Pressure in Airplane Cabin

ChAoTiCpInOy

Diamond Member
Jun 24, 2006
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We all know that they equalize the pressure between the outside and inside at ground level so when the plane is at cruising altitude they are able to breathe normally. Why is it that even with this equalization of pressure your ears still pop when the plane ascends.
 

mundane

Diamond Member
Jun 7, 2002
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If I had to guess, I'd say they don't quite maintain the ground level pressure, but something marginally less than that.
 

Crusty

Lifer
Sep 30, 2001
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I'm pretty sure they increase the pressure at ground level so that when you are cruising it's 'normal'.
 

ISAslot

Platinum Member
Jan 22, 2001
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Originally posted by: ChAoTiCpInOy
We all know that they equalize the pressure between the outside and inside at ground level so when the plane is at cruising altitude they are able to breathe normally. Why is it that even with this equalization of pressure your ears still pop when the plane ascends.

Wikipedia:
"The pressure maintained within the cabin is referred to as the equivalent effective cabin altitude or more normally, the ?cabin altitude?. Cabin altitude is not normally maintained at ground level (0ft) pressure throughout the flight because doing so stresses the fuselage and uses more fuel. An aircraft planning to cruise at 40,000 ft (12,000 m) is programmed to rise gradually from take-off to around 8,000 ft (2,400 m) in cabin pressure altitude, and to then reduce gently to match the ambient air pressure of the destination. That destination may be significantly above sea level and this needs to be taken into account; for example, El Alto International Airport in La Paz, Bolivia is 4,061 metres (13,320 ft) above sea level."

 

ChAoTiCpInOy

Diamond Member
Jun 24, 2006
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How hard would it be to convince a pilot to use the pressure at ground level throughout the flight?
 

CrimsonWolf

Senior member
Oct 28, 2000
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Originally posted by: ChAoTiCpInOy
How hard would it be to convince a pilot to use the pressure at ground level throughout the flight?

Not going to happen. The bodies of aircraft are not designed to handle that pressure - it would cause to much stress. (And making the bodies stronger adds weight, all else held equal.)

Typical pressure is around 8,000ft equivalent. Boeing's new 787 Dreamliner uses a stronger composite body that can handle pressure of about 6,000ft.
 

randay

Lifer
May 30, 2006
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Originally posted by: ChAoTiCpInOy
How hard would it be to convince a pilot to use the pressure at ground level throughout the flight?

no need to convince him, just remove him with some box cutters and do it yourself?
 

D1gger

Diamond Member
Oct 3, 2004
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Originally posted by: ChAoTiCpInOy
How hard would it be to convince a pilot to use the pressure at ground level throughout the flight?

Why do you care?
 

buck

Lifer
Dec 11, 2000
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Originally posted by: randay
Originally posted by: ChAoTiCpInOy
How hard would it be to convince a pilot to use the pressure at ground level throughout the flight?

no need to convince him, just remove him with some box cutters and do it yourself?

:confused:
 

rudder

Lifer
Nov 9, 2000
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Originally posted by: ChAoTiCpInOy
How hard would it be to convince a pilot to use the pressure at ground level throughout the flight?

but then you would have to buy more alcohol because it would not affect you as much. Really though its about 7-8,000 foot pressure atltidude... hardly noticeable.

Your ears pop because the pressure is slowly brought down to the airport elevation. Otherwise when the flight attendent opens the door... everyone will scream.
 

spidey07

No Lifer
Aug 4, 2000
65,469
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Originally posted by: ChAoTiCpInOy
How hard would it be to convince a pilot to use the pressure at ground level throughout the flight?

That would damage the plane and you would crash. You do not want that.
 

Linflas

Lifer
Jan 30, 2001
15,395
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P-3 Orions have a cannister vacuum system that works off the difference between cabin pressure and outside air pressure. It has a hose that plugs into an opening in the bulkhead and runs to a canister with a filter and long hose with a floor attachment. They use it to clean out the aircraft flying back from missions.
 

MattCo

Platinum Member
Jan 29, 2001
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Originally posted by: spidey07
Originally posted by: ChAoTiCpInOy
How hard would it be to convince a pilot to use the pressure at ground level throughout the flight?

That would damage the plane and you would crash. You do not want that.

The aircraft's captain may elect to maintain cabin altitude at sea level on request to address compelling pressure-sensitive medical needs of a particular passenger, but at an operational cost to the airline arising from fuselage fatigue.

From same article mentioned above:
http://en.wikipedia.org/wiki/Pressurized_cabin
(For GoSharks)
 

GoSharks

Diamond Member
Nov 29, 1999
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Originally posted by: MattCo
The aircraft's captain may elect to maintain cabin altitude at sea level on request to address compelling pressure-sensitive medical needs of a particular passenger, but at an operational cost to the airline arising from fuselage fatigue.
AFAIK, maintaining at sea level while at cruising altitude is physically impossible on modern passenger planes.

BTW, did you enter that into Wikipedia? Otherwise you should quote or at least cite....

http://www.airliners.net/aviat...00639/?threadid=200639
http://www.airliners.net/aviat...29076/?threadid=129076
 

LS21

Banned
Nov 27, 2007
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the pressure is highly variable within the cabin of the airplane. ive monitored my altimeter watch before...,