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Salmson 2A2 of the 91st Aero Squadron

Martin aircraft carrying explosives.

DeHavilland DH-4

The Ostfriesland under attack in 1921 Army-Navy bombing test. Mining effects of hits like this sank her.

Aerial Reconnaissance in World War I

The French had first used balloons for reconnaissance during the Napoleanic wars and later in the Franco-Prussian War. So aerial reconnaissance was a strategy that was familiar to them, and it was natural that they would use aircraft for this purpose as planes became able to perform that function.


From the first days of World War I, the airplane demonstrated its ability to be the "eyes of the army." As the British Expeditionary Force (BEF) retreated from German invaders in France, the roughly two-dozen reconnaissance airplanes of the Royal Air Force watched from above. On August 22, 1914, British Captain L.E.O. Charlton and Lieutenant V.H.N. Wadham reported that German General Alexander von Kluck’s army was starting to prepare to surround the BEF, contradicting all other intelligence. The British High Command listened to the pilots’ report and started a retreat toward Mons--destroying morale but saving the lives of 100,000 soldiers.


A week later, French aerial reconnaissance units began reporting that the Germans were moving toward the east of Paris. Although the intelligence officer refused to listen, General Joseph-Simon Gallieni, the military commander of Paris and a supporter of aviation, did. He issued orders sending French troops to the exposed German flank. The resulting First Battle of the Marne was a victory for the French because it forced the Germans away from Paris. Meanwhile, on the Eastern Front in Poland, aerial reconnaissance reports on the movements of the Russian Army helped the Germans and Austrians stop an advance at the Battle of Tannenburg. But the result of these two battles was to push the armies fighting on both fronts into defensive positions in the trenches--a stalemate that would last almost until the end of the war.


As both fronts of the war settled into the mud of the trenches, the pilots started to develop their roles. In two-seater airplanes such as Bleriot XI-2s and Rumpler Taubes, they were able to fly over enemy lines and bring back reports on enemy positions, the locations of munitions, and the movements of supplies and reinforcements. But there were still problems. The officers on the ground were not always willing to listen to the observations of pilots, who sometimes exaggerated what they saw. Some aerial observers accidentally reported on the wrong army, since all muddy soldiers looked the same from above. One German pilot even reported that an English unit was running around in disarray and with a sense of great panic. They were playing soccer.


There were also problems communicating aerial observations. Ideally an airplane could land and the crew could deliver an observation in person, but it was not always possible to find a suitable landing location near the proper officer’s unit. Some units devised systems of having messages dropped in weighted bundles, but many of the notes blew away, landed in trees, or were ruined in the mud. Other units invented signal systems based on airplane position and movement, but these were frequently misinterpreted. By 1915, mechanics began to add wireless telegraph equipment that could send messages to the ground in Morse Code to the airplanes.


Reconnaissance airplanes held two people--the pilot and the aerial observer. The observer would often sketch the scene of the ground below. Soon, some English observers thought it would be easier and more accurate to use their cameras to photograph the enemy lines. This idea was quickly seized upon and copied by the aerial observers of all the nations. The maps that were used by both sides for the Battle of Neuve-Chappelle in France in 1915 were based entirely on aerial reconnaissance photographs. The Germans and the British photographed the entire front at least twice a day. After the war, England estimated that its flyers took one-half million photographs during the four years of the war, and Germany calculated that if you laid all its aerial photographs side by side, they would cover an area six times the size of Germany. The quality of cameras had improved so much by the end of the war that photographs taken at 15,000 feet (4,572 meters) could be blown up to show footprints in the mud.


Reconnaissance pilots had proved their usefulness to the military. Unfortunately, both sides knew that if they were receiving valuable information from their pilots, the other side must be doing the same. Pilots realized that the enemy they had flown past and given friendly waves to was also close enough to shoot with a service pistol. Ground mechanics began mounting machine guns and soon, the Germans debuted the Fokker Eindecker as a separate type of airplane--fast, light, and well armed with a trained pilot--to be devoted solely to destroying reconnaissance planes. Suddenly, the slow, awkward two-seaters, already weighed down with the heavy wireless equipment, became easy targets for enemy fighter pilots. Escort fighter planes were then sent to protect their own reconnaissance planes.


Even with threats from anti-aircraft guns on the ground and the fighter planes in the air, the reconnaissance work continued. In addition to observing the enemy’s troops, ground forces found other uses for airplanes. Artillery units were unable to see if they were hitting their targets, so airplanes hovering over the targets could send signals to help the units adjust their aim. Airplanes also served on contact patrols, communicating with infantry units that had become cut off from their Command. Planes would warn other units of the lost unit’s location so it wouldn’t be misidentified and shot at by its own forces.


Reconnaissance was not the most exciting duty for a pilot in the war. The airplanes they flew in, such as Caudrons, Albatros B.II, Slamson 2A2s, and the American De Havilland DH-4, were not the fastest or sleekest of the fleet. But in conjunction with other aerial observation systems--balloons, dirigibles, man-flying kites, and the fesselschraubenfliger (an early helicopter)--reconnaissance airplanes saw enemy movement long before it could be seen from the ground. And out of reconnaissance activities, all other military uses for aircraft emerged. The reconnaissance pilots were the first to fire at enemy airplanes and they were the first to drop grenades on troops below. The names of the reconnaissance pilots are not as well remembered as the names of the aces, but it was due to their activities that aviation became a part of modern war.


--Pamela Feltus



Boyne, Walter J. The Smithsonian Book of Flight. New York: Wing Books, 1987.

Kennett, Lee. The First Air War: 1914-1918. New York: Free Press, 1991.

Lawson, Eric and Jane. The First Air Campaign, August 1914- November 1918. Pennsylvania: Combined Books, 1996.

Morrow, Jr., John H. The Great War in the Air: Military Aviation from 1909-1921. Washington, D.C.: Smithsonian University Press, 1993.

Munson, Kenneth. Bombers, Patrol and Reconnaissance Aircraft, 1914-19. New York: Macmillan, 1968.

Watkins, Nicholas C. The Western Front From the Air. New York: Sutton Publishing, 1999.

League of World War One Aviation Historians: http://www.overthefront.com


Educational Organization

Standard Designation  (where applicable)

Content of Standard

National Council for Geographic Education

Standard 1

How to use maps and other geographic representations, tools, and technologies to process information.

National Council for Geographic Education

Standard 13

How forces of cooperation and conflict among people influence the division and control of the Earth’s surface.

International Technology Education Association

Standard 4

Students will develop an understanding of the cultural, social, economic, and political effects of technology.

International Technology Education Association

Standard 10

Students will develop an understanding of the role of trouble shooting, research and development, innovation, and experimentation in problem solving.