Linked Questions
32 questions linked to/from Why can't jet engines operate with supersonic air and how do they slow it down?
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How does a supersonic jet engine differ from a subsonic jet engine? [duplicate]
All jet engines have the same method of air flowing into the engine, which is compressed and ignited.
What can engine designers do to make an engine design create more thrust? For example, what is ...
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How does a wing mounted jet engine on a supersonic airplane prevent the interference in the flow due to Shock? [duplicate]
Wing mounted jet engines face the free stream at Mach number 1 or above, and they work perfectly for Mach numbers below 1 as well, even though the free stream characteristics change a lot after Mach 1....
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Is it possible to control the inlet Mach no. of the engine during flight? [duplicate]
While calculating the off design conditions of the engine, we need to know the off design characteristics, such as inlet additive drag. In the book Mechanics of Flight, by Warren F. Phillips, its ...
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Why is a reciprocating engine air intake a reverse bell shape? [duplicate]
Why would this inlet for the induction system get wider as the air approaches the filter?
What net effect does this have on intake pressure, and how would an inlet that starts wide and then narrows ...
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Why is the maximum speed of current fighter aircraft lower than those from the 1960's and 1970's?
While reading about the characteristics of the newest fighter aircraft, I observed that their maximum speed is lower than of the aircraft in the same roles half a century ago.
For example, the iconic ...
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Why is the nose of the Mig-21 shaped so differently compared to other fighter aircraft?
If you look at this picture below, you will notice that the nose portion of the Mig-21 has a unique conical shape which is completely different from the nose of the F-16.
(Source)
(Source)
So what ...
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What determines the maximum altitude a plane can reach?
What factors determine the maximum altitude for a plane?
Is it limited by wing design, engine thrust, and so on?
Is there a formula by which one can calculate the maximum altitude a plane can reach?
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Why do gases in the combustion chamber only flow one direction to the gas turbine in a jet engine?
As far as I know from the working principle of jets engines, compressed air in the combustion chamber (or combustion canister) is mixed with fuel. The ignited mixture expands backwards to turn the ...
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If jets carried pure O2 to use for combustion, would they be more efficient?
Air is around 21% Oxygen. The bulk of air is non-flammable Nitrogen. Wouldn't surrounding the jet fuel with only O2 create more efficient and clean combustion?
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Are the fastest moving pieces of a jet engine supersonic?
A jet engine is composed of fast moving pieces. Those pieces are moving into an airmass different form the ambient airmass the aircraft is flying into.
The turbine pieces are spinning quite fast, ...
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Why do military turbofan engines use a low bypass ratio?
I know that the most civilian engines use a high bypass ratio which is good for fuel economy and noise reduction.
What prevents military engines from using the same technology instead of opting for ...
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Can I simply use multiple turbojet engines to fly supersonic?
the jet engine FJ33 produced by Williams International produces around 6 kN thrust (maximum, at sea level).
Imagine: to fly supersonic, I need for my aircraft 9 kN of continious thrust.
I am wondering ...
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Why do jet engines have a maximum speed?
What's the scientific background behind a jet engine's top speed? Jet engines increase efficiency at higher airflow rates, so why does the efficiency stop increasing at some point?
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How is supercruise achieved?
Wikipedia article tells that supercruise is a condition when an aircraft can achieve velocities above Mach one without using the highly inefficient afterburners. But still, there are not a lot of ...
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Can a convergent nozzle be used for a supersonic jet engine?
Can a supersonic fighter incorporate a convergent nozzle or does it always have to be a convergent-divergent nozzle?
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