Aircraft reconnaissance

A reconnaissance aircraft is a military aircraft designed or adapted to perform aerial reconnaissance. Their roles include collection of imagery intelligence (such as photography), signals intelligence, and measurement and signature intelligence. In addition to general intelligence gathering, modern technology has also enabled some aircraft and UAVs to carry out real-time surveillance.

In years prior to the development and common use of sophisticated electronic sensors (such as radar) and image recording devices, reconnaissance aircraft were also relied upon by military forces for distant visual observation and scouting of enemy movement. An example is the PBY Catalina maritime patrol flying boat used by the Allies in World War II: a flight of U.S. Navy Catalinas spotted part of the Japanese fleet approaching Midway Island, beginning the Battle of Midway.

Prior to the 20th century machines for powered and controllable flight were not available to military forces, but some attempts were made to use lighter than air craft. During the Napoleonic Wars and Franco-Prussian War, balloons were used for aerial reconnaissance by the French.

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