Aerial reconnaissance in World War I

During 1914-18, driven primarily by the introduction of heavier-than-air aircraft, aerial reconnaissance developed from an almost zero baseline to a vast, complex science. Equipment, tactics, procedures and terminology that would survive with modifications to this day had their origins in this period.

The first use of an airplane in war was a reconnaissance flight performed on 23 October 1911 by Captain Carlo Maria Piazza in a Blériot XI during the Italo-Turkish War in Tripolitania. Military aerial photography began that December. The experience in World War I would begin on very similar terms, with French Bleriot and German Taube monoplanes. Reconnaissance was widely perceived as the only practical use of airplanes.

While most of the combatant countries possessed a few military aircraft in August 1914, these were almost exclusively devoted to reconnaissance and artillery spotting, supplementing well-tried and familiar platforms like balloons and kites. Tethered balloons could ascend to as high as a mile, but were easy to shoot down. Furthermore, they were unstable observation platforms in any wind, leading to attempts to stabilize them with kite-tails or drogues attached to the basket. Dirigibles like the huge new German Zeppelins were considered the best reconnaissance platforms and they served effectively for maritime patrols. Vertical camera installations were used from the beginning of the war, but they were too heavy and bulky for light airplanes, and most early reconnaissance from airplanes consisted of visual observation and written reports. Handheld cameras were widely used but with disappointing results. Good photographs required both skilled flying and an operator who could devote time to handle the camera and the unwieldy and heavy glass plates it required. In time, longer focal length lenses were used, cameras and gear grew lighter and bigger, and for survival, operating altitudes increased up to the 12-18,000 foot level. Driven high, aircrews began to use oxygen and heated clothing items.

The critical discipline of communicating results led to rampant improvisation. At first it was not uncommon for aircraft to land next to command posts so the pilot could personally pass on urgent information. For artillery spotting, time was of the essence, and the French tried air-dropped messaging, colored flares, and pre-arranged aircraft maneuvers to convey information. France was reportedly the first to try airborne radios, often transmitters alone due to the weight penalty; others maintain that Britain preceded with the light-weight Sterling radio set in aircraft by 1915.

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Wikipedia