It's been 20 years since smoking was completely banned on all US flights. Here's how smoking on planes went from normal to banned.

Smoking and airplanes once went hand in hand but the practice is now largely banned the world over.
US government regulations on smoking on airplanes first began in the 1970s and culminated in smoking being banned on all flights touching US territory.
China most recently banned smoking on its planes in 2016 and later eliminated an exception that allowed pilots to smoke in the cockpit.
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"Smoking or non-smoking?" That question used to be asked of travelers when booking a seat on an airplane in the US from the 1970s until 2000 when smoking on airplanes was fully banned by the federal government.

In the early days of air travel, smoking on an aircraft was as common as ordering a drink, especially in the onboard lounges of grand aircraft like the Boeing 747.

As the science on smoking became more clear and society moved away from the practice, aircraft became one of the main targets for prohibition. Slowly but surely, airlines and governments took action and incrementally restricted what was once a freely acceptable activity on an airplane.

With passengers around the world becoming increasingly averse to smoke-filled cabins, however, the option to smoke on an airplane became scarcer and airlines started to go smoke-free despite alienating a segment of their customer base.

It wasn't until 2000 that the US banned smoking on all flights to, from, or within the US. Now, it's nearly impossible to travel on an aircraft that allows smoking.

Take a look a back at the history of smoking on airplanes and how it took 23 years to eliminate the practice from US skies.

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