This month marked 100 years since the first scheduled air service. What have been the most important steps to make air travel the massive industry it is today?

On 1 January 1914, PE Fansler took one small step for transport scheduling and one giant leap for mankind. In an effort to drastically reduce the day-and-a-half it took to travel the 23-mile journey between the Florida cities of St Petersburg and Tampa, Fansler brought in new flying boats built by American aviation pioneer Thomas Benoist.

Former St Petersburg mayor Abram C Pheil had stumped up $400 ($9,300 in today’s money) for the honour of being the first passenger. The modest seaplane, capable of flying at a top speed of little more than 60mph, completed the journey in just over 20 minutes.

It’s from this humble beginning that a new age of travel began. That single passenger a century ago sparked the creation of an industry that has resulted in an estimated eight million people flying every day, according to the International Air Transport Association. Total annual passenger numbers passed the three billion mark for the first time ever in 2013. So what were the spurs that took commercial aviation from flights of fancy to a genuine industry?

Commercial passenger aviation didn’t take off immediately – those first pioneering designs, like the four-engined, World War I-era Ilya Muromets, made only faltering steps at shrinking the planet.

“The advent of fast, all-metal and comfortable streamlined monoplanes – notably the Douglas DC-3 in 1935 – changed everything, encouraging Americans to switch from long-distance trains to flying across the States,” says aviation expert Jonathan Glancey. “They had pressurised passenger cabins, allowing flight high above clouds and most turbulence.”

Commercial aviation took a back seat during World War II – a period which saw aviation design go from the last days of the biplane to the jet fighter in just six years – but enjoyed its most dramatic growth in the decade after. Just like rock ‘n’ roll, the airline industry we see today has its roots in the 1950s. The year 1957 was the tipping point, says aviation writer Bruce Hales-Dutton. "This was when the number of passengers travelling by air within the US exceeded the number going by rail for the first time.”

But then came the jet age, and with it a shift in power. Britain ruled the roost with its de Havilland Comet, which became the first jet airliner to cross the Atlantic in October 1958. But “the Jet Set arrived with the much larger, more economical and all-conquering Boeing 707 just three-weeks later,” says Glancey. American industry, in the ascendancy, was able to wrestle the crown from Britain, and the Boeing achieved runaway success.

“It wasn't until the arrival of the wide-bodied airliners in the 1970s, like the Boeing 747, which provided the spur to real growth as the airlines were able to offer more economical travel,” says Hales-Dutton. Bigger planes meant more seats, and more seats meant tickets could be cheaper. Journeys once the preserve of the rich were suddenly affordable.

In terms of pioneering tech, aviation writer Angus Batey cites Airbus’s breakthrough A320 because it was the first digital fly-by-wire airliner. “[It] revolutionised the role of the pilot and the safe operation of civilian aircraft,” he says, “in ways that are still causing reverberations throughout the industry today and which, indeed, may not yet be fully appreciated or understood.”

There are other ways, Batey says, that we may be returning to the joy of flight that Abram C Pheil might have seen from the passenger seat of a flying boat 100 years ago – such as the layout on Boeing’s new 787 Dreamliner. “Making the windows bigger, making the cabin a bit more spacious, with ambient lighting and even by having the basic colour scheme including a lot of the colours we associate with skies (blues and whites), they're doing their best to get us to experience flight, rather than to just go from A to B.”

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