The series begins before the First World War when military commanders struggled to understand what uses aviation might have. The Wright Brothers had been the first to fly a powered aircraft in controlled flight in 1903, but even by 1914 aircraft were still fragile and underpowered. But the WWI saw the aeroplane develop into a formidable weapon capable of carrying bombs for thousands of miles.

The 1920s and 30s were uncertain times for the RAF as well as all other armed services. With peace came cuts in spending on new aircraft development. The RAF found a useful role 'policing the Empire' - going to far-flung places that would have tied up land forces for months to reach and garrison. But, with the Second World War looming, money began to flow into aircraft design and production.

By the end of the war the RAF had aircraft that could escort bombers to targets deep inside Germany and back. With the Gloster Meteor, the RAF had also entered the 'Jet Age'. Aircraft like the Hawker Hunter and F-86 Sabre took the RAF supersonic. This was the era of QRA - Quick Reaction Alert - when aircraft sat at the end of runways ready to launch in minutes to intercept intruders.

By the end of the First World War the RAF had bombers that could fly to Berlin and back. For the first time in a thousand years British civilians found themselves under direct attack - by Zeppelin airships and Gotha bombers. The experience left an indelible impression on the public psyche, which was only exacerbated during the Blitz that began in the winter of 1940.

The RAF's maritime role is often overlooked. Between the wars the RAF operated elegant flying boats to patrol the far flung corners of the Empire. During the Second World War, air sea rescue of downed pilots and air crews was a vital role. Large flying boats like the Short Sunderland and PBY Catalina flew long missions far out over the oceans, looking for enemy submarines.

After the war, RAF transports helped keep Berliners alive during the Soviet blockade of the city in 1948/49. As well as flying round-the-clock operations into the airport, Sunderland flying boats delivered supplies by landing on Lake Havel near the city. During the 1960s the RAF augmented its fixed wing aircraft with helicopters like the Chinook.