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for large Jumbos like the Airbus A380 and the Boeing 747 - 800 at maximum thrust at take off, does the compressor section of a jet engine creates a depression in front of it, due to air be sucked at a great rate. Is the air sucked in by the jet engine replaced by the artmosphere as fast as it is sucked. How does this compare with the aircraft at cruise speed and altitude and what impact does it have on aerodynamics and air resistance relative to speed with which it is replaced and the speed of the aircraft also considering the large area around the aircrat with which theair is sucked


marked as duplicate by ymb1, Ralph J, fooot, xxavier, Carlo Felicione Jan 26 '18 at 5:40

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  • $\begingroup$ Your question would be better received if you ask "does the compressor section of a jet engine creates a depression in front of it, due to air be sucked at a great rate." $\endgroup$ – mins Jan 25 '18 at 18:33
  • $\begingroup$ @ymb1: This answer provides some information, though not much, and some uncertainty remains about the lower pressure extent . $\endgroup$ – mins Jan 25 '18 at 18:44
  • $\begingroup$ I tried to answer as far as I did understand the question. Could you please rephrase your question with respect to the section about friction. I am not sure what you are asking here. $\endgroup$ – rul30 Jan 25 '18 at 20:20
  • $\begingroup$ If the air wasn't replaced you'd hav a vacuum... Also you really need to improve on the wording of your questions. If you need help, ask in chat. Finally, there's no such thing as a Boeing 747-800, it's a 747-8, see here $\endgroup$ – Notts90 Jan 25 '18 at 20:54

(I am not entirely sure if I understood the question, but I hope you are asking how the air-flow into the jet-engine changes between stand-still and flight.)

On the ground (stand-still and taxi) the intake of a jet-engine will "suck" in the air. This means the pressure in the inlet section is lower than the ambient pressure.
In-flight the engine is "rammed" into the air. Here the pressure in the inlet-section is higher than the ambient pressure (see sketch from Wikipedia).

enter image description here

  • $\begingroup$ +1. Exactly the picture I was thinking of, and I think that's all you can say, and all that is needed... $\endgroup$ – Penguin Jan 25 '18 at 22:05

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