Robert Silk
This year marks 100 years since the crop-dusting company that would evolve into Delta Air Lines took its first flight.
As U.S. airlines begin hitting their centennial -- American follows next year and United turns 100 in 2031 -- it's fun to consider what the flight experience was like in those early years.
It's also worth thinking about what dramatic transformations lie in airlines' future.
Aviation historian Shea Oakley spoke with me recently about the Douglas DC-3, a revolutionary aircraft for its time, which entered service in 1936. With its 21 seats, the DC-3 was the first aircraft with which airlines could make a profit through passenger service alone, without necessarily relying on mail delivery.
But to fly on the DC-3, or any aircraft, during the first decades of the airline industry meant subjecting oneself to plenty of discomfort and a fair bit of danger.
The first pressurized aircraft didn't appear until 1940, meaning flights had to stay low, where they are especially subject to turbulence.
Seats, Oakley said, were often metal or wicker.
Weather frequently grounded planes. And it was so noisy in the cabin that passengers would sometimes communicate by passing notes.
Further, crashes were much more common. Between 1930 and 1937, U.S. airlines with loads of at least three people had 45 accidents, according to PlaneCrashInfo.com.
"It was just a miserable experience," Oakley said. "It was adventurous but miserable."
Modern technology has solved many of those early pitfalls. Sure, economy flying isn't very comfortable, but that's a relative concern. Crash rates are way down. There's no need to scream to be heard. And planes fly high above the clouds, with satellite tracking and communications capabilities to, in many cases, steer clear of turbulence.
But back in the 1920s, human-induced climate change wasn't a known phenomenon, and airlines needn't worry about carbon emissions.
Over the next generations, solving the emissions problem will be the aviation industry's biggest challenge.
The global airline industry has committed to achieve net-zero emissions by 2050. And while it's unclear if that lofty target is attainable, the pressure on airlines to fly cleaner isn't likely to substantially abate in the coming decades.
For now, flying the most modern planes with the densest seat configurations is the most effective way for airlines to reduce their per-passenger carbon footprint, as a recent analysis by industry data provider Cirium illustrated. But over the next several decades, a dramatic ramp-up in the production of sustainable aviation fuel, coupled further down the line with the realization of new flying technologies, are the path toward true transformation.
Already, numerous companies are at work on electric flying solutions geared toward being viable for commercial airlines, at least on short routes, as battery technology improves.
Zero-emissions, hydrogen-powered aircraft capable of covering long distances are also part of flying's future, even though Airbus has stepped back from its earlier goal of introducing a hydrogen-powered narrowbody by 2035.
And new aircraft shapes, especially the blended wing design under development by JetZero and other aviation startups, have the potential to reduce emissions by 50% through aerodynamic improvements.
Flying today is nothing like it was when Delta got into the passenger air business. But where safety, range and comfort were the big frontiers for the industry during its early years, efficiency is now the north star.