Questions tagged [cabin-pressure]
Airplane cabins are pressurized so that the air inside remains breathable at high altitudes.
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Do aircraft depressurise when taking off from a high elevation airport? [duplicate]
A jet aircraft generally maintains a cabin pressure of 7000-8000 ft during cruise. If the aircraft departs from a high elevation airfield, such as Quito (approx. 10,000ft), will the aircraft ...
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In an F-16, at what altitude is supplemental oxygen considered essential life support?
Combat aircraft like the F-16 employs hypobaric pressurisation with supplemental oxygen from a regulator.
However, at what point does the manual call for the pilot to start using the regulator, what ...
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How was the Douglas DC-6 pressurized?
It's my understanding that modern airliners are pressurized using bleed air from the compressor stage. But how did piston-engined aircraft like the DC-6 get pressurized? I couldn't find any answers ...
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Is there good information available on maximum operating altitudes whilst maintaining a sea level cabin?
I am in the process of reviewing the aircraft we regularly commission for air ambulance transfers. Although the majority of transfers are undertaken with a standard cabin altitude ( 4 - 8,000 ft) some ...
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Why is a dedicated compressor more efficient than using bleed air to pressurize the cabin?
Bleed air is air "stolen" from the compressor of the jet engine and has traditionally been used to pressurize the cabin. The alternative is to use a separate compressor just to provide cabin ...
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Is the Diamond DA62 pressurized?
In a recent conversation about the Diamond DA62 I was speaking with someone who thought the aircraft was pressurized. I was shocked considering the door design. Shocked to the point of disbelief. A ...
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How to escape from a pressurized airplane?
Saudia Flight 163 was an airplane where all passengers and crew onboard died following a cargo fire. The plane managed to land safely, and the passengers had moved to the front of the cabin. However, ...
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Is the cabin pressure "worse" at the back of the cabin than in front?
My mother has a bad hearing problem and wears 2 hearing aids. She tells me the air pressure is worse for her in the back of the plane than the front. I would like to know if this is true - is there a ...
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How is the 737 NG/MAX able to operate at a pressure differential greater than that at which the cabin-pressure relief valve operates?
So I was reading about the 737's cabin-pressurization system, and then I came across these two bits of information:
Limitations
Max differential pressure:
Series
Max Diff
1/200's [sic]
7.5psi
...
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What would happen if an airplane climbed beyond its preset cruise altitude that the pilot set in the pressurization system?
What would happen? Would the cabin pressure increase too much and cause damage?
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Why do paratroopers not get sucked out of their aircraft when the bay door opens?
A few instances of injury/death were reported when passengers/pilots got partially sucked out of the airplane due to cabin depressurisation in a commercial aircraft.
Paratroopers, on the other hand, ...
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How exactly does the cabin pressure of an airliner change during ascent and descent?
At cruise altitude, airliners' cabin altitudes are usually at 6000-8000 ft, but how and when does it get there respectively how does it behave from ground until cruise altitude?
Is the cabin ...
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How can an aircraft door be modified to open in flight at cruising altitudes?
Just do a Google search for opening an airliner door in midair will spring up a dozen sites of why this is nearly impossible, if not possible.
And the difference between the inside of the plane and ...
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What would be the lowest possible cabin altitude (respectively, highest possible pressure on board) of an airliner in 1155 Pa exterior pressure? [closed]
How well does an airliner's pressurization work at extremely high altitudes (extremely low atmospheric pressure)? Does the system provide an absolute pressure differential, or is the differential a ...
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Did Helios Flight 522 take off with its pressurisation mode selector in manual? [closed]
I'm currently doing a write up on the Helios Flight 522 disaster. Full disclosure, this is a journalistic piece, and I'm not an aviation expert.
I'm many hours in at this point and most of it so far ...
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Can airliners take off, cruise and land while unpressurized?
I'm wondering if the pressurization of the cabin has a part to play in the structural integrity of the fuselage, the same way an unopened soda bottle is stiffer compared to one that's open.
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How did the unpressurized Cessna Grand Caravan fly at 43,000 ft? [closed]
Recently I've seen a Cessna 208 Grand Caravan flying as high as 43,000 ft MSL on flightradar24. Perhaps it's still in the air if you look over eastern Canada (the Grand Caravan has a unique shape from ...
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How is airliner pressurization being coped with at high altitude airports? [duplicate]
Cabin altitude in a passenger airliner must not become more than 8,000 ft, but what if an airliner flies to or from an airport at a higher elevation, such as Quito and La Paz? How is onboard pressure ...
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With supplemental oxygen, what altitude can a pilot safely operate at?
Will there be operating limitations regarding ascent or descent speed to avoid decompression sickness?
What altitude will require a pressure suit?
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Who make the fuel system, cabin pressurization system, and firefighting system?
Who makes the fuel, cabin pressurization, and engine firefighting system for an aircraft with engines on, or in, the wings? Fuel tanks and fuel pipes, pressurized air pipes and heat exchanger, and ...
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How would tiltwing aircraft pressurize their cabins?
For fix-wing aircraft, the pressurized air can travel from the engine through the wing and into the cabin. However, a tilt-wing aircraft, such as the CL-84 Dynavert (shown below), will have its wings &...
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How are cabin pressure and oxygen level maintained inside the airplane? [duplicate]
How are cabin pressure and oxygen level maintained inside the airplane?
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Is it possible for a pressure loss in the cockpit to not extend to the cabin?
I have done research into the question of pressure differences between the cabin and cockpit and the theoretical answer I receive the most is that the pressure difference would equalize almost ...
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What happens if the crew do not set a FLT ALT in the cabin pressurization panel and leave it at zero but AUTO is still selected?
On the 737NG, will the cabin maintain a lower altitude than the plane or will cabin altitude equal aircraft altitude?
Will there be ANY cabin pressurization or none at all?
When will the HORN sound?
I ...
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Was there ever a supersonic flight in a non-pressurized plane, and what is/would it be like for the pilot?
If you went supersonic in a plane that has no pressurized cockpit, would you be completely deaf (because of flying faster-than-sound)? Would it be dangerous to the pilot even if he/she was in an ...
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How often is the cabin air replaced in A320?
One of the A320 pilots told me that there is an icao rule that air should be replaced every 90 seconds?
Is this true ? can someone give me a supporting article for the same
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How does outflow valve work?
As we know that outflow valve normally closes during climb and cabin altitude also increase but why does outflow valve open if we have selected manual pressurisation and increasing cabin altitude !
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Does ELMS inhibit cabin pressure alarms on the 777, and would the MEC Override Vent be stuck open following an electrical failure?
I found this article rather interesting, but like most things on the internet, they can be wrong. I couldn't think of a better site to address this question. This user says:
when ELMS takes over ...
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How can I communicate an emergency de-pressurization descent to the cabin as a passenger?
Hypothetical scenario. I'm on a commercial airliner (A320) as a passenger, sitting by the wings. We are cruising at 32,000. The oxygen masks suddenly drop down and the nose pitches down heavily, ...
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Why does the 737-300 outflow valve indicator give different readings?
The 737-300 outflow valve opens and closes in manual mode under AC or DC side. While in DC, the indicator is accurate, but when it's in AC mode it reads open when closed.
Does the outflow valve have ...
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Can Airbus A320 doors be opened mid-flight?
Today I learned how airliner doors are typically an outward facing plug and cabin pressure would make them nearly impossible to open mid-flight.
It's easy enough to see that for the shape of Boeing ...
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Why does a decompression occur when a hole appears on the fuselage of an aircraft? [closed]
I've never understood the mechanics behind explosive decompression and what is has to do with the difference of pressure.
I know the pressure in the cabin is set to a certain point, but don't ...
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How are turboprops and other propeller planes pressurized?
I know how most turbofan jets are pressurized:
But it can't be the same with turboprops, as I don't understand how propellers can take in the air. Yet, planes like Q400s can fly above 8000', all the ...
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What is the Function of Pressurization Light on Exit Doors for Commercial Airliners?
I am well aware that the average human is unable to open plug doors in flight due to pressurization of the cabin. I've noticed, however, a "cabin pressure" warning light in the window of exit doors, ...
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What is the physical experience of passengers in the cabin during an Emergency Descent?
I am not a pilot so please forgive any misuse of aviation terminology; I'm merely a person who is working hard to overcome a sudden and intense fear of flying.
While working through a course to ...
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Why don’t airports use jetways as an airlock to avoid having to repressurize the plane for every flight?
Seems like it could save money perhaps. Has this been considered in the past?
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How does a DC-10 flight engineer manually raise the cabin altitude?
Reading into Federal Express Flight 1406 and I noticed when the flight engineer said he was raising the cabin altitude “manually” I assume this has something to do with cutting off the oxygen, but how ...
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If you depressurize an aircraft at FL340, will the temperature inside fall to match the temperature outside?
Assuming you’d have an oxygen mask on before hand, and you depressurized the aircraft at FL340, would the inside and outside temperatures quickly become the same?
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Is the F-16 cockpit pressurized?
Is the F-16's cockpit pressurized? If so, why does the pilot receive oxygen from the mask (please state the correct terminology for this)? Is it due to redundancy in case cabin pressurization fails?
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What is pressurization influence (if any) on maximum G load an airliner can withstand?
Reading here about skin thickness of airliners I was wondering if, considering some pressurized airliner at cruise altitude, there are differences in maximum operational acceleration loading the ...
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Can pressurized aircraft be flown without pressurizing
Are there any pressurized aircraft models which can also be flown without pressurizing the cabin?
For example, if there were a short ferry flight, or a flight where the aircraft never got high enough ...
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How does cabin pressure vary with respect to ambient pressure during descent?
I came across this statement in a book -
"During a descent, the cabin pressure in a pressurized aircraft usually climbs at as lesser rate than ambient pressure".
Could someone explain this statement ...
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Why was the 307’s pressurisation system removed when it was modified into the C-75, despite the fuel-burn advantage of higher-altitude flight?
The Boeing 307, an airliner derivative of the B-17 heavy bomber, was the first pressurised airliner to enter series production and go into service (hence its bulbous, altogether un-B-17-like fuselage, ...
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Why would short-haul flights be pressurised at a higher cabin pressure?
In the article here : https://abcnews.go.com/Health/Healthday/story?id=4507808&page=1 it is claimed that
Short-haul flights are usually pressurized at 5,000 to 6,000 feet while long-haul ...
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How Cabin Pressures Are Selected?
The pilot puts the cruise altitude to the FMC and the plane auto adjusts the cabin pressure. I know that but I once heard the cabin pressure is set to three thousand feet.
Is it true? Why is the ...
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Why aren't aircraft cabins pressurized to sea level pressure?
From an article on WHO's website:
Although aircraft cabins are pressurized, cabin air pressure at cruising altitude is lower than air pressure at sea level. At typical cruising altitudes in the ...
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Is it possible for crew oxygen to exacerbate a flight deck fire?
Crew oxygen is, as I understand it, a very high percentage of purity.
Oxygen-enriched air acts as an accelerant to a fire, causing things to ignite which wouldn't in ordinary air, and making fire ...
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Why is the alternate static pressure lower than the standard static vent pressure regardless of the venturi effect on both?
I understand that the higher relative airspeed around the body of an aircraft in comparison to the air within the cabin causes the cabin to experience a lower pressure.
However, I was just thinking ...
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Why don’t double-bubble fuselages cause severe fatigue problems?
In response to my previous two questions about fatigue issues, or the lack thereof, generated by the cusps in double-bubble-fuselaged aircraft (Stratocruiser, DC-9-80), I received a number of answers ...
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How much air does a 777-300ER's pressure cabin hold?
I've been wondering how much air a 777-300ER's pressurised cabin holds, but, while most of its specifications are fairly easy to find, the amount of air it contains is not.
Does anyone know what ...
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