bigpicture7
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While your pedantic point that planes are not literally silent while landing is correct, the spirit of your post is wrong. They are in fact much quieter while landing:
https://www.broward.org/Airport/Community/Documents/Stage3and4presentation.pdf
The charts in that presentation show most modern planes are around 80-90 dB if you are directly under the approach. That noise level dissipates quickly to <80 dB if you are more than a quarter mile from the flight path. Also once the plane is 6-7 miles away from the runway the noise level drops below 80 dB. On the other hand, when taking off, the range of 80+ dB noise is much wider.
Absolutely; planes are quieter on landing than take-off. You have similar flap and landing gear positions at both. On takeoff you have the substantial addition of thrust generation (hence why engine designers have spent so much time and money on nacelle and nozzle redesigns - ala 787 chevroned design); on landing you have the addition of spoilers. Thrust generation >>> spoilers; hence takeoff is louder than landing.
As for:
as planes are "gliding" for a landing they have deployed all manner of non-aerodynamic appurtenances all of which interrupt or chaoticize the air stream. Some of messing with the clean stream of air is of course intentional such as flaps and slats and some such a wheels are needed for other functions
Not exactly; flaps' purpose is to increase the amount of lift per air speed at the known expense of added drag. Flaps make the wing more aggressive; their purpose is not chaotic interruption of the airstream; their effect on laminar flow beyond the boundary layer is just as important. Sure, Landing gear produces chaotic turbulence. Spoilers are designed primarily to burn off speed and also have a somewhat chaotic effect. None of these things come close to the effects of engine thrust.
Also of importance is that modern FADEC engine control systems (and improved control system bandwidth) have reduced the need for throttle surges to stay aligned with glide slope (a la 70's era DC-9s where you hear the auto throttle surging up and down as the plane attempts to maintain glide slope). Hence you hear less engine at landing than you used to hear with older planes.