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Commercial jets are typically pressurized to the equivalent of 6,000 to 8,000 feet of elevation. But according to a study,[1] passengers begin feeling uncomfortable at about the 7,000 feet mark, right in the middle of that range:

we did find evidence that the level of hypoxemia manifested at 7000 to 8000 ft played an important role in the development of discomfort [...] we conclude that maintaining a cabin altitude of 6000 ft or lower (equivalent to a barometric pressure of 609 mm Hg or higher) on long-duration commercial flights will reduce the occurrence of discomfort among passengers.

According to the Wikipedia article on Cabin Pressurization,[2] the typical cabin altitude equivalent for new aircraft is "falling", which "significantly improves comfort levels", so perhaps making sure to fly on newer aircraft is part of the solution:

The designed operating cabin altitude for new aircraft is falling and this is expected to reduce any remaining physiological problems [...] The 787's internal cabin pressure is the equivalent of 6,000 feet (1,800 m) altitude resulting in a higher pressure than for the 8,000 feet (2,400 m) altitude of older conventional aircraft [...] such a level significantly improves comfort levels.

So, is there a reliable way to check that my upcoming commercial flights will be pressurized closer to 6,000 feet than 8,000 feet? And is there any way for me to avoid booking tickets on high-altitude-equivalent flights so that I can be sure to avoid airplane sickness during my travels?


[1] Effect of Aircraft-Cabin Altitude on Passenger Discomfort, DOI 10.1056/NEJMoa062770
[2] https://en.wikipedia.org/wiki/Cabin_pressurization

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  • It'll be a function of the aircraft type (B787, A320, etc), which should be disclosed at the time you book the ticket (though the airline can change it without notice). Probably there's somewhere that you can look up typical cabin altitude for various types. Of course it's entirely possible, and in many cases likely, that all available flights on your desired route use types with higher cabin altitude, in which case you are out of luck. Sep 10 at 23:08
  • @NateEldredge Thanks for the background. If that's true, then the question would basically boil down to: how would I go about looking up typical cabin altitude by aircraft? Taking the Airbus A330 as an example, I am not able to find this information with a Google search. Sep 10 at 23:15
  • Right, I agree. I couldn't immediately find it either. Sep 10 at 23:22
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    @NateEldredge You can look up the planned aircraft, you aren't guaranteed to fly that aircraft. Sep 11 at 2:27
  • I've always felt that dehydration was more of a problem than pressurization levels.
    – Peter M
    Sep 11 at 10:50
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The normal cabin pressure during flight is basically a function of the aircraft type. Maintaining a lower pressure in the cabin creates a higher pressure difference between the cabin and the air outside of the plane, which the aircraft needs to be able to sustain.

The vast majority of modern aircraft are pressurized to around 8,000 feet during normal flight, although there are 3 (or 4) exceptions.

The Airbus A380, Airbus A350, and Boeing 787 are all designed to be able to maintain a cabin pressure of 6,000 feet, and would normally be set to that for normal flight.

The 4th aircraft that (use to) support a cabin pressure of 6,000 feet was Concorde. Obviously not an option for flying today, but interesting given how long ago they started flying relative to the other models above.

So as far as knowing if an upcoming flight is going to be pressurized at 6,000 or 8,000 feet, simply look at the aircraft type flying it. If it's an A380, A350 or B787 then it'll almost certainly be 6,000 feet. If it's a Concorde, you need to have a word to your travel agent! If it's anything else, it'll be 8,000 feet.

(Note that cabin pressure isn't actually measured in 'feet', but it's a common way to refer to aircraft pressurization, referring to the normal atmospheric pressure at that elevation above sea level).

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  • Source: reuters.com/article/… mentions the the 787 and the A350. theluxurytravelexpert.com/2019/01/14/exciting-features-a380 mentions all three. Also, AFAIK you should mention the vast majority of commercial airliners -- business jets are often 6000 ft.
    – chx
    Sep 11 at 4:13
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    "Maintaining a lower pressure in the cabin creates a higher pressure difference between the cabin and the air outside" – This is wrong. Air pressure decreases with altitude, so the air pressure outside the plane is lower than in the cabin. Therefore, maintaining a lower pressure in the cabin decreases the pressure differential. That is the whole reason why airplanes lower the cabin pressure in the first place. Sep 11 at 8:02
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    @JörgWMittag Perhaps the term he was looking for was "pressure altitude" not simply pressure
    – Peter M
    Sep 11 at 11:23

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