, in 1945.

PHOTO: IMPERIAL WAR MUSEUM—CL 2377

Good cameras were crucial to effective photo reconnaissance. The F-24 cameras of 1939 through to 1941 produced prints that were too small for effective interpretation of details. The RAF rediscovered the F-8 camera, a survey instrument that dated from 1926. In January 1942 the F-52 was introduced—basically an F-24 with telephoto lens and an enlarged 500 exposure magazine (double that of the F-8). The F-52’s magnification was so great that one could discern the black crosses on an aircraft on the ground from 24,000 feet. The F-63 camera was developed for high-speed, low-level work (below 6,000 feet) where image blurring was to be avoided.

Direct Royal Canadian Air Force experience in aerial reconnaissance was chiefly of another sort. No. 110 Squadron had gone overseas in February 1940 as an Army Co-operation squadron, flying Lysanders, which had been designed for a vanished form of warfare. As of March 1941 it was redesignated No. 400 Sqdn. and in April 1941 it re-equipped with Curtis Tomahawks. These planes had unreliable engines and poor performance; training was intense but operational sorties were few. The Tomahawks were followed in July 1942 by North American Mustangs. Unlike the high-altitude PRU units, No. 400 Sqdn. operated at low level, and though equipped with cameras they were also armed with 20-mm guns.

From August 1942 to January 1944, No. 400 Sqdn. pursued two types of operations, namely Rhubarbs—low-level attacks on airfields, locomotives and targets of opportunity—and Populars—low- and medium-level photographic missions. They demanded different types of weather. Rhubarbs were flown at night or when low cloud offered protection. Populars had to be carried out in relatively clear weather. With conversion to Spitfire XIs in January 1944, the emphasis moved back to reconnaissance, but this time extending upwards to 30,000 feet.

No. 414 Sqdn., formed overseas in August 1941, initially flew Lysanders and Tomahawks before switching to Mustangs in June 1942, and then Spitfire IXs in August 1944. No. 430 Sqdn., formed in January 1943, also flew Tomahawks before converting to Mustangs and later—in November 1944—to Spitfire XIVs. Like No. 400 Sqdn., these units spent much of their early histories in offensive rather than photographic operations. Together they constituted No. 39 (Reconnaissance) Wing.

In the spring of 1944, all three units were assigned to reconnoitre the impending invasion area in general, and V-1 flying bomb launching sites in particular. After D-Day they worked in direct support of army operations.

Occasionally the tactical reconnaissance pilots were treated to a practical demonstration of their work. On July 6, 1944, Flight Lieutenant Larry Seath, flying a Spitfire of No. 400 Sqdn., took vertical shots of previously photographed bridges at Caen and Saint-André-sur-Orne. As he set course for base, Allied medium bombers attacked the bridge spans. Seath returned to record the results; the bridge at Saint-André-sur-Orne had been destroyed; those at Caen had been damaged.

If the RCAF had a reconnaissance “ace” it was Robert C.A. Waddell, who between 1940 and 1945 rose from flying officer to group captain, commanded No. 400 Sqdn. and then No. 39 Wing, flew operationally from Dieppe—in August 1942—to the Rhine crossing—in March 1945—and was decorated with the Distinguished Service Order, DFC, French Croix de Guerre and Netherlands Flying Cross. He flew his share of offensive sorties in 1942, but also numerous photo missions, even as a senior officer. These included many very low-level sorties, photographing roads and communications between the Rhine and the Elbe, prior to the Rhine crossing.

Tactical reconnaissance pilots had a photographic task to perform, but they also used “Eyeball Mark I” to gather information. They were trained to recognize what they encountered—tanks, fixed and mobile artillery, new construction, anti-aircraft sites, vehicle parks. These operations were flown at anywhere from 500 to 10,000 feet.

As already noted, the RCAF reconnaissance Mustangs flew low down and were armed. No. 414 and 430 squadron’s Spitfires were also capable of offensive as well as reconnaissance work. However, from January to May 1944, No. 400 Squadron’s high-altitude Spitfire XIs operated alongside high-flying Mosquitos. Their task was to map the forthcoming invasion area, prepare a mosaic of Caen, and report the results of tactical bombing raids on the railway and road nets leading to Normandy. This was the closest RCAF units came to practising the high-altitude tactics of the strategically oriented PRU squadrons.

Beyond the RCAF squadrons, numerous RCAF personnel were incorporated into RAF units in all theatres of war. As of January 1944 there were 11 RCAF aircrew—10 pilots, one navigator—in PR squadrons in Coastal Command alone. By June 1944, the four Coastal Command PR squadrons still had 11 RCAF aircrew, but 10 more members of the force were at RAF Station Benson, the hub of UK-based PR operations, including photo interpretation.

Even at great heights, the photographic reconnaissance aircraft were not invulnerable to interception. However, a sortie flown on March 16, 1945, by Pilot Officer Raymond M. Hays of No. 544 Sqdn. was especially remarkable. An American in the RCAF, Hays was piloting a Mosquito to the Leipzig-Dresden area when he was attacked by a rarely seen Me.163 rocket-propelled aircraft, which was soon joined by another. The Mosquito was hit several times, seriously damaging the starboard engine. The 163s had only about two minutes of “burn time” to their engines, so Hays put his aircraft through violent manoeuvres to buy time. By several accounts he came close to tearing off his own wings. He regained base, was awarded a DFC, and died in a crash on March 30, 1945.

The loss of Flying Officer Leslie Glynn Roberts of No. 544 Sqdn. on Jan. 6, 1945, demonstrated another hazard inherent in photo reconnaissance. A member of the RCAF since September 1941, he was an experienced pilot with 48 sorties when he took off on his final mission, a reconnaissance of the area east of Cologne. His time over target was estimated to be 1310 hours, but at 1532 hours, when he should have been back at base, he was heard on the radio, requesting a position “fix” and assist­ance. He crashed 16 minutes later. Investigators were unable to determine what had led to his loss, but the most probable reason was that he had stayed over his target too long, perhaps waiting for a break in clouds, and ran out of fuel on the return flight.

Matching the various tragedies were the triumphs. Arthur William Appleby of Sand Point, Ont., enlisted as ground crew in 1939. He was awarded a British Empire Medal for rescuing comrades from a crashed aircraft in Labrador. Appleby then remustered to aircrew, trained as a pilot, and went overseas in 1943. He wound up in the Far East, flying Mosquito aircraft with No. 684 Sqdn. On Oct. 30, 1944, he carried out a seven-hour, 2,000-mile sortie that included penetrating a storm front to photograph objectives down the Burmese and Malay coasts. The mission brought him a DFC.

Flying Officer John R. Myles of Saint John, N.B., had a particularly successful career, first with No. 544 Sqdn. (44 sorties) and then No. 541 Sqdn. (26 sorties). Many of his flights were made on behalf of the American Eighth Air Force which recognized his work with an Air Medal. He was later awarded a DFC following a Mosquito mission on Jan. 20, 1944, when, over southern France, the starboard engine of his aircraft failed. In spite of complete wireless and electrical failure he safely reached base. More of his adventures have been described in Volume 2 of Larry Milberry’s Canada’s Air Force published by Canav Books. Flying Officer (later Lieutenant-General) William Carr, CMM, DFC (earned with No. 683 Sqdn.) also wrote about his experiences as a PR pilot in Airforce Magazine, Autumn 2000 issue; Journal of the Canadian Aviation Historical Society, Winter 2001 issue.

Photographic reconnaissance was part of a larger intelligence-gathering system that included radio intercepts and reports from resistance groups. Its importance was emphasized by successes and failures. German warships were carefully tracked; it was a PRU Spitfire sortie that revealed in May 1941 that the German battleship Bismarck had broken out into the North Atlantic. The intelligence network gave the Allies an excellent view of German formations and defences in Normandy prior to D-Day in June 1944. On the other hand, intelligence failed in September 1944 when an unexpected movement of German forces to Arnhem—for a period of rest—thwarted the airborne assault on that river crossing. Most spectacularly, bad weather and German concealment strategy enabled the enemy to attain complete surprise when mounting their Ardennes offensive in December 1944.

High altitude photo reconnaissance had peacetime applications. Indeed, the process of “beating swords into plowshares” had begun even before VE-Day in May 1945. It would accelerate from 1947 onwards, as Australia and Canada undertook to map their respective front­ier areas while Britain launched an aerial survey of Africa.

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