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verticallimit
17th Jul 2022, 13:29
Can companies order a cheep or a better and more expensive air decompression system in commercial aircraft, for example, Airbus / Boeing
I ask because sometimes I experience more pressure for the ears in decent.
The list is long of extra purchases when buying new aircraft, there are many options, but is there a grade of the pressurization system.

Or is "hard" decompression controlled by company rules, pilot related or even manufacture related.

Thanks.

MechEngr
17th Jul 2022, 18:36
On descent the aircraft interior will start re-compression. If it doesn't then the fuselage can be crushed by outside air pressure. Your eardrums feel the same pressure change and should equalize via the Eustachian tubes. Yawning, or pinching off the nose while slightly exhaling, as scuba divers do when they descend to higher pressure depths, can force air pressure to equalize.

The only technology answer is to build a far stronger fuselage so that the pressure at altitude is closer to the pressure on the ground. Increased pressure increases the stress on the fuselage which can lead to fatigue failures which are avoided by shortening the number of pressurization/depressurization cycles. It's been a concern since the initial designs for Comet aircraft led to crashes.

EXDAC
17th Jul 2022, 18:58
The list is long of extra purchases when buying new aircraft, there are many options, but is there a grade of the pressurization system.
Or is "hard" decompression controlled by company rules, pilot related or even manufacture related.

Not aware of any cabin pressure controller options in any modern aircraft. Control is typical fully automatic with no crew intervention required unless there is a failure. Older aircraft may require a manual setting of the landing altitude.

Cabin pressure will vary between ambient pressure at takeoff, reduce during climb, be stable in cruise, and increase on descent to equal the landing airport ambient pressure. Different aircraft types may have different cruise cabin altitudes (air pressures) for the same aircraft altitude.

Airmann
18th Jul 2022, 00:40
Try to fly in newer planes with carbon fiber fuselage. They generally are pressurized to a lower Altitude than regular aluminum aircraft as they can withstand higher delta Ps.

verticallimit
30th Jul 2022, 21:32
Thanks for your answers

DaveReidUK
31st Jul 2022, 06:35
Long gone are the days when the F/As used to hand out boiled sweets. :O

Zar_1
14th Apr 2023, 12:05
Try to fly in more modern airliners as they do have a more comfortable cabin pressure (and sometimes) humidity.

AFAIK, all aircraft use an in-house pressurization system. The ear popping you feel is not due to the low pressure, but due to the gradual change from HIGH -> LOW -> HIGH pressure during climb and descent.