It is ironic that much of the development work involved in producing today's efficient and safe jet airliners came about partly because of war, but it is a fact that much of the major development work for aircraft was as a result of military requirements. The first use of "air-power" in a military conflict was as far back as 1794 when the French army used hot-air balloons to spy on the positions of the Austrian troops at the Battle of Fleurus. They were used in the American Civil War as well.

Even the Wright Brothers spent much of their time trying to sell their airplane concept to the military, of the USA and France in particular – the early development of aircraft was never linked to the possibility of carrying passengers. The first powered military aircraft was a Wright Flyer, Model A, used by the US Army Signal Corps (there was no Air Force as such at the time) in 1909. It was capable of carrying two crew, had a maximum speed of 42 mph and a range of about 125 miles. The Wright Brothers were paid $30,000 for it – about $750,000 in today's money. Yet the Americans were very slow in taking up this new technology and it fell to Europeans to press ahead with developments, particularly the French and Germans. By 1911 the Italians were dropping bombs from aircraft in the Italo-Turkish War.

In 1909 the French had formed their Service Aéronautique, generally believed to be the first dedicated "air force" in the world. It later became the Armée de l'Air. The Germans formed their Fliegertruppen des Deutschen Kaiserreiches (Imperial German Army Air Service) in 1910 – it had become the Luftstreikrafte by 1916 – it did not become the Luftwaffe until 1935. In 1910 the British Army set up the Air Battalion of the Royal Engineers. Would-be pilots had to already hold a Royal Aero Club certificate and then had to pay £75 for their training. By 1912 the Royal Flying Corps and the Royal Naval Air Service had been established. The Royal Air Force was only formed in April 1918.

The early part of the First World War saw planes used for reconnaissance more than anything else (bombs were being dropped over England by the Germans using Zeppelin balloons rather than planes), though as the conflict wore on some were used to drop bombs or gas. They also got involved in "dog-fights". We can never forget the exploits of the "Red Baron" in his Fokker DR1 - painted red, of course.

But military planners generally were slow to see the benefits of flight and at the start of World War I France had only 140 aircraft, Britain less than that. Four years later France had built 68,000 planes, though 53,000 of them had been lost in action, either shot down by the Germans or crashed on landing or take-off. Great Britain produced 58,000 (losing 36,000); and Germany produced 48,000 (losing 27,000).

Manfred Albrecht Freiherr von Richthofen was born in 1892 into an aristocratic family, and excelled at school in sports including hunting and gymnastics. When the war began he became a reconnaissance officer but soon bored of this and applied to train as a pilot. By 1916 he had qualified and began his spectacular career. In September of that year he was credited with his first "kill" in air-to-air combat, over France. The early planes he flew were Albatros D-II and D-III but he later changed to the Fokker DR 1. In all he was credited with 80 "kills" and awarded the Blue Max, Germany's highest military honour of the time. Yet he met his end before the war finished, being killed by a singe bullet which penetrated his chest whilst he was involved in a dogfight over the Somme battlefields. The bullet was probably fired from the ground. Yet he still managed to land his plane but died before he could be pulled from it. His skill and daring had earned him the respect of the Allied forces and he was given a full military funeral, being buried near Amiens. His remains were moved later, first by the French, then, after the war, to Berlin and, later, to his final resting place, the family tomb at Wiesbaden.

By mid 1915 the Germans had gained air superiority, primarily with their Fokker built aircraft and, a little later, the Albatros series. Air superiority fluctuated to and fro between the two sides. A new aircraft development on one side gave them a temporary advantage, as happened with the so-called "Fokker Scourge" in April 1915 when the Germans put their Fokker E1 planes in the skies – this was the first plane with synchronised machine-guns firing through the propellor arc and gave them a huge advantage over the poorly-armed Allied planes. The pendulum swung back in the Allies favour in 1916 but in April 1917 the Germans again had the upper hand with their Albatros models. Later that year the Sopwith Camel, the SPAD S-XIII and the RE8 planes came into action. At the same time newer German models (Pfalz D-III and the Fokker DR-i) were plagued with technical and supply problems. By then the tide had turned and the ground war was running in favour of the Allied forces.

At the end of the war there were many planes sitting around with nothing to do – and plenty of pilots too, who could not use their skills in a more peaceful manner. It was almost inevitable that this should have been the push needed for non-military aviation to make progress, which is exactly what happened. Civilian passenger air services began in several countries and in the USA a postal air service started, using ex-military pilots. Aviation also became a sport an there were many races organised, together with tests on long-distance flights, including coast-to-coast in the USA, transatlantic and California to Hawaii. In 1927 Charles Lindbergh became the first man to fly non-stop from New York to Paris, solo. He won a prize of $25,000 for doing so. Two Britons also flew from London to Australia in a Vickers Vimy biplane.

In 1923 air-ro-air refuelling was first pioneered. A year earlier, despite initial misgivings and opposition from the Navy, the United States commissioned its first aircraft-carrier in 1922. The British Navy first ordered an aircraft carrier in 1917 though it did not come into use until 1923; the Japanese brought a carrier into use the year before. Ships had been used as seaborne "airfields" for some planes during World War I, (a plane had even taken off from the deck of a US Navy vessel in 1910) but these were adapted cargo vessels. The slow take-off and landing speed of planes at the time, and thus their short "runway" requirements, made this possible but as larger planes began to appear it was more of a problem and the catapult was invented for assisted take-off.

Between the wars development of military aircraft continued though at the same time much of the technology gained from the war years was put to more peaceful use in the construction of passenger-carrying airliners. The era is often regarded as the highlight in glamour travel. Certainly the passengers were well looked after. On the military side, new innovations continued to come along, radar amongst the most important. Early patents on radar had been filed as far back as 1904, but during the First World War scientists on both sides worked feverishly trying to perfect the idea. It fell to the British to first use radar in warfare, when it came into use in 1940.

At the close of the 1920s most planes were still biplanes but the 1930s saw the development of monoplanes. They also became larger and had more powerful engines and metal was used more and more in construction, replacing the wood used previously. In the 1930s Britain developed the Tiger Moth (a de Havilland plane) and the Hawker Fury as well as the Spitfire (1938). Junkers, Heinkel and Messerscmitt developed faster planes for the Germans, and the Unites States started getting its act together to build planes like the B-17 Flying Fortress, a heavy bomber. Germany was able to test its new planes in the Spanish civil War, assisting its Condor Legion, and dive bombing of targets began, especially with the Henschel and Stuka bombers first flown in 1933 and 1936 respectively. These planes had air-brakes on the wings to help control the plane in a steep dive.

For details of the Second World War planes, and more recent developments, go to the page marked "Second World War Planes".