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First military observation -

The world's first military observation balloon, L'Entreprenant, was launched on June 26, 1794 by the French Republican Army to observe the combined Austrian and Dutch army during the Battle of Fleurus. This became the first battle to be won through control of the air.

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Looking down on the American Civil War -

The idea of using observation balloons was revisited during the American Civil War, when both sides deployed them. Here, the Union Army balloon Intrepid is seen being inflated from a hydrogen gas generator for the Battle of Fair Oaks, also known as the Battle of Seven Pines, which took place between May 31 and June 1, 1862, in Henrico County, Virginia.

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Pigeon photographer -

In the early 20th century, pigeon photography was introduced by the German chemist Julius Gustav Neubronner (1852–1932). He'd previously been using pigeons to deliver medications, but in 1907 he had the idea of attaching a lightweight, time-delayed miniature camera to the birds. Initially employed to take aerial photographs during peacetime, deploying pigeons to capture images during conflict proved difficult, although they were used extensively to deliver messages. And in any case, aerial reconnaissance using aircraft was just taking off.

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Early aerial reconnaissance -

Pictured here is one of the first wartime aerial photographs ever taken. It was snapped in 1911 over Libya during the Italo-Turkish War. The conflict is known for the first-ever dropping of an aerial bomb from a heavier-than-air aircraft.

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First reconnaissance flights in Europe -

In October 1912, a Bulgarian Albatros military aircraft (pictured) performed one of Europe's first aerial reconnaissance sorties during combat conditions against the Turkish lines on the Balkan Peninsula, during the Balkan Wars of 1912–1913.

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First World War -

The use of aerial photography was embraced widely by all sides during the First World War. At the start of the conflict, tethered observation balloons and surveillance blimps (airships) were used to reconnoiter the battlefield.

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A perilous task -

An artillery observer's task was a perilous one. Suspended under a fabric envelope filled with helium, he was at the mercy of enemy fire and capricious weather.

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The advent of aerial reconnaissance -

The French had incorporated cameras in airplanes at the very start of the war, and were considered pioneers in aerial reconnaissance. This image  shows the deep trenches of German lines plus mine and shell crater locations.

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Skill and competence -

By mid-1914, aircraft were increasingly being used for reconnaissance and artillery spotting. Cameras were heavy and bulky, and capturing good photographs required both skilled flying and a competent operator, who could work effectively even under fire. Here, a sergeant of the Royal Flying Corps demonstrates a C type aerial reconnaissance camera fixed to the fuselage of a BE2c aircraft.

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A player in the theater of operations -

Aerial reconnaissance was vital in observing troop movements and, on many occasions, the direction and velocity of a poison gas attack. Pictured is a chemical assault by German forces on the Eastern Front.

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Aerial survey duties -

With the cessation of hostilities, aircraft were used extensively by victorious Allied powers to survey the devasted landscape of Europe as an aid to correcting and improving maps.

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Second World War -

By the outbreak of the Second World War, advances in aviation and photographic technology was such that airborne reconnaissance saw new tactics and new procedures employed to become a vital, indispensable component of air power. Pictured is a member of the Royal Navy's Air Arm Fleet operating a mounted camera during a flight.

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Hiding in plain sight -

The Royal Navy Air Arm exposed the hiding place of the German battleship Tirpitz, moored in Narvik-Bogen Fjord, Norway, in this July 17, 1942 photograph.

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No. 1 Photographic Reconnaissance Unit -

It soon became apparent to Allied powers that airborne reconnaissance was better suited to small, fast, and highly maneuverable aircraft. Formed in 1940, the No. 1 Photographic Reconnaissance Unit (or 1 PRU) was a flying unit of the Royal Air Force (RAF). The unit was equipped with a variety of aircraft modified for the photographic reconnaissance role, including Supermarine Spitfires, Bristol Blenheims, Lockheed Hudsons, and de Havilland Mosquitos. Pictured is a 1 PRU Spitfire in blue livery for camouflage. This was a long range, high-altitude reconnaissance variant of the iconic fighter plane. They were stripped of many of their components, including armory. The pilots often flew without any fire power!

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Uncovering Peenemünde -

It was reconnaissance carried out by Spitfires that led to the discovery at Peenemünde in 1943 of the research center developing Hitler's V-1 and V-2 rockets. The photographs pinpointed the exact position of the facility, which was subsequently bombed by the RAF.

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Rocket sites destroyed -

Their cover blown, the Germans relocated the rocket research installations to northern France, where they eventually launched the V-1 and V-2 flying bombs, which targeted cities in England and in other European countries. Again, thanks to Allied reconnaissance, these sites were also destroyed.

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The Mosquito -

The British de Havilland Mosquito DH. 98 (pictured) excelled in the photo-reconnaissance role. Another aircraft favored by 1 PRU, specially adapted Mosquitos—in 1941, one of the fastest operational aircraft in the world—were often deployed to undertake reconnaissance roles as well as being used as effective bombers. Pictured is a Mosquito banking to show the aerial camera ports under the fuselage.

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Dambusters -

Aerial reconnaissance played a major role in determining the precise flightpaths Lancaster bombers needed to follow in order to strike the Mohne, Sorpe, and Edersee dams during the May 16–17, q943 attack known as Operation Chastise. This was the famous Dambusters Raid, one of the most audacious military operations of the war.

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USAAF reconnaissance -

Reconnaissance aircraft from the United States Army Air Forces were among those flying sorties over northern France in the run-up to D-Day. Pictured is Lockheed F-5 Lightning marked with invasion stripes to help Allied troops clearly identify it as an friendly aircraft.

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Above the beaches -

The aerial reconnaissance photographs of Utah Beach (pictured) and the other beaches earmarked for landing were critical in identifying German defensive positions.

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Discovering the camps -

Using sophisticated, modern photo analysis techniques on Second World War aerial reconnaissance film, two CIA analysts produced the only known photographs of the Birkenau extermination unit at the Auschwitz concentration camp. The photo raised the question of why the camp wasn't bombed in August 1944, when this picture was made.

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Reconnoitering the Korean war -

Second World War-era Stinson L-5 Sentinel's were used as observation planes by the United States Army Air Forces throughout the Korean War to reconnoiter enemy positions. Though the aircraft was quiet in flight, it was slow and presented a prized target for communist anti-aircraft guns.

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Cold War reconnaissance -

Aerial reconnaissance uncovered the Soviet Union's attempt to install missiles on Cuba during what became known as the Cuban Missile Crisis of October 1962. This photograph clearly shows a medium range ballistic missile base in San Cristobal. It's been labeled detailing various areas of the facility.

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Cuban Missile Crisis -

With irrefutable photographic proof of deployment—and after knife-edged Soviet, Cuban, and American saber-rattling—the Russians withdrew their missiles. This images of the cargo vessel Anosov transporting its deadly payload back to the USSR provided further proof that Khrushchev was arming Castro.

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U-2 spy plane -

After World War II and during the Cold War, the United States developed several dedicated reconnaissance aircraft designs, including the U-2 and SR-71, to monitor the nuclear arsenal of the Soviet Union. In 1960, a U-2 spy plane was shot down by the Soviets while on a top secret aerial reconnaissance mission.

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U-2 Incident -

In what became known as the U-2 Incident, the plane's pilot, Francis Gary Powers, was tried by a court in Moscow and convicted of espionage. He was sentenced to three years imprisonment and seven years of hard labor. Powers was freed on February 10, 1962, exchanged for Soviet intelligence officer Rudolf Abel in West Berlin.

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Monitoring the Vietnam War -

The Cessna L-19 Bird Dog was a reconnaissance plane used by American forces during the Vietnam War. Despite its exceptional maneuverability, 469 Bird Dogs were lost during the conflict, with few pilots surviving a downing.

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Role of the Bird Dog -

Bird Dogs were used to position concentrations of Viet Cong. They were also used to report on bombing raids. In this image, the remains of a workshop and truck shelter, bombed by US and South Vietnamese forces in response to a Vietcong attack on two American cantonment areas in the south, is checked for damage.

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Fastest and highest -

Developed from the Lockheed A-12 reconnaissance aircraft during the 1960s, the US Air Force SR-71A, also known as the "Blackbird," was a strategic reconnaissance plane built by Lockheed. It once held the record as the world's fastest and highest flying operational aircraft. The USAF permanently retired it in 1998.

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Launch of the UAV -

Since the 1980s, militaries around the world rely upon assets other than manned aircraft to perform aerial reconnaissance. The unmanned aerial vehicle (UAV) ScanEagle is typical of today's reconnaissance technology. One is pictured here on its catapult prior to launch in Iraq. UAV's are designed for surveillance and intelligence gathering.

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Era of the spy satellite -

Today, aerial reconnaissance for military purposes is mostly carried out by multi-million-dollar satellites. Pictured in 2020 is the United Launch Alliance Delta IV-Heavy rocket taking off from Cape Canaveral. The rocket is carrying a classified spy satellite for the National Reconnaissance Office.

Sources: (HistoryNet) (Defense Media Network) (NPR) (Britannica)

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