Questions tagged [cabin-pressure]
Airplane cabins are pressurized so that the air inside remains breathable at high altitudes.
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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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1answer
137 views
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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5answers
497 views
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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1answer
118 views
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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1answer
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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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1answer
116 views
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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Why is an airliner cabin pressurized to a pressure altitude below field elevation before takeoff and landing? [duplicate]
Why is an airliner cabin pressurized to a pressure altitude lower than field elevation before takeoff and before landing, as depicted in the graph accompanying this answer?
How does the cabin ...
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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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1answer
93 views
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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1answer
589 views
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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2answers
223 views
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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51 views
Cabin pressured for flights to/from high altitude airports [duplicate]
I was flighting from La Paz (El Alto airport, LPB) which it is located at an altitude of 4061 m (13 600 ft), which is above standard pressure of passenger flights.
How is the cabin pressure usually ...
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3answers
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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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1answer
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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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1answer
146 views
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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2answers
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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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1answer
986 views
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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1answer
400 views
Is the air in aircraft cabin toxic?
I just listened to the recent BBC podcast episode Aerotoxicity: the hidden dangers of flying and there were interesting claims there:
Cabin air in modern passenger aircrafts comes directly from ...
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2answers
119 views
Which are the advantages of low pressure levels during flight? (i.e during cruise flight in a commercial aircraft)
I understand that due to health and security reasons, there must be a minimum in the pressure inside the cabin (75 kPa). But in class I have been told that maintaining low pressure levels has ...
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1answer
567 views
Can the pilot stop airflow between cockpit and cabin?
During normal operation the entire fuselage is pressurized equally:
An aircraft fuselage does not contain separate compartments with different pressure values in each. The entire vessel is ...
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2answers
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Do pilots get more fresh air than passengers? [duplicate]
There is a famous air travel myth claiming that "pilots get more fresh air than passengers".
(source: The pure cure, p.375)
I would like experts to either dispel or confirm this myth, that ...
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2answers
715 views
Do pilots breathe the same air as passengers?
Do pilots breathe the same quality of air as passengers ?
(i.e. identical parameters: same O2, CO2 and O3 levels, same temperature, same humidity, etc.)
Do pilots breath the same air as passengers (...
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Why does the cabin air sometimes smell of kerosene? [duplicate]
Why does the cabin air sometimes smell of jet fuel, although bleed air is tapped before it comes in contact with fuel ? How is this possible?
I have smelled this a couple of times in my life (twice ...
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1answer
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Why and how can a fume event occur?
« A fume event occurs when bleed air used for cabin pressurization and
air conditioning in a pressurized aircraft is contaminated by fluids
such as engine oil, hydraulic fluid, anti-icing fluid, ...
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1answer
421 views
What's the cabin pressure of a Bombardier CRJ-900? [closed]
In terms of altitude (6000, 7000, 8000, etc), what is the cabin pressure in a CRJ-900?
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1answer
243 views
Why can't I ever get my right ear to pop on descent in a plane?
Whenever I'm flying, there's a period of descent where my right ear just refuses to pop. This has been bothering me for at least ten years.
There seems to be a long stage of descent where my ear is ...
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1answer
595 views
Are pressurized passenger aircraft usually completely airtight?
Various sources on the internet indicate that the passenger cabins on pressurised airplanes are not 100% airtight. I'm not talking about ventilation/pressure valves/cabin pressurisation system, but ...
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7answers
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Is it true that a soda can or a bag of chips will pop in a plane at high altitude? [closed]
I've heard some conspiracy theorists claim that if you were to bring a soda can or a bad of chips onto an airplane, they would pop?
Is this true? If so, why?
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2answers
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Is if safe/legal for an aircraft to return to cruising altitude after passenger oxygen masks have been deployed?
I was reading reports [1,2,3,4] about a recent Air China flight where one of the pilots was allegedly smoking and, in an effort to prevent the smoke circulating to the cabin, accidentally de-...
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Is the increased humidity on modern jets artificial?
Is the increased humidity on jets such as the 787 and A350 artificial? Or is it a direct result of a greater cabin pressure?
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1answer
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Was the safe landing of Southwest flight 1380 extraordinary or expected?
I've been reading with great interest and concern about the recent Southwest flight that resulted in the first fatality in that airline's history.
There's one question I haven't seen answered, though:...
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2answers
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How can I calculate the cabin pressure following a decompression?
What are the calculations to determine the level of cabin pressure at a given altitude once the cabin is punctured?
I was unable to determine the window size and the flow rate of the compression ...
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1answer
525 views
What are the layers of a pressurized fuselage (cross-section and construction)?
I've looked all over this site, and also Web searches - but I can't seem to find any discussion about, and the construction cross-section of, a commercial airliner's pressurized fuselage wall. Not ...
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3answers
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I have really intense ear pain during descent in commercial flights. Would it be better or worse if I was flying a small non-pressurized plane?
Usually — but not always — after descending in a commercial jet airliner, my ears really hurt for several days, accompanied by minor hearing loss.
Nonetheless, I am still in love with aviation. I am ...
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Is the air bleeded from the engine to maintain cabin pressure for airlines heated or cooled [duplicate]
Is the air bleeded from the engine to maintain cabin pressure for airlines heated or cooled. If heated, what device is used, if cooled, what device is used and in both cases how much energy does it ...
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What was the first commercial aircraft to have a 'built-in' oxygen system?
(Source) Boeing 307 of TWA, the 307 was the first pressurized passenger aircraft.
The 307 (c. 1938) flew as high as 23,300 ft, lower than the jets of nowadays, and did not have a built-in oxygen ...
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1answer
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Which was the first pressurized aircraft?
Which aircraft was the first one to fly pressurized?
High altitude breathing apparatus, 1918 (source)
I mean an aircraft which didn't require to don an oxygen mask above a certain altitude, ...
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1answer
624 views
Can the RAM AIR valve cause depressurization on the CRJ-900?
On the CRJ-900 AIR-CONDITIONING panel there is a RAM AIR switch light which opens a valve and allows air from the ram air scoop to enter the mixing manifold for distribution to both the flight deck ...
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What's the reason for “pre-pressurization” of the cabin prior to liftoff? [duplicate]
I'm reading a Citation M2's Pilot Training Manual, and it says:
...When the throttles are advanced for takeoff, the bleed air turns on
(if not already on for heating), and the pressurization ...
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1answer
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At which point does an airliner start to pressurize/depressurize the cabin?
Do airliners start changing cabin pressure at takeoff or after reaching a certain altitude? Also when do they start depressurizing the cabin ?
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How thick is the skin of an aircraft like the Airbus A350 or Boeing B777?
We can evaluate how thick walls are by looking at door or window frames, however that isn't representative of an aircraft fuselage, which appears to be very thin:
Airbus A350 XWB forward fuselage, ...
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1answer
396 views
If an aircraft decompresses at altitude will everyone start farting?
From what I understand about how gases and liquids work, if the environment loses pressure, then it causes dissolved gases to come out of solution. For example, if a diver ascends too quickly, ...
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2answers
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How does the outflow valve work on a cabin pressurization system?
When you fill up a cabin with warm air the pressure of the cabin will rise. An outflow valve controls the desired pressure. But with pressure rising doesn't the temperature rise because you're ...
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To what extent does pressurisation increase the rigidity of an airframe?
A vessel such as a balloon or the rubber air-cell of an inflatable boat will become more rigid when pressurised.
The same must happen to the fuselage of a pressurised aircraft - but to what extent?
...
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How much air is recirculated (vs. bleed air injected) in modern airliners cabin?
Air in the cabin of airliners is a mix between:
new air (engine bleed air or ram air in some aircraft) and
recycled air pumped out of the cabin, filtered and re-injected.
How much air is ...
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1answer
2k views
Why is the A320 pre pressurised before take-off?
I know this question has been asked, but I still haven't understood the answer. In the A320 the cabin gets pre pressurised before takeoff as we apply takeoff thrust. What I don't understand is what is ...
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Are there any pressurized piston-engine aircraft?
Are there any pressurized piston engine-powered aircraft? Or does pressurization require a turboprop or jet?
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How does bleed air maintain pressure for pressurization after being cooled?
I found on aerosavvy.com/aircraft-pressurization the paragraph below, which talks about bleed air on airliners:
Most modern airliners use bleed air from the compressor section of the engines to ...
