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 difference in air pressure depending on where you sit in the plane?
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33$\begingroup$ She's right, she needs first class. $\endgroup$– 300D7309EF17Commented Mar 12, 2023 at 16:30
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4$\begingroup$ I remember running in an old bus long ago (~40 years ago and the bus was already quite old) where the acoustic resonance at some particular engine rpm gave me pain in the ears with some loud infrasound (I could feel the vibration). This happened only in particular place near the rear end of the bus. The effect was reproducible between different busses (they were the same make/model) and drivers. Bus drivers happened to like exactly this frequency / engine rpm for moderate uphills. This may or may not be related, modern airplanes should not have acoustic resonances this sharp. $\endgroup$– fraxinusCommented Mar 12, 2023 at 18:13
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2$\begingroup$ Is this question better suited to Travel stack exchange? Since it concerns a passenger flying commercial? (Aviation is more about laws, how planes work, history of flight, etc). $\endgroup$– Kevin KostlanCommented Mar 12, 2023 at 20:58
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6$\begingroup$ @KevinKostlan ASE is the appropriate place in the sense that the question and answers deal with the complex and demanding sensory environment of aircraft. $\endgroup$– Jpe61Commented Mar 13, 2023 at 8:27
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5$\begingroup$ The experience really is not about air pressure. We as humans have very few ways of actually experience air pressure. (Exceptions are things like congested vents from sinuses or inner ear, or gases in the stomach). What we mostly experience is changes in air pressure and they happen just about equally regardless of position in the cabin. But what does differ is sound, especially low frequency rumble from the engines. This, rapidly changing air pressure will be felt differently depending on position in cabin. Some aircrafts are worse (say SAAB SF340) than others. $\endgroup$– ghellquistCommented Mar 13, 2023 at 19:01
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5 Answers
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As stated in other answers, in steady flight there is no pressure difference along the length of the cabin, and only a miniscule one during lognitudinal acceleration.
What your mother might be experinecing is actually low frequency sound/vibration that can sometimes feel like fluctuations in pressure, a sort of a bubbly feeling in the ears.
This will vary greatly on type of aircraft, seating position, stage of flight etc, but as such it is not at all implausible that in general your mother experiences this in the rear portion of the cabin more than in the front. This can be especially prominent in planes with wing mounted jet engines, since the exhaust nozzle will be in front of the passengers sitting in the aft section.
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21$\begingroup$ The key is to separate the symptom (discomfort) from the cause (air pressure). The discomfort is valid, the cause is a hypothesis. This answer offers an alternate hypothesis without discounting the symptom. $\endgroup$– NelsonCommented Mar 14, 2023 at 0:36
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1$\begingroup$ Yep. In medicine it's never appropriate to deem false symptoms a patient describes simply because the inferred cause is implausible, or even totally out of the question. We still do not fully understand how human sensory systems work and especially how they intertwine with our psyche. Whatever we feel is always real in one way or another. $\endgroup$– Jpe61Commented Mar 14, 2023 at 13:25
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$\begingroup$ I agree vibration diagnosis. Loud white noise is often described as "pressure" by people experiencing it. Now, I disagree that wing mounted engines are worse. From experience, rear mounted engines are beyond compare louder when sitting in the back. $\endgroup$– UrQuan3Commented Mar 14, 2023 at 21:36
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$\begingroup$ My experience is different, but as this matter is subjective, your experience is as valid as mine. My recollection of rear engine noise is, that it is generally higher in pitch than that of wing mounted engines when sitting at the back, and thus not as "bubbly" in the ears. There are a huge amount of variables here... $\endgroup$– Jpe61Commented Mar 15, 2023 at 15:16
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That is not possible. The front and back of the cabin are not isolated by any means - so if there was a pressure difference, air will instantly start flowing from high pressure to low pressure in order to equalise the difference.
answered Mar 12, 2023 at 10:56
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7$\begingroup$ @xxavier You are right, but let's calculate the difference. The Boeing 737-800 has a cabin length of ~30m. Let's assume the ISA MSL air density of 1.225 kg/m³. Upon being subjected to an acceleration of 4m/s² (typical during takeoff), we obtain a force of 4.9 newtons from that cubic metre of air, and thus a pressure of 4.9 pascals. Multiplying that by 30, we get a pressure of ~1.5 hPa at the rear-end of the cabin, so the difference is negligible. $\endgroup$ Commented Mar 12, 2023 at 11:40
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5$\begingroup$ I totally agree with negligible, but very few non-engineers regularly deal with newtons, (other than the fig variety) or hPa. Can you translate that measurement into something relatable like going up a set of stairs? Most non fliers have experienced a change in air pressure going up in an elevator of a very tall building, or driving over a mountain pass. Can you make a similar comparison with your math here? (i.e. equivalent to a change of ____ feet in elevation...) $\endgroup$ Commented Mar 12, 2023 at 18:14
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11$\begingroup$ 150 Pa is 0.15% of an atmosphere or a difference of 12.5 m (41 ft) in elevation at sea level. $\endgroup$ Commented Mar 12, 2023 at 19:07
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6$\begingroup$ @HiddenWindshield While that does sound like a low pressure, it does not give you any indication of how a human ear will react to such a pressure differential. Michael Hall has a point in asking for an equivalent elevation change. $\endgroup$ Commented Mar 12, 2023 at 21:31
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4$\begingroup$ @Raketenolli Different people understand different visualizations, so having multiple of them is not a bad thing. $\endgroup$ Commented Mar 13, 2023 at 4:41
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There may be other factors than a pressure differential as the cause of ear irritation, such as greater pitching accelerations, because the rear of the plane is farther from the center of gravity. This could cause general motion sickness, and for some one with issues with their ears, in particular, the vestibular system$^1$, an increase in feelings of vertigo.
$^1$ see Pathologies
answered Mar 12, 2023 at 12:47
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2$\begingroup$ This is true. There's a lot going on inside the ear, and the sensations can get mixed up. $\endgroup$– Jpe61Commented Mar 12, 2023 at 14:53
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The difference in air pressure between front and back of the cabin will be trivial to the differences felt in pressurisation between the aircraft climbing and descending; or adjustments made to the ventilation controls.
Discomfort is far more likely to be due to the sound and vibration which will have a complex distribution depending on the type and layout of the aircraft and the extra motion typically felt in the rear seats being noticeably more bouncy, and during acceleration and deceleration phases.
You might find the centre of the aircraft is the best position rather than the front, and definitely not the rear.
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There is a very small difference in air pressure, but only when the plane is accelerating...
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6$\begingroup$ That negligible difference would be offset by the equally negligible gradient in the other direction when the plane decellerates. $\endgroup$– Ralph J ♦Commented Mar 12, 2023 at 13:25