Home   Genealogy   Forums   Search   Contact
MHO Home
MHO Home
 17th Century
 18th Century
 19th Century
 American Civil War
 World War I
 World War II
 20th - 21st Century

 Write for MHO
 Search MHO
 Civil War Genealogy Database
 Privacy Policy

WWII Articles
USS North Carolina vs Bismarck
Operation Compass
Book Review: APc-48
Agent 110: An American Spymaster
Rudolf Hess/Tancred Borenius
Soviet Rifle Corps of WWII
The Morality of Okinawa
The First Class at RAF No. 31 Radio School
Operation Dragoon and Invasion of Southern France
Battle of Buna-Gona
The Silent Service and the Turkey Shoot
Published works on WWII OOB for land forces
Flying Tiger, Hidden Eagle
SAARF – Special Allied Airborne Recon Force
Force at la Difensa
Sabotaging Hitler’s Heavy Water
Soviet Offensive in the Arctic
The Failure of Strategic Bombing
Dutch Harbor: Unraveling of Japan’s Pacific Strategy
Ed Ramsey, 26th Cav Reg (Philippine Scouts)
US Army in Czechoslovakia '45: An Operational Overview
Strategic Culture of the IJN
Battles of Luneville: September 1944
Visual Guide to US Fleet Subs Pt 1
Lodge Act Soldier
The Fate of the Kido Butai
Air Recon in WWII
Turning East: Hitler's only option
Resupply Operations to Malta, 1942
WWII Veteran Interview
Why Arnhem?
Hell Ship - From the Philippines to Japan
The Battleship USS Oregon
US Army in Czechoslovakia '45 to '48
Jewish Resistance in WWII
Battle for Seaports
Banzai Attack on Attu
End of the Battle of the Java Sea
Texas National Guard in WWII
How Arnhem was Lost
Saga of Ormoc Bay
Silent Service of the Pacific
USS Wahoo
Polish Cavalry: A Military Myth Dispelled
Confucian Martial Culture
Operation Market Garden
Legacy of WWII Sub Veterans
Lausdell Crossroads
Kasserine Pass
Arnhem Startline
Bushido: Valor of Deceit
British Offensive Operations
Sir Winston Churchill
American Stubbornness at Rimling
The OSS in Greece
Strategy of Blitzkrieg
Breaking Seelow Heights
The Rape of Nanking
Small Battle: Big Implications
Harris Class APA's
Aerial Defense of East Indies
Why the Bulge Didn't Break
American Forces in WWII
Shadow Warriors
Battle of Surigao Strait
Panzer Brigades
Adolf Eichmann
Interview of a WWII Veteran
Failure and Destruction
Winter Warfare
Operation Rusty: The Gehlen-U.S. Army Connection
Was Hitler right to invade Russia?
Hitler, Germany's Worst General
Surface Actions of World War II
MacArthur's Failures in the Philippines
Japan's Monster Sub
Popski's Private Army
The Soviet Formula for Success
Japan's TA Operation
Hitler Youth: An Effective Organization
After Midway: The Fates of the Warships
Barbarossa: Strategic Miscalculation
The Story of a "Go Devil"
Long Range Desert Group
Island of Death
The Failure of Operation Barbarossa
The Liberation of Czechoslovakia 1945
Only the Admirals were Happy
Bicycle Blitzkrieg - Singapore
Good Grief Sir, We're in Trier!
Thermopylae, Balaklava and Kokoda
How Hitler Could Have Won
The Battle of Midway
Waffen SS - Birth of the Elite
Nomonhan and Okinawa
Der Bund Deutscher Mädel
Rulers of the World: Hitler Youth
Breakout From the Hedgerows
Memories of D-Day
Motivation of the Einsatzgruppen
Pearl Harbor and Midway
Amphibious Assaults during WWII
The 9th SS Panzer Division
The Warsaw Uprising
Sea Lion vs. Overlord
Maginot Line
Battle of Bastogne
Battle of the Barents Sea
Anzio: The Allies' Greatest Blunder
US Army in WWII
Battle of Mers-el-Kebir
Hitler's Ultra-Secret Adlerhorst
The Wilhelm Gustloff Disaster
The 88th Infantry in Italy

Del Kostka Articles
The Somme
Mapping the Western Front in WWI
Dutch Harbor
Air Recon in WWII
Air Recon in WWI
Banzai Attack on Attu

Recommended Reading

The Eight Ballers: Eyes of the Fifth Air Force: The 8th Photo Reconnaissance Squadron in World War II

Combat Recon: 5th Air Force Images from the Sw Pacific 1943-45

Ads by Google

Air Reconnaissance in the Second World War
Air Reconnaissance in the Second World War
by Del C. Kostka

In 1919, the great arsenals of the world lay in ruins. After four years of bitter conflict, weary governments eagerly scrapped the instruments of war that spread so much carnage and destruction across the continent of Europe. A global peace movement and tight fiscal budgets conspired to keep military development to a minimum during the post-war era, and in almost every nation’s air service the discipline that suffered the most was aerial reconnaissance.[1] It would be a shortsighted policy. Just twenty years after “the war to end all wars," an even greater global crisis would once again prove the indispensable nature of strategic aerial reconnaissance in modern, mechanized warfare.

Legacy of the Great War

Without question, air reconnaissance had an enormous impact on military operations during the First World War. Airborne observers provided clarity and situational awareness for battlefield commanders (Tactical Intelligence), and air photo interpreters provided information about the enemy’s strength, logistics and capabilities (Strategic Intelligence). But the intelligence value of air reconnaissance in the First World War was considered secondary to the role that aviation played in guiding artillery fire. Airborne artillery spotting, when combined with new wireless communication and artillery technologies, constituted the most lethal weapon system of the war. In fact, airborne artillery spotting was so effective that most post-war military strategists considered air reconnaissance simply an extension of ground operations.[2]

The Inter-War Years

One strategist who did not discount the broader strategic potential of air reconnaissance was Capt George W. Goddard, Chief of the US Army Air Corp Photographic Research Division. During the 1930’s, Goddard designed new stereographic cameras specifically for air photo reconnaissance, developed a portable film processing laboratory, and even drew up plans for a new specialized reconnaissance aircraft. [3] Realizing the political and fiscal restraints on military research and development, Goddard used peacetime aerial mapping to test his methodologies. In July of 1934, the Army Air Corps staged a flight of 10 Martin B-10 bombers from Washington DC to Fairbanks, Alaska. Although the primary intent of the mission was to showcase airpower, the flight also mapped 30,000 square miles of Alaskan territory en route using Goddard’s new cameras and photogrammetric techniques. [4]

While Goddard used peacetime practicality to sell his reconnaissance theories in the United States, the mood in Europe was decidedly different. The rise of Adolf Hitler and Nazi Germany in the early 30s resurrected Nationalism and political discord not felt since the Great War. In response to rising tension and the portent of armed conflict, the French began flying covert photographic reconnaissance missions over western Germany in 1936. [5] In Britain, the leading proponent of aerial reconnaissance was RAF Wing Commander Frederick W. Winterbotham, Chief of Air Intelligence in the Secret Intelligence Service. Winterbotham lobbied tirelessly throughout the Air Ministry for resources to conduct aerial reconnaissance of Germany’s growing military and industrial infrastructure. Needing an ally to oversee actual flight operations, Winterbotham recruited Frederick Sydney Cotton, an Australian pilot with extensive aerial reconnaissance experience during World War I. [6] With Winterbotham’s assistance, Cotton procured a Lockheed A-12 Super Electra and made extensive modifications to turn the twin-engine, civilian aircraft into an airborne intelligence collection platform. Extra fuel tanks were installed to increase range, and a concealed, remotely controlled opening was built into the bottom of the fuselage. Three cameras were installed, one mounted vertically and two set at an angle to take oblique photographs. All three cameras could be operated from the pilot's control wheel. [7] In the spring of 1939, Cotton flew 15 covert missions over targets in Germany, Italy, and the Mediterranean. Winterbotham used the successful mission to rationalize the need for a new high-altitude reconnaissance aircraft with the speed, climb, and ceiling to avoid enemy fighters and anti-aircraft defenses in time of war. [8] Predictably, Winterbotham’s appeal fell on deaf ears at the Air Ministry.

While Cotton diligently photographed German and Italian facilities in Europe and North Africa, the Germans were engaged in aerial intelligence gathering of their own. The German secret reconnaissance unit was under the command of Lt. Col. Theodor Rowehl, himself a former reconnaissance pilot in World War I. Rowehl began flying reconnaissance missions as a civilian working for the Abwehr, the German military intelligence organization. He used a Heinkel He 111 aircraft with the civil markings of Deutsche Luft Hansa Airline (now Lufthansa) to covertly collect photographic images over British and French territory. [9] A more concerted Abwehr effort was directed towards the Soviet Union, their closest ally at the time. Rowehl, now a commissioned officer in the Luftwaffe Air Intelligence Branch, directed almost 500 long-range flights over Soviet airspace using specially modified Dornier Do 17 reconnaissance aircraft to pinpoint Soviet airfields, transportation arteries and railheads. One of Rowehl’s Dornier spy planes even crashed inside the Soviet Union complete with cameras and exposed film, but Stalin was blinded by his false alliance with Germany and did not realize the stray Nazi aircraft was part of a larger effort to prepare for Hitler's planned invasion. [10]

In September of 1939, as the tide of war once again broke across the continent of Europe, the intelligence component of each militarized nation included a small and innovative core of aerial reconnaissance professionals, but the dedication and enthusiasm of pre-war air intelligence proponents concealed a significant shortfall of equipment, personnel and resources. How each nation’s military developed and implemented strategic reconnaissance and air photo interpretation would have a significant influence on the war’s outcome.

The Royal Air Force Shows the Way

At the start of the war, the RAF did not have a specialized photo reconnaissance aircraft. RAF doctrine assigned long range reconnaissance to the twin-engined Bristol Blenheim bomber which had a top speed of 266 mph and a maximum ceiling of 24,000 feet. Short range reconnaissance was handled by the aging Lysander army cooperation aircraft with an even more pedestrian speed of 230 mph. [11] Neither aircraft had the slightest chance of penetrating a German airspace teeming with ME-109 interceptors. Such was the mortality rate among early reconnaissance flights that Fred Winterbotham and Sydney Cotton, now an RAF Flight Commander, reiterated their call for a specialized reconnaissance aircraft. [12] In 1939, the only RAF aircraft with the speed, ceiling height and dependability to conduct long range strategic reconnaissance missions into German airspace and return unmolested was the Supermarine Spitfire, the mainstay of Britain’s air defense. Winterbotham and Cotton took their appeal for a Spitfire reconnaissance aircraft directly to Air Marshall Hugh Dowding, the powerful Commander in Chief of RAF Fighter Command. [13]

The odds were against Dowding authorizing Spitfire aircraft for reconnaissance work. Britain was bracing itself for the storm to come, and every Spitfire would be a valuable commodity against a Nazi war machine that had already pulverized Poland and was postured to repeat their 1914 sweep across Belgium. Fortunately, Dowding was one of the more visionary military commanders of the era. In the years preceding World War Two, he was a driving force behind Britain’s development of both the Spitfire and Hawker Hurricane fighters, and in establishing the Radio Direction Finding Stations we now know as RADAR. [14] After carefully weighing the merits of the request, he responded by saying “I begrudge giving up any Spitfire, but I must take a broader view of the question.” [15] On October 16 1939, Air Marshall Dowding released two new Spitfires for dedicated reconnaissance operations. [16]

Sydney Cotton immediately launched into a major modification of the precious Spitfires. Each Spitfire was stripped of guns, radio and all unnecessary equipment, thus reducing its total weight by 450 pounds. The gun ports were sealed, and any joint or gap in the fuselage was filled with plaster in order to make the aircraft as aerodynamic as possible. [17] The engines were also modified to optimize performance at very high altitude and give the reconnaissance Spitfires an effective ceiling of up to 40,000 feet. To improve visibility, the cockpit canopy was replaced by a sliding hood with a teardrop shaped blister on each side. Two F24 cameras with 5 inch lenses were mounted vertically within the wings and synchronized to provide two, slightly overlapped photos. [18] Finally, Cotton painted his aircraft a pale shade of blue to make the plane less conspicuous to an observer looking from below. [19] On 18 November, a Spitfire completed its first photo reconnaissance mission over Aachen, Germany. Low cloud cover prevented the pilot from collecting any useful photos, but the speed, altitude and maneuverability was everything Witherbotham and Cotton hoped for. [20] The RAF had found its first specialized reconnaissance platform.

An RAF Photographic Reconnaissance Spitfire in flight

Although the first two Photo Reconnaissance Spitfires proved the concept, they also revealed problems and issues with both process and equipment. First, operating at high altitude often resulted in frozen cameras, fogged lenses or cracked film. RAF engineers solved this problem by ducting hot air from the engine through the camera bays. [21] Second, a Spitfire lacked the range to penetrate deep into German held territory. The overall weight of the aircraft was definitely a consideration, but since rate of climb was not considered critical, it was felt an adequate tradeoff would be to install an extra 29 gallon fuel tank within the fuselage. Later iterations of reconnaissance Spitfires had greater fuel capacity within the wings and also carried a 70 gallon drop tank. [22] In all, thirteen versions of reconnaissance Spitfires were produced, each building on the range, ceiling and collection capability of its predecessor. By the end of the war, reconnaissance Spitfires enjoyed an effective range of over 2000 miles, a service ceiling of 42,600 feet, and a top speed of 445 mph. [23] The only interceptor in the Luftwaffe arsenal that could even touch it was the Messerschmitt Me-262 jet fighter, but it was introduced too late in the war and in too few of numbers to be a factor. [24]

A final problem identified by the prototype Spitfires concerned the quality of photography rather than the aircraft itself. From 40,000 feet, a 24-inch focal length camera with a 5 inch lens simply did not provide a photograph of sufficient clarity and detail. [25] A 36 inch focal length camera was available, as were lenses in 8, 14 and even 20 inch varieties, but the basic principles of photography prohibited a quick or easy solution to the problem. In photography, the longer the focal length of a camera, the greater the scale and detail of the image. However, a longer focal length also means that a smaller area is being captured in each photograph. Another factor that affects the clarity of an image is the physical size of the film negative. A larger film negative provides a higher resolution image, but it also requires a larger camera and limits film capacity. To overcome these technical tradeoffs, air reconnaissance missions were flown at various altitudes, with different types of cameras fitted with lenses of differing lengths. [26]

The overwhelming majority of Spitfire reconnaissance sorties collected photographs vertically from high or very high altitude, but when an air photo suggested the presence of a significant target, it often necessitated a second, more detailed photo be taken from low altitude for verification. [27] Low level sorties were also required due to a low cloud ceiling. The dangers of low level air reconnaissance were obvious: it put the aircraft back in range of anti-aircraft guns, and below the watchful gaze of German fighters who circled like hawks above high value targets. To improve the odds of low level reconnaissance, the RAF developed a new version of Spitfire designed specifically for the mission. The Mk VII carried the eight machine guns of a standard Spitfire, but with an extra fuel tank inside the fuselage. It had one obliquely mounted camera that could turn 90 degrees left or right of the aircraft, and two vertically mounted cameras with lenses of varying length. Finally, it was painted a solid shade of pale pink to help disguise it against a low cloud bank. [28] 45 Mk VIIs were produced and they collected an abundance of valuable intelligence, but their routine sorties were among the most hazardous missions of the war.

Air Photo Interpretation

While the RAF was forging new reconnaissance methods and capabilities in the air, an equally important aspect of strategic intelligence was being developed in the remote village of Medmenham, England. Hidden within a stately estate house was the headquarters of the British Military Intelligence (MI4) Central Interpretation Unit (CIU). [29] The CIU had been formed in the late 1930’s for the expressed purpose of deriving strategic intelligence from reconnaissance photography. The British Air Ministry recruited talented individuals from a broad range of civilian occupations such as teachers, geographers and archaeologists to serve as photo interpreters, and developed an intense curriculum of air photography training. Winston Churchill’s daughter Sarah served throughout the war at Medmenham as a skilled intelligence analyst. [30]

The strategic value of the intelligence derived through CIU air photo interpretation methods cannot be overstated. In 1940, after the British Expeditionary Force evacuated the continent from Dunkirk and as the Battle of Britain raged, the only option for retaliation left open to the British was RAF air strikes against economic and military targets in German occupied territory. However, the premium placed on Strategic bombing by pre-war air advocates fell far short of Bomber Command’s actual ability to identify, select and destroy significant targets. [31] Without the structured, methodical identification of targets provided by CIU analysts, RAF air strikes would have little value.

Perhaps the most vivid example of a sustained strategic bombing campaign whose success hinged on air photo reconnaissance and interpretation was Operation Crossbow, the Allied plan to destroy German V rocket production and launch sites along the Baltic coast. In late 1942, MI4 became aware of a secret weapon production facility somewhere near Peenemunde, Germany. The area became a frequent subject of interest for photo reconnaissance missions, and on June 23, 1943 the relentless scrutiny paid off. A routine photo captured a long, cylindrical object on a flatbed trailer parked outside of a mysterious facility. [32] It was the Allies’ first glimpse of the dreaded V2 rocket designed to terrorize London and major population centers. On August 17 and 18, the British deployed over 500 Lancaster and Halifax bombers to drop nearly 36,000 tons of explosive bombs on the Peenemunde rocket facility. The RAF and USAAF would stage three more raids of V weapon production facilities over the next year, each proceeded by intense photo reconnaissance in order to select precise targets, and each followed by thorough Bomb Damage Assessment (BDA) flights. [33]

June 23, 1943, a watershed moment in air photo interpretation history; an RAF reconnaissance sortie detects a German V2 rocket in transit.

German Growing Pains

While British collaboration, innovation and unbiased thinking paid huge dividends for the RAF, the German experience was much different. Despite the early aggressiveness of Rowehl and the air reconnaissance unit, the German Luftwaffe remained mired in the politics and compartmentalization that characterized the Nazi system. Hermann Goering himself had very little interest in air photo reconnaissance. [34] The Luftwaffe Air Intelligence Branch was given very little latitude to pursue new technologies and techniques, and German Air Intelligence officers were often given additional duties such as propaganda and censorship. [35] The Luftwaffe also had very unique political baggage that restricted the independence of strategic reconnaissance operations. The principles of Blitzkreig, the “lightning war” that so easily overran Poland, Belgium and France, mandated extremely close coordination of ground and air operations. [36] It can even be argued that the Luftwaffe’s primary reason for existence was support of ground forces. This is the reason they never developed the heavy strategic bombing capability they lacked during the Battle of Britain, and it was the reason Luftwaffe Air Intelligence focused almost exclusively on tactical, rather than strategic intelligence. Germany simply had no systematic air photo interpretation equivalent to MI4’s CIU. [37]

Nevertheless, Rowehl and his reconnaissance unit flew tactical intelligence collection missions over Allied territories with whatever resources the Nazi war machine would provide. An assortment of Junkers Ju 88's, Dornier Do 17's and Messerschmitt Bf 110's were used to fly photo-reconnaissance sorties. [38] In contrast to the RAF philosophy of using a stripped down, high-performance Spitfire for high altitude reconnaissance, the Luftwaffe applied very few modifications to their reconnaissance aircraft, and flew fully armed in order to drop bombs on targets of opportunity. [39] As the war progressed, the British air defense system virtually eliminated Luftwaffe reconnaissance flights over Britain until September of 1944 when the Germans unveiled the Arado Ar 234, a jet powered strategic bomber and reconnaissance platform with the speed and ceiling to penetrate British airspace. [40] Even then, Luftwaffe Air Intelligence tended to restrict reconnaissance flights to pre-raid tactical collection and post-raid BDA missions. [41]

The American Experience

When the United States Army Air Force (USAAF) entered the European air war they also lacked an aircraft designed specifically for aerial reconnaissance, and like their British counterparts before them, the Americans learned from bitter experience the value of having an aircraft with the speed, altitude and range to avoid enemy fighters. [42] The earliest American attempt to replicate Spitfire reconnaissance capabilities was the F-4, a factory modified Lockheed P-38 which replaced the Lightning’s guns and cannon with four high-quality reconnaissance and mapping cameras. The F-4 had inherent speed, altitude and range qualities, and was a favorite of both pilots and maintenance crews. In all, over 200 F-4 and F-5s based on the P-38 would be produced, and hundreds more stock P-38s were field modified to accommodate photo reconnaissance. [43] In mid-1943, the North American P-51 Mustang arrived and quickly established itself as the premier air superiority fighter of the war. Its reconnaissance variant, the F6, eventually became the dominant reconnaissance model flown by the USAAF in Europe. [44]

The USAAF also organized their air photo interpretation doctrine based on RAF procedures and tactics. [45] US photo-reconnaissance operations in Europe were based at RAF Mount Farm airfield near Dorchester, England. Photography from USAAF flights was transferred to Medmenham where US Army photo interpreters worked and trained alongside more experienced CIU interpreters. [46] One significant American contribution to air intelligence was the development of nighttime air photo reconnaissance. In 1939, the U.S. Army Air Force asked Professor Harold Edgerton of the Massachusetts Institute of Technology to design a flash lamp strong enough to enable nighttime aerial photography. Edgerton, who had earlier developed a high-speed Strobe light to freeze motion in scientific experiments, spent the next four years developing and testing a flash unit thousands of times more powerful than his original Strobe. [47] Thanks to the Edgerton flash unit, nighttime reconnaissance provided vital intelligence about enemy strengths and troop movements to both USAAF and RAF planners. By 1943, American reconnaissance efforts had grown substantially in both quality and quantity, and the close collaboration between USAAF and RAF photo reconnaissance units helped ensure success in the combined strategic bombing campaign.

Air Reconnaissance in the Pacific

In Europe, American air reconnaissance had the luxury of an experienced and supportive mentor. The situation in the Pacific was entirely different. Although the British had territorial possessions throughout the South Pacific, they had not performed the meticulous baseline reconnaissance of Japanese military facilities and infrastructure as they had the Germans. The security conscious Japanese kept an extremely tight lid on any potential intelligence about their home islands, and there was virtually no pre-existing information available on the location of the most lucrative strategic targets. [48] The great distance across the Pacific was a tremendous obstacle. After the American airfields on Wake Island and Luzon were lost in the early months of the war, most strategic points of interest were beyond the range of all but carrier borne aircraft. From a strategic reconnaissance perspective, the Allied task was daunting.

Fortunately, the Americans were not alone in their Pacific mission. Both the Royal Australian Air Force (RAAF) and Royal New Zealand Air Force (RNZAF) had well established air reconnaissance capabilities throughout the South Pacific. Flying an assortment of bi-planes, converted cargo transports and flying boats, the RAAF and RNZAF made up for equipment shortfalls with sheer determination and vigilance. Australian and New Zealand reconnaissance squadrons patrolled the sea lanes and coastal shores of Japanese held islands, and diligently carried out search and rescue missions for downed Allied airmen. [49] The Australians also pioneered the concept of airborne forward air control, coordinating close air support for ground forces directly from overhead reconnaissance aircraft during the hectic jungle battles of New Guinea. [50] All of these low-level reconnaissance missions were performed at great peril, especially early in the war when the Japanese enjoyed almost total air superiority.

The American air reconnaissance effort was initially limited to blind tactical forays across vast stretches of ocean in search of Japanese naval forces. The random nature of tactical air reconnaissance missions in the Pacific left much to fate and chance. Perhaps the most prominent example of air reconnaissance in the Pacific, and one that illustrates both the luck and importance associated with tactical air reconnaissance, is the American victory at Midway. On June 3 1942, a Japanese Aichi E13A "Jake" reconnaissance plane from the cruiser Tone located the US fleet about 200 miles northeast of Midway, but failed to report the presence of American aircraft carriers. Simultaneously, a Douglas SBD torpedo bomber from the carrier USS Enterprise found the Japanese fleet and fixed it for immediate attack. [51] The resulting time delay between strikes and counter strikes proved critical to the outcome of the battle.

The first true US strategic reconnaissance capability in the Pacific began in April of 1942 when Capt. Karl L. Polifka established the 8th Photographic Squadron at Port Moresby in New Guinea. Polifka had been allocated five F-4’s specially modified with additional fuel tanks. Unfortunately, due to weather and mechanical failure only one F4 made it beyond a staging base in Australia, but with his lone F-4 Polifka almost single-handedly mapped the area surrounding New Guinea and New Britain. It was an extremely grueling mission due to the long distances and unpredictable weather, but the results were invaluable during MacArthur’s New Guinea campaign of 1943. [52] Later in the war, the USAAF introduced the F-13, a modified Boeing B-29 Superfortress designed specifically to conduct long range aerial reconnaissance. On Nov. 1, 1944, an F-13 flew a 14 hour mission from Saipan to Tokyo at an altitude of 32,000 feet, the first US aircraft to fly over Tokyo since the Doolittle raid in April of 1942. Once the US established air supremacy in the Pacific, F-13s flew hundreds of missions over the Japanese mainland, and mapped virtually every significant target in Japan. [53]

A P-38 reconnaissance variant being prepped for a mission at Saipan’s East Airfield. Note the camera bays on the side and bottom of the central nacelle that have replaced the nose armament.

For their part, the Japanese did appreciate the value of air reconnaissance. Japan boasted a well developed aviation industry and produced excellent quality specialized reconnaissance aircraft such as the Kawanishi H8K "Emily" and the Mitsubishi Ki-46 "Dinah".[54] Prior to the war, the Japanese performed meticulous aerial mapping of Malaysia and the Philippines, but narrow minded thinking and bitter inter-service rivalry prohibited the Japanese from fulfilling their full potential in air reconnaissance. Japan actually had two distinctly different air services; one under the direction of the Army and one a component of the Navy. [55] To say that the Japanese Army and Navy did not cooperate and share information is a major understatement. In fact, their relationship was overtly hostile. There was no exchange of strategies, intelligence or resources in the Japanese military, and in both cases the primary mission of their respective air service was to support the tactical requirements of the parent. [56] In the end, once the Japanese lost air superiority their reconnaissance aircraft were far too vulnerable to American fighters to be effective.

Airborne Intelligence Comes of Age

Aerial reconnaissance and air photo interpretation played a huge role in the Allied victories in both the European and Pacific theaters, but they were by no means the only forms of intelligence derived through airborne collection methods. World War Two also saw dramatic advances in electronic warfare. Signals Intelligence (SIGINT), the science of using radio waves and electromagnetic energy to detect electronic signals, includes two unique intelligence disciplines; Electronic Intelligence (ELINT) is the process used to detect and analyze enemy radar and electronic navigation emissions, and Communications Intelligence (COMINT) refers to the interception and decoding of enemy radio communications. [57] Once again it was the Allies who took the lead in the exploitation of airborne SIGINT. Flying a variety of specially modified aircraft collectively known as “Ferrets,” USAAF and RAF flight crews collected valuable intelligence on the location and capability of enemy radar stations, and the presence and bearing of German radio navigation beacons. [58]

One of the more celebrated intelligence successes of World War Two was code name “Ultra,” the British operation to detect and decrypt German signals traffic. The fact that British Intelligence had access to Germany’s communication code was one of the most closely guarded secrets of the war. The British were very cautious in deciding when to use the information they derived from Ultra, lest the Germans become aware that their secret code had been broken. It was none other than Fred W. Winterbotham, the RAF Squadron Leader who had done so much to advance the cause of aerial reconnaissance at the start of the war, who was in charge of deciding who would receive intelligence gleaned from Ultra, and when they should receive it. [59] Winterbotham often tasked reconnaissance sorties over areas of interest identified through Ultra decrypts. If the Germans saw a British reconnaissance aircraft pass over that particular area, they would assume the British discovered their knowledge through air photo interpretation rather than Ultra. Thus, air reconnaissance helped preserve the secret of Ultra, and on several occasions the imagery brought home for analysis helped verify the accuracy of the Ultra decrypt. [60]

Leaving Their Own Legacy

No discussion of aerial reconnaissance during World War Two would be complete without a word about the pilots and air crews who flew the actual air missions. Sitting alone in a freezing cold cockpit for hours at a time, wartime air reconnaissance pilots risked death every time they took off on a mission. Navigation was a special challenge for reconnaissance pilots. Flying without radio contact, the pilot had only a map and a compass to find his way deep into enemy airspace, locate his assigned targets, and return safely to his point of origin. Each weather situation had its inherent danger. A pilot might have to fly above a cloud bank for hours without seeing a landmark, or he might have to burn fuel reserves flying an endless zigzag pattern when the weather was clear. Fuel was a constant consideration. A pilot had to monitor the fuel gauge and continually calculate fuel consumption rates in order to return home safely.

The extremely high altitude required of a typical reconnaissance flight held other unique challenges. Prior to the war, very few pilots had any experience flying above 20,000 feet. [61] At 35,000 feet, the new reconnaissance pilot suddenly found himself trying to manipulate aircraft controls in a sub-arctic environment where the temperature could easily fall to 50 degrees below zero. Pilots often wore so many layers of clothing that they had to be hoisted into the aircraft by helpful ground crews. [62] Oxygen deprivation was another constant hazard of high altitude flight. Oxygen masks and filtration systems were very primitive in 1940, and hypoxia, a loss of consciousness or coherence due to oxygen deprivation, was a very real danger. [63] If the cold and altitude sickness weren’t enough, an even greater peril of high altitude missions was the condensation trail that could appear at any time behind the aircraft. A contrail sent an open invitation to enemy fighters. If an air predator could not climb to reconnaissance altitude in time to engage, it would certainly be waiting on the return flight. Reconnaissance pilots even attached mirrors to their canopies in order to spot the dreaded contrails and drop below condensation altitude as quickly as possible in order to dissipate the telltale white ribbon dragging behind the aircraft. [64]

The dangers of low level reconnaissance are legendary. Only the most experienced pilots were selected for low level reconnaissance sorties, usually against high priority coastal targets protected by an umbrella of anti-aircraft guns and interceptor aircraft. It is a testament to the courage and daring of reconnaissance pilots that low level assignments were the most sought after, and most volunteered for, of all reconnaissance missions. [65]

A low-level, oblique reconnaissance photograph of a German radar installation at Auderville, France, taken on February 22, 1941 using an F24 side-facing camera.


The Second World War has been called “the last good war”. In the United States and Allied Nations, we remember World War Two as a great human effort of tireless work, brilliant thinking, incredible risk and collaborative spirit. Air reconnaissance in World War Two was all of that, and a critical element in an Allied victory that at times seemed improbable.
* * *

Show Footnotes and Bibliography
* * *

Copyright © 2012 Del C. Kostka

Written by Del C. Kostka. If you have questions or comments on this article, please contact Del Kostka at:

About the author:
Del C. Kostka is a staff officer at the National Geospatial Intelligence Agency in St. Louis, Missouri. He has a Masters Degree in Operational Arts and Military Science from the US Air Force Air Command and Staff College.

Published online: 07/07/2012.
© 2018, LLC Contact Brian Williams at: