I thought we already agreed that the color of the afterburner is blue?
J-20... The New Generation Fighter II
- Thread starter Asymptote
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MiG-29
Banned Idiot
Re: J-20... The New Generation Fighter
Being bigger does not mean better, why? well simple being bigger means it is heavier, if the F-22 weighs 19700kg empty and around 38000kg at full weight then the J-20 passes the 22000kg empty weight and probably 41000-42000kg max weight if it uses equivalent technologies, then this translates into the need of having higher yield engines in the region of 18000-19000kg of thrust, try to make engines small enough and having such yield is quiet complex, with enough reliability, yes the Backfire and Tu-160 have engines with such yield but are bigger an won`t fit into the J-20 and have higher SFC, so fitting a NK-44 engine into the J-20 won`t fix anything just make it heavier bigger and easier to spot, then the J-20 will need TVC to reduce its canard deflections for trimming, this means that with equal technology it will have a higher RCS than the F-35.
So being bigger could simply mean it is slower, less agile and probably more visible than the F-22 at eyeball range, infrared and radar.
adding flat nozzles will add more weight so still it will have less ability to reduce IR signature due to hotter gases and to rounded nozzles, to be honest the J-20 does not seem to be better than the F-22
Being bigger does not mean better, why? well simple being bigger means it is heavier, if the F-22 weighs 19700kg empty and around 38000kg at full weight then the J-20 passes the 22000kg empty weight and probably 41000-42000kg max weight if it uses equivalent technologies, then this translates into the need of having higher yield engines in the region of 18000-19000kg of thrust, try to make engines small enough and having such yield is quiet complex, with enough reliability, yes the Backfire and Tu-160 have engines with such yield but are bigger an won`t fit into the J-20 and have higher SFC, so fitting a NK-44 engine into the J-20 won`t fix anything just make it heavier bigger and easier to spot, then the J-20 will need TVC to reduce its canard deflections for trimming, this means that with equal technology it will have a higher RCS than the F-35.
So being bigger could simply mean it is slower, less agile and probably more visible than the F-22 at eyeball range, infrared and radar.
adding flat nozzles will add more weight so still it will have less ability to reduce IR signature due to hotter gases and to rounded nozzles, to be honest the J-20 does not seem to be better than the F-22
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Take care bro, Just to be caution in case you will ' invited for tea '..
MiG-29
Banned Idiot
continuos curvature is simple, it means if you align an edge into an angle that sends the radar energy away from the radar you can use rounded surfaces up to a level but rounded surfaces send the radar radiation at different directions, however aligning these rounded surfaces into an angle of reflection with a normal that sends away the radiation will sufice to avoid detection.
In example the rounded leading edge of the B-2 or the F-22`s radome and canopy
MiG-29
Banned Idiot
The J-20 is around 2 meters longer than the F-22 without probe, the F-22 is almost 19 meters, the J-20 easily is 21 meters without probe and 23 meters with it
you guys have this bit wrong...
Yf-23 length is just above 20 meters. the production version would be longer.
It uses about the same class of engine as YF-22/F-22.
It slightly heavier or same both in MTOW and empty as YF-22.
It has a longer range and higher top speed than F-22 or the YF-22. by a wide shot.
It has a higher super cruise speed and range than F-22.
btw, It's top speed is still classified.
The only thing that's lacking vs YF-22 was manuevability.
J-20 with its closed couple canards. might, I say might because from the reading materials certainly that's what the aerodynamicists intend to do from the beginning, donno if he succeeded or not....
that he has both high-aoa low speed regime and high speed cruise down. with this closed coupled canard design.
Than we might be looking at a beast that has the speed and range of YF-23 and manuevability of YF-22.
Yf-23 length is just above 20 meters. the production version would be longer.
It uses about the same class of engine as YF-22/F-22.
It slightly heavier or same both in MTOW and empty as YF-22.
It has a longer range and higher top speed than F-22 or the YF-22. by a wide shot.
It has a higher super cruise speed and range than F-22.
btw, It's top speed is still classified.
The only thing that's lacking vs YF-22 was manuevability.
J-20 with its closed couple canards. might, I say might because from the reading materials certainly that's what the aerodynamicists intend to do from the beginning, donno if he succeeded or not....
that he has both high-aoa low speed regime and high speed cruise down. with this closed coupled canard design.
Than we might be looking at a beast that has the speed and range of YF-23 and manuevability of YF-22.
MiG-29
Banned Idiot
you guys have this bit wrong...
Yf-23 length is just above 20 meters. the production version would be longer.
It uses about the same class of engine as YF-22/F-22.
It slightly heavier or same both in MTOW and empty as YF-22.
It has a longer range and higher top speed than F-22 or the YF-22. by a wide shot.
It has a higher super cruise speed and range than F-22.
btw, It's top speed is still classified.
The only thing that's lacking vs YF-22 was manuevability.
J-20 with its closed couple canards. might, I say might because from the reading materials certainly that's what the aerodynamicists intend to do from the beginning, donno if he succeeded or not....
that he has both high-aoa low speed regime and high speed cruise down. with this closed coupled canard design.
Than we might be looking at a beast that has the speed and range of YF-23 and manuevability of YF-22.
The J-20 has a few things different from the YF-23, first it has a F-22`s style fuselage, not the same design of the YF-23, it is longer than the F-22 and has a longer rear fuselage so it makes more drag, the canards are not arranged as on the J-10 and the wing is quit aft, the YF-23 has a similar fuselage to the PAKFA, for the J-20 to have similar performance to the F-22 needs similar levels of drag/lift ratio, the F-22 achieves that by using Thrust Vectoring control nozzles thus reducing wing flaps or tail deflections; the canard always creates more drag because it is in front of the airflow of the wing thus it sheds a wake of turbulance that rest lift for the wing.
If the J-20 weighs 21000 or 22000kg at empty weigh and 40000 to 42000kg at max take off weight in order to have a 1:1 thrust to weight ratio will need at least engines of 19000 kg of thrust.
I think is very unlikely the J-20 has lighter or equivalent empty weight to the F-22 or better engines , thus having more drag it won`t have better agility, range or supercruise than the F-22.
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I am curious what gives you the confidence to speak about lift and drag ratio? longer fuselage means more drag?
fineness ratio? ever heard of it?
Well,
I can't argue with some one who has an eye-ball wind tunnel, can I?
First, J-20's wings have higher swap angle. It has less drag than F-22 when going straight (more drag when turning).
It has smaller vertical stabilizers (40% smaller). That's less drag and weight.
Based on public published papers by Chengdu designers, the delta/lifting body/canard configuration generates 80% more lift than delta only.
There is also unconfirmed rumor that J-20 has full control with the main wings only without canards. That means at high speed, it can use wing flaps to control, instead of canards.
So, while at a glance, J-22 has a large body. It comes down to whether the additional weight is canceled out by the much smaller vertical stabilizers. It may still be heavier, but I doubt the difference is that big. Remember J-8B (which does not use any modern materials) is 21m long, but only 9ton+ empty.
On lift, I am pretty sure J-22 has better lift than F-22.
On drag, I would call them even. Again, the additional drag created by longer body is canceled out by smaller vertical stabilizers.
MiG-29
Banned Idiot
well you will need to prove the rear cross section of the aft fuselage of the J-20 is narrower than the F-22`s specially when the widest part of the wing of the J-20 is at the aft of the aircraft, longer fuselages also generate more boundary layer thus drag is higher
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