The War in the air was initially limited to observation. Kite balloons were used to great effect in this role. They were suspended from lorries by steel cables and could be winched up and down depending on poor weather conditions or any sign of enemy attack. More accurate than any moving aircraft, these balloons could also be used as decoys to destroy enemy aircraft. For example, when the enemy approached all but one of the balloons would be winched down. Instead of observers, the basket of the remaining balloon was filled with high explosives.

'The hero who dived on the balloon would be welcomed by Archie, flame throwers, and the bursting balloon itself.'

Giant airships measuring 420 feet by 40 feet wide were used to great effect in reconnaissance flights over the North Sea and in bombing raids on Britain and France. These Zeppelins were made out of a frame of aluminium girders, filled with hydrogen gas bags and were powered by two motors.

However by 1916 anti-airship defences, such as searchlights and incendiary bullets, which set light to the hydrogen and brought the airships down in flames, had been successfully developed. The vulnerability of the Zeppelins to explosive shells, and their relatively slow speed brought about a decline in their use. Instead there was a rapid development of heavier-than-air machines such as the BE Biplane that was used to great effect as an observation tool until 1916, when its clumsy manoeuvrability proved useless for aerial combat.

To begin with aeroplanes were also mainly used for reconnaissance and observation as support for the infantry and artillery.

'Aerial combat developed because the enemy naturally wanted to stop such activities and the inevitable response was to fight back. This led to the production of a whole range of new and more sophisticated aeroplanes.'

Thinking Point: What technological advances changed the nature of fighting in the air?

Technological advances were made quickly and relentlessly as each country tried to outdo the other in the success of their aircraft. Advances such as timed machine-guns meant planes could be used in combat without the danger of the pilot shooting off his own propellers, and the development of precision bombers gradually made the aeroplane a more useful weapon of war.

For example, the British introduced the Sopwith Camel in 1916 to replace the BE Biplane. Sopwith Camels were equipped with a Vickers machine gun at the front of the plane and were easy to manoeuvre. Likewise, the Germans introduced the Gotha in the autumn of 1917. The Gotha GIII shown here was equipped with a dorsal gun that fired downwards beneath the tail of the plane.

These developments in aerial warfare saw the arrival of 'dogfights' over the Front between enemy fighter planes and with it the celebrated fighter pilots. In a war of muddy stalemate and relative inaction these 'Air Aces' brought an element of glamour. The successes of airmen such as Britain's Edward Mannock and Germany's Baron Von Richtofen (the Red Baron) were of great use to their country's propaganda effort in generating publicity.

In recognition of the increasing importance of war in the air Britain created the Royal Air Force in April 1918, which was to play a vital role in future conflicts such as the Second World War.