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The J-20-engine discussion is over and other speculative topics ... to separate from the J-20-news !

" but since the WS-10 is China's most successful - and so far only - available high-thrust engine it is the only other explanation.

So it is almost the last straw to cling to, not to admit, it can be only an AL-31"


As i said before, I would pick AL-31 over WS-10 any time. WS-10 simply doesn't make any sense. It has no similarity whatsoever. It couldn't even pass, the simple appearance test.

Unlike the AL-31 supporters, who loves to do nozzle comparisons, the WS-10 supporters have never bothered to do so. One can easily see why. No need to. Even a one-eyed man can see they have no similarities.

I can excuse the AL-31 supporters, for being mistaken, but those WS-10 theory supporters, really have lost their minds or eyes, for believing in, such ridiculous theory.

It makes no sense, whatsoever.
 
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" but since the WS-10 is China's most successful - and so far only - available high-thrust engine it is the only other explanation.

So it is almost the last straw to cling to, not to admit, it can be only an AL-31"


As i said before, I would pick AL-31 over WS-10 any time. WS-10 simply doesn't make any sense. It has no similarity whatsoever. I can excuse the AL-31 supporter for being mistaken, but those WS-10 theory supporters really have lost their minds or eyes.
:blah::blah::blah:
 
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"If the J-20 is using an imported Russian engine, chances are it is highly underpowered."

I don't think Figaro still believes in the AL-31-FN-M2 theory.

He is merely remind us that, if that's the case, J-20 will be underpowered. But J-20 never showed any signs of being underpowered. Quite the opposite, it could lift itself vertically in a sustained manner, without AB.
I can show you lots of video of 4 and 4.5 gen jets can do vertical w/o of use of afterburner even our JF-17 can easily do it w/o Afterburner Mr @Asok
 
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"If the J-20 is using an imported Russian engine, chances are it is highly underpowered."

I don't think Figaro still believes in the AL-31-FN-M2 theory.

He is merely remind us that, if that's the case, J-20 will be underpowered. But J-20 never showed any signs of being underpowered. Quite the opposite, it could lift itself vertically in a sustained manner, without AB.
here F-16 climbing without use of A/B
In this clip there is no shock diamond or flame coming out from the engine
In this clip there are clearly shows that shock diamonds or flame coming out from the engine:p:
you don't know what is shock diamonds are so here its definations
https://en.wikipedia.org/wiki/Shock_diamond
 
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here F-16 climbing without use of A/B
In this clip there is no shock diamond or flame coming out from the engine
In this clip there are clearly shows that shock diamonds or flame coming out from the engine:p:
you don't know what is shock diamonds are so here its definations
https://en.wikipedia.org/wiki/Shock_diamond
Asok is clearly right my friend. The J-20 did NOT need to use afterburners during its Zhuhai demonstration. Hence why all of us believe it has a powerful engine regardless of origin.
 
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"Asok is clearly right my friend. The J-20 did NOT need to use afterburners during its Zhuhai demonstration. Hence why all of us believe it has a powerful engine regardless of origin."

This guy @pakistanipower don't even know, what is Afterburner or Vertical climb is. The videos he listed clearly showed the F-16 used the AfterBurner (the videos showed it has a red hot flaming butt) all the way, and there is NO vertical climb demonstrated.

And he clearly doesn't agreed, with the high school level physics, that to do a sustained vertical climb (not a loop or mere high angle climb), one needs to have a TWR > 1, or F/W > 1.

What a joke!

https://www.grc.nasa.gov/www/K-12/airplane/fwrat.html


upload_2017-8-29_8-42-45.png


Note the last line, I highlighted.

F/W > 1.0 (TWR > 1.0 ) Can Accelerate Vertically.


"There are four forces that act on an aircraft in flight: lift, weight, thrust, and drag. Forces are vector quantities having both a magnitude and a direction. The motion of the aircraft through the air depends on the relative magnitude and direction of the various forces. The weight of an airplane is determined by the size and materials used in the airplane's construction and on the payload and fuel that the airplane carries. The weight is always directed towards the center of the earth. The thrust is determined by the size and type of propulsion system used on the airplane and on the throttle setting selected by the pilot. Thrust is normally directed forward along the center-line of the aircraft. Lift and drag are aerodynamic forces that depend on the shape and size of the aircraft, air conditions, and the flight velocity. Lift is directed perpendicular to the flight path and drag is directed along the flight path.

Just as the lift to drag ratio is an efficiency parameter for total aircraft aerodynamics, the thrust to weight ratio is an efficiency factor for total aircraft propulsion. From Newton's second law of motion for constant mass, force F is equal to mass m times acceleration a:

F = m * a

If we consider a horizontal acceleration and neglect the drag the net external force is the thrust F. From the Newtonian weight equation:

W = m * g

where W is the weight and g is the gravitational constant equal to 32.2 ft/sec^s in English units and 9.8 m/sec^s in metric units. Solving for the mass:

m = W / g

and substituting in the force equation:

F = W * a / g

F / W = a / g

F/W is the thrust to weight ratio and it is directly proportional to the acceleration of the aircraft. An aircraft with a high thrust to weight ratio has high acceleration. For most flight conditions, an aircraft with a high thrust to weight ratio will also have a high value of excess thrust. High excess thrust results in a high rate of climb. If the thrust to weight ratio is greater than one and the drag is small, the aircraft can accelerate straight up like a rocket. Similarly, rockets must develop thrust greater than the weight of the rocket in order to lift off .

NOTE: We must be very careful when using data concerning the thrust to weight ratio. Because airframes and engines are produced by different manufacturers and the same engine can go into different airframes, the thrust to weight ratio of the engine alone is often described in the literature. High thrust to weight is an indication of the thrust efficiency of the engine. But when determining aircraft performance, the important factor is the thrust to weight of the aircraft, not just the engine alone. Another problem occurs because the thrust of an engine decreases with altitude while the weight remains constant. Thrust to weight ratios for engines are often quoted at sea level static conditions, which give the maximum value that the engine will produce."
 
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I once read that @pakistanipower guy claimed as an engineer though I cannot recall in which field.

However, what I don't see from him as an engineer is the systematic and methodical explanation to prop his arguments... instead he resorts to the terse, agitative remarks put in the distinctive color and bold like this example, repeatedly...:D:lol::P very cool!!
 
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He is an engineer? I really doubt, he has any technical background.

This @pakistanipower guy only knows, how to give one liner replies, that has no logic or informational content, whatsoever. SAD!
 
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He is an engineer? I really doubt, he has any technical background.

This @pakistanipower guy only knows, how to give one liner replies, that has no logic or informational content, whatsoever. SAD!
Even a non-engineer could distinguish the appearance of an afterburner. I don't have an engineering profession but I'm still able to differentiate two obvious settings. I will repeat ... the J-20 did not engage afterburners at Zhuhai or in any of its high g maneuvers ... @PP needs to google image afterburner settings ... :hitwall:
 
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"Asok is clearly right my friend. The J-20 did NOT need to use afterburners during its Zhuhai demonstration. Hence why all of us believe it has a powerful engine regardless of origin."

This guy @pakistanipower don't even know, what is Afterburner or Vertical climb is. The videos he listed clearly showed the F-16 used the AfterBurner (the videos showed it has a red hot flaming butt) all the way, and there is NO vertical climb demonstrated.

And he clearly doesn't agreed, with the high school level physics, that to do a sustained vertical climb (not a loop or mere high angle climb), one needs to have a TWR > 1, or F/W > 1.

What a joke!

https://www.grc.nasa.gov/www/K-12/airplane/fwrat.html


View attachment 421720

Note the last line, I highlighted.

F/W > 1.0 (TWR > 1.0 ) Can Accelerate Vertically.


"There are four forces that act on an aircraft in flight: lift, weight, thrust, and drag. Forces are vector quantities having both a magnitude and a direction. The motion of the aircraft through the air depends on the relative magnitude and direction of the various forces. The weight of an airplane is determined by the size and materials used in the airplane's construction and on the payload and fuel that the airplane carries. The weight is always directed towards the center of the earth. The thrust is determined by the size and type of propulsion system used on the airplane and on the throttle setting selected by the pilot. Thrust is normally directed forward along the center-line of the aircraft. Lift and drag are aerodynamic forces that depend on the shape and size of the aircraft, air conditions, and the flight velocity. Lift is directed perpendicular to the flight path and drag is directed along the flight path.

Just as the lift to drag ratio is an efficiency parameter for total aircraft aerodynamics, the thrust to weight ratio is an efficiency factor for total aircraft propulsion. From Newton's second law of motion for constant mass, force F is equal to mass m times acceleration a:

F = m * a

If we consider a horizontal acceleration and neglect the drag the net external force is the thrust F. From the Newtonian weight equation:

W = m * g

where W is the weight and g is the gravitational constant equal to 32.2 ft/sec^s in English units and 9.8 m/sec^s in metric units. Solving for the mass:

m = W / g

and substituting in the force equation:

F = W * a / g

F / W = a / g

F/W is the thrust to weight ratio and it is directly proportional to the acceleration of the aircraft. An aircraft with a high thrust to weight ratio has high acceleration. For most flight conditions, an aircraft with a high thrust to weight ratio will also have a high value of excess thrust. High excess thrust results in a high rate of climb. If the thrust to weight ratio is greater than one and the drag is small, the aircraft can accelerate straight up like a rocket. Similarly, rockets must develop thrust greater than the weight of the rocket in order to lift off .

NOTE: We must be very careful when using data concerning the thrust to weight ratio. Because airframes and engines are produced by different manufacturers and the same engine can go into different airframes, the thrust to weight ratio of the engine alone is often described in the literature. High thrust to weight is an indication of the thrust efficiency of the engine. But when determining aircraft performance, the important factor is the thrust to weight of the aircraft, not just the engine alone. Another problem occurs because the thrust of an engine decreases with altitude while the weight remains constant. Thrust to weight ratios for engines are often quoted at sea level static conditions, which give the maximum value that the engine will produce."
And Mr @Asok F-16 don't have TWR of 1 in the clean configurations:enjoy: and can you show me where shock diamonds flames come out from engine on my first clip show me Mr @Asok and here are thrust to weight of F-16
F-16
General characteristics


Performance

 
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And Mr @Asok F-16 don't have TWR of 1 in the clean configurations:enjoy: and can you show me where shock diamonds flames come out from engine on my first clip show me Mr @Asok and here are thrust to weight of F-16
F-16
General characteristics


Performance

What are you trying to prove here? The J-20 did not engage afterburners in similar maneuvers where the F-22 would otherwise need to. This proves that the J-20 has a good combination of aerodynamic design and engine thrust to ensure excellent transonic maneuverability.

He is an engineer? I really doubt, he has any technical background.

This @pakistanipower guy only knows, how to give one liner replies, that has no logic or informational content, whatsoever. SAD!
@pakistanipower really needs to stop using bolded any highlighted letters ... this practice is just flame bait. The users on the Chinese section of PDF should be much more civil than the others ...
 
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What are you trying to prove here? The J-20 did not engage afterburners in similar maneuvers where the F-22 would otherwise need to. This proves that the J-20 has a good combination of aerodynamic design and engine thrust to ensure excellent transonic maneuverability.
i'm trying to correct jester Mr @Asok
 
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pakistanipower don't really know what is difference, between Dry Thrust (w/o afterburner), and Wet thrust (w. afterburner).

  • Empty weight: 18,900 lb (8,570 kg)
  • Internal fuel: 7,000 pounds (3,200 kg)
Thrust/weight: 1.095 (1.24 with loaded weight & 50% internal fuel)

So, from the above, the empty weight of F-16, plus, 50% internal fuel is:

8,570 kg + (3,200kg * 0.50) = 10,170kg

The Dry Thrust (w/o afterburner) = 76.3 kN or 7,780kg
Wet Thrust (w. afterburner) = 127 kN = 12,950kg

Wet Thrust > Flying Weight > Dry Thrust
12,950kg > 10,170kg > 7,780kg

Dry Thrust to Weight Ratio = 0.765
Wet thrust to Weight Ratio = 1.27

So, we can see, the TWR, w/o AB = 0.765, which is less than 1.0. That means the F-16 can not lift itself vertically, without the use of AB.

And Wet thrust to Weight Ratio = 1.27, so it must turn the AB on, if the pilot wants to do a vertically climb, when carrying 50% internal fuel.

The shock diamond is only visible, when the AB is turned on full blast, not when its only just turned on moderately, which you see only the flaming red butt.

@pakistanipower said he has an engineering background. I wonder what engineering school, he went to. He doesn't seem to have an education, beyond the elementary school.

Otherwise, he would not have failed to do such elementary calculations.
 
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