Questions tagged [supersonic]
Use for questions relating to flight at speeds greater than sound and related effects from doing so.
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Is there ever a manned aircraft that was successfully flown faster than the Concorde?
I've always been interested in supersonic airliners, like the Concorde. However, my question is, is Concorde really the fastest manned aircraft in the world? Had there ever been another manned ...
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mig 21 variable geometry inlet cone specific operating range
what is the specific range of extraction and retraction for the variable
inlet cone of the MiG-21bis?
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Why is there an area of different density right at the nose of a plane going supersonic?
A normal subsonic enough, but still compressible flow will compress when it gets to the planes nose. But in supersonic flow, there won’t be this compression. There will just be a shockwave which turns ...
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What is the supersonic L/D of subsonic jetliner
Suppose you somehow managed to accelerate a typical jetliner oastbthe sound barrier and to whatever speed you wanted, climbing to keep lift constant. Is there any data on his the L/D evolves with Mach ...
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If sweep angles are high enough can supersonic wings use thick, rounded airfoils?
In lectures on aerodynamics, it's always emphasized that the effect of sweep is to lower the Mach number normal to the leading edge. In the context of supersonic flow, this ensure that the leading ...
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Why can you only hear an aircraft after the shockwave passes?
Why do you only hear engines and other noise from a jet going supersonic after the plane has passed? A lot of resources use this picture to illustrate :
This is cool and all, but say you changed the ...
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How are shockwaves able to refract?
How are shockwaves able to refract? As said in this,
When two shock waves collide, they interact with each other and produce complex patterns of compression, rarefaction, and reflection. The ...
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What happens when shockwaves interact?
As seen here, there are two T-38's going supersonic. What happens when those shockwaves interact? They seem to dissipate in some places on this photo when they interact. Any source online says that ...
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Why did the CF-105 cease production when it had such promising potential?
I have been reading about the CF-105 recently and noticed that although it was one of the most advanced aircraft of its era it was shut down by the Canadian government after one crashed in a freak ...
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Why is the upper surface shock further forward than the bottom shock on this airfoil?
If you look at this picture, you’ll see the shock on the upper surface is further forward on the wing, compared to the lower shock. Why is that?
(This is at Mach 0.9, as shown at the bottom of the ...
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What causes this vortex pattern on the slip line of a shockwave?
What are these little vortex patterns from on the slip line of these shocks? At first I thought it was vortex shedding, but it looks a tiny bit different to me (than vortex shedding).
You can see the ...
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Will supersonic flow return to subsonic through shocks over a flat surface?
Will supersonic flow return to subsonic through shocks over a flat surface? Imagine supersonic flow over a plate. Will it always try to return to subsonic through a series of normal shocks?
(Pretend ...
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Have any regulatory exceptions been made to allow a supersonic aircraft to fly over land so that it can follow the path of a solar eclipse?
It seems like there might be a good research reason to allow such a flight. As it's an unusual event, making this exception would not set much of a precedent.
It could potentially be a good way for ...
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Has a supersonic airplane with a truss-braced wing been studied/developed?
The X-66 truss braced jet is to be transonic. But have any published studies or development programs been done for a supersonic equivalent?
Seems like someone considered it, given that it allows ...
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Are oblique shocks formed at the leading edge-top surface of a wing?
Do oblique shocks form on the leading upper surface of a wing? I know bow shocks are formed there, but is that the same thing as I’m talking about? Oblique shocks would have to form there because the ...
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Are control surfaces less effective at supersonic speeds?
I am unsure if this is correct but this is my current explanation:
Once past supersonic speeds, the larger the speed the larger the divot of air pressure around the plane. Because these divots can get ...
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Tu-144 vs Concorde: which one of the two carried passengers first?
I know that the Tu-144 had the first prototype flight and it also beat Concorde in reaching supersonic speed, but what I am really curious to know is which design carried passengers first (not crew ...
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When an oblique shock forms, what happens to the normal shock that helped it form?
What happens to the normal shock that helped the oblique shock form, in the first shock of a lambda shock? Oblique shock waves form because :
"An oblique shock wave is a shock wave that, unlike a ...
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Why is the Busemann biplane not used?
A Busemann biplane greatly reduces wave drag It would allow a deeper, more efficient structure to support a wing with less wetted area and thus friction drag. It would seem trivial to tilt the ...
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How do canards reduce the X-59's sonic boom?
X-59
As of 2017, the ground noise was expected to be around 60 dB(A), about 1/1000 as loud as current supersonic aircraft. This was to be achieved by using a long, narrow airframe and canards to keep ...
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What determines the angle at which a shock will form?
What determines the angle that a shock will form? If you look at a lambda shock, you’ll see it isn’t straight up, but with an angle (both the front and rear part of the lambda shock).
The second ...
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How do supersonic warplanes deal with birds?
The Ruppell's Vulture can reach 11 km and can weigh 9kg. The Kori bustard can weigh 18kg. Many warplanes must break the sound barrier within reach of birds, especially on terrain hugging or sea ...
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Why are pressures equal across the slip line of a lambda shock, but density is not?
Why are pressures equal across the slip line of a lambda shock, but density is not? In this answer, it says this :
The surface Σ
is a slip line between zones 3 and 4. Velocities will be parallel ...
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How do boundary layers and shocks interact?
How do boundary layers and shocks interact? What difference is made with thinner and thicker BL's? I've recently been researching this topic, but at least for me there are no good search results on ...
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What causes the lambda shape in a shockwave?
What causes the λ (or lambda shape) in a shockwave? I heard it had something to do with the interaction between the shock and the boundary layer. If so, how do they interact and why does it make the ...
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Why do the shocks on the upper and lower surfaces of a wing stop at the trailing edge? [duplicate]
Why do the shocks on the upper and lower surfaces of a wing stop at the trailing edge? When going Mach 0.82, the shocks on the upper (and lower) surface don't go the whole chord length of the wing. (...
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How can the X-59 fly faster than the speed of sound without producing sonic booms? [duplicate]
Lately, NASA and Lockheed Martin revealed the X-59 which looks amazing. I read this article from NASA which already gives some insights of the X-59. The article claims that it will fly faster than the ...
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Am I correct with my thoughts of supersonic vs. subsonic flow?
So I'll just list a few things that I thought were correct. If there's anything I'm wrong about, I'd appreciate if someone could explain where I went wrong.
In supersonic (vs. subsonic) flow, the lift ...
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How do transonic or supersonic speeds affect lift distribution of the entire wing?
I've written a few questions about this topic, but this part I never asked.
How do supersonic or transonic speeds affect lift distribution over the whole wing? How does the root's changing pressure ...
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Why will air keep accelerating in Mach 1+ flow, when it would decelerate in subsonic flow?
So I was clarifying a few things in a comments section of an answer, and I had quite a few questions so I thought I'd ask my main one in a separate post.
In the second comment on this answer, it says ...
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How do you make sonic booms quieter
I was looking through several sources and I can’t find anything explaining how sonic booms can be muted. In the Lockheed Martin Quesst experimental airplane info it states that it supposedly has a “...
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Can an airplane propeller become supersonic?
Is it possible for an aircraft propeller to become supersonic?
I am not referring as for the aircraft, only the rotating blade.
I know it is extremely unlikely for a propeller plane to go supersonic, ...
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Can supersonic booms intensify as you fly longer?
If someone is flying just above Mach 1 for 10 minutes, I would think the sound/shock waves would just pile up and gain more energy, resulting in a very intense and loud boom when the pilot slows down.
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Does the X-59 comply with the "area rule"?
The Lockheed Martin X-59 was rolled out yesterday :-)
Brett Tingley, Watch NASA's sci-fi-looking X-59 'quiet' supersonic jet roll out of the hangar, August 2023.
I am no expert here (and no English ...
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Why arrow wings are more efficient than delta wings?
From page 29 of this slide (https://archive.aoe.vt.edu/mason/Mason_f/SupersonicPres.pdf), an arrow wing has higher lift slope and lower induced drag slope than a delta wing with a straight trailing ...
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Why do expansion fans cause oblique shock waves to curve?
When there is an expansion fan aft of an oblique shock such that its bounding mach waves intersect with the oblique shock, the oblique shock is curved in that region. What is the physical phenomenon ...
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Why do shockwaves move aft with camber/trailing edge deflection? [closed]
Why does a shockwave move further towards the trailing edge with increasing camber?
Also, is the shockwave the thing above the aerofoil or behind it?
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Heating of XB-70 vs. SR-71
The SR-71 was made with not tightly fitting fuel tanks and black paint, etc. to deal with aerodynamic heating. The XB-70 flew at essentially the same altitude and speed range, and was designed with ...
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Would an aircraft which could go through sound barrier at an over 25 degree climb avoid the sonic boom problem?
I read that the "cone" of the sonic boom is a cone of angle 25 degrees extending from the nose of the aircraft, centred on the axis of the aircraft.
I also read that the English Electric ...
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Why cut off the tips of a delta wing to form a cropped delta?
According to wikipedia, the reason to cut off the tips of a standard delta wing is
maintain lift outboard and reduce wingtip flow separation (stalling)
at high angles of attack
This type of delta ...
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Does an orbital trajectory reduce my required lift for high mach numbers?
when an aircraft is flying from let us say Paris to New York on a fixed altitude it is not flying on a straight line but on an orbital / circular trajectory around the earth. Assuming, the aircraft is ...
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Why were the Space Shuttle's elevons reversed, early in re-entry?
The veteran Space Shuttle commander Charlie Precourt writes, in the July 2022 issue of EAA's Sport Aviation, p. 38:
Another interesting reality about our flight controls was their
working essentially ...
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Jet Stream effects at 60.000 ft
Today's airplanes cruise at 40,000 feet. Easterly flight times are longer than their westerly components due to the direction of the jet stream. Comercial supersonic flights did/will cruise at 60,000 ...
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Can a Supersonic aerofoil have Max thickness near the middle?
I’m really unsure about this question:
Can a supersonic aerofoil have maximum thickness near the middle? so by middle of the aerofoil I mean 50% along the chord
Also, how would you actually calculate ...
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Why does the condensation cone disappears when the airplane starts flying supersonic
In this answer How are condensation cones created by supersonic airplanes? it is said that the condensation cones appear only when the airplane flies at speeds below Mach 1. I am wandering why does it ...
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What causes a normal shock wave on a wing?
I am wondering what causes a normal shockwave on a wing? I mean why does the airflow (that becomes supersonic over a part of the airfoil) slows down somewhere over that wing suddenly to a subsonic ...
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How to calculate the TAT (total air temperature) when a rocket is flying to space? [closed]
I checked this answer and I used the formula this answerer provided, but I couldn't get the data he/she presented in the graph. Did I do something wrong?
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Is a supersonic ekranoplan possible? Would mach 1+ would disable ground effect?
An ekranoplan takes advantage of ground effect to make it "fly" very economically.
Is it possible for an eraknoplan to fly at the speed of sound, how does ground effect work at such high ...
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Ice Protection System for supersonic aircraft
How does a supersonic transport aircraft IPS system work? Does it work only for the engine nacelle or both engine and wing. I was thinking only for nacelle since the wings are usually highly swept.
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Why can't supersonic flow work its way upstream?
I am reading this textbook today. And it described supersonic flow as follows:
In a supersonic flow, because the local flow velocity is greater than the speed of sound, disturbances created at some ...