# Pressure in Airplane Cabin

#### ChAoTiCpInOy

##### Diamond Member
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
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
I'm pretty sure they increase the pressure at ground level so that when you are cruising it's 'normal'.

#### ISAslot

##### Platinum Member
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."

#### SonnyDaze

##### Diamond Member
Increase in air pressure.

#### ChAoTiCpInOy

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

#### CrimsonWolf

##### Senior member
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
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
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
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?

#### rudder

##### Lifer
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
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
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
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
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....

#### LS21

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

#### ChAoTiCpInOy

##### Diamond Member
Grandfather can't handle the changes in pressure for a flight from San Francisco to Manila.

#### OCGuy

##### Lifer
Yea I was afraid to fly after my Pneumothorax