Airplanes, oxygen and the media

I'd like to note that those are two different adjustments. The claim is that pilots adjust the mix of fresh and recirculated air. The author is talking about adjusting the incoming flow volume of new air. Airplanes don't have "recirculate" the way a car does for max A/C, and so to talk about the mixture of fresh/recirc air is meaningless.

All those little air valves above the seats in a plane are letting in only conditioned air newly drawn from the atmosphere through the engines, with no recirculated air mixed in. The pilot can change the total amount of new air coming in, but that's not the same as somehow making only 20% of that incoming flow fresh air. The only place the air already in the plane is going is straight overboard, through valves run by the pressure controller.

(I'd also point out that the fuel savings from a low-flow setting will be minimal, because modern large high-bypass turbofan engines can bleed a LOT of air without much of a performance cost. The bigger the airplane and its engines, the smaller the savings.)

Particularly since one of said ways is done to to save fuel when the plane's not fully loaded.

Oops! Thanks and noted :)