Chengdu J-20 5th Generation Aircraft News & Discussions
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siegecrossbow
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The second batch of prototypes consisted of 2002 and 2003 so there are at least three excluding the static testing model.
Martian2
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J-20 Mighty Dragon "2002" first flight
J20
Extended version follows:
J20
[Note: Thank you to Frank Lau for the video links.]
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J-20 Mighty Dragon has three times the combat radius of the F-22 Raptor
I view the J-20 Mighty Dragon as a large F-22. It has greater range and a similar payload. Two side-bays for short-range air-to-air missiles and a main weapon bay to carry medium-range air-to-air missiles.
J-20 combat range: 1,243 miles (see http://en.wikipedia.org/wiki/Chengdu_J-20#Specifications)
F-22 combat range: 471 miles (see http://en.wikipedia.org/wiki/Lockheed_Martin_F-22_Raptor#Specifications)
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The cube root of 3
In an earlier post, I made the claim that the J-20 Mighty Dragon has a far greater combat radius (e.g. 1,243 miles) than the F-22 (e.g. 471 miles).
Obviously, it is indisputable the J-20 has significantly longer range than the F-22. Your eyes can easily note the larger physical size of the J-20 in a photographic comparison (with the pictures normalized to match the sizes of the pilots' helmets and airplane wheels).
Anyway, we're moving onward to a mathematical analysis. For a J-20 to have three times the range of a F-22, it needs to carry three times the fuel. Volume is determined by three dimensions (e.g. length, width, and height).
To carry three times the fuel of a F-22, the J-20 must have a fuel tank that is three times larger. The cube root of three will indicate how much larger the J-20 fuel tank must be in physical dimensions.
The cube root of 3 = 1.44
Thus, if the J-20 fuel tank is 1.44 times longer, 1.44 times wider, and 1.44 times taller than the F-22 then the J-20 has three times the fuel load of the F-22.
Anyway, I don't have the schematics for the J-20 and F-22. However, it is entirely plausible that the J-20 fuel tank is 1.44 times larger than the F-22 in all three dimensions. Therefore, it is credible the J-20 has three times the combat radius of the F-22. The US Air Force screwed up in building an air superiority fighter with such a short range.
China can easily bomb (with ballistic, cruise, or MLRS missiles) any potential airfields that may serve as a base of operations for the F-22. Without a base to resupply fuel and ammunition, the F-22 is out of action in the Chinese theater of operation.
[Note: I am aware the J-20 will weigh a little more than the F-22 and it will have to carry a little more than three times the fuel load. However, this is offset by more lift from the canards and the calculations are meant to be approximate to illustrate a point.]
J20
Extended version follows:
J20
[Note: Thank you to Frank Lau for the video links.]
----------
J-20 Mighty Dragon has three times the combat radius of the F-22 Raptor
I view the J-20 Mighty Dragon as a large F-22. It has greater range and a similar payload. Two side-bays for short-range air-to-air missiles and a main weapon bay to carry medium-range air-to-air missiles.
J-20 combat range: 1,243 miles (see http://en.wikipedia.org/wiki/Chengdu_J-20#Specifications)
F-22 combat range: 471 miles (see http://en.wikipedia.org/wiki/Lockheed_Martin_F-22_Raptor#Specifications)
----------
The cube root of 3
In an earlier post, I made the claim that the J-20 Mighty Dragon has a far greater combat radius (e.g. 1,243 miles) than the F-22 (e.g. 471 miles).
Obviously, it is indisputable the J-20 has significantly longer range than the F-22. Your eyes can easily note the larger physical size of the J-20 in a photographic comparison (with the pictures normalized to match the sizes of the pilots' helmets and airplane wheels).
Anyway, we're moving onward to a mathematical analysis. For a J-20 to have three times the range of a F-22, it needs to carry three times the fuel. Volume is determined by three dimensions (e.g. length, width, and height).
To carry three times the fuel of a F-22, the J-20 must have a fuel tank that is three times larger. The cube root of three will indicate how much larger the J-20 fuel tank must be in physical dimensions.
The cube root of 3 = 1.44
Thus, if the J-20 fuel tank is 1.44 times longer, 1.44 times wider, and 1.44 times taller than the F-22 then the J-20 has three times the fuel load of the F-22.
Anyway, I don't have the schematics for the J-20 and F-22. However, it is entirely plausible that the J-20 fuel tank is 1.44 times larger than the F-22 in all three dimensions. Therefore, it is credible the J-20 has three times the combat radius of the F-22. The US Air Force screwed up in building an air superiority fighter with such a short range.
China can easily bomb (with ballistic, cruise, or MLRS missiles) any potential airfields that may serve as a base of operations for the F-22. Without a base to resupply fuel and ammunition, the F-22 is out of action in the Chinese theater of operation.
[Note: I am aware the J-20 will weigh a little more than the F-22 and it will have to carry a little more than three times the fuel load. However, this is offset by more lift from the canards and the calculations are meant to be approximate to illustrate a point.]
air marshal
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Chengdu J-20 could enter service by 2018
May 18, 2012
By DAVE MAJUMDAR
The stealthy Chengdu J-20 fighter could enter operational service by early 2018 and join a rapidly improving Chinese military armed with long-range strike weapons, new unmanned air vehicles and command and control aircraft fleets, the US Department of Defense says in an annual assessment.
The J-20 is "still in a prototype phase," says David Helvey, the acting deputy assistant secretary of defense for East Asia for the US Department of Defense.
"So we'd like to be able to continue to monitor it--to continue monitor developments on that to understand exactly what China may intend to use it for, and I wouldn't want to speculate at this point for what those specific missions would be," he adds.
But the report itself says that the J-20 reflects "China's ambition to produce a fighter aircraft that incorporates stealth attributes, advanced avionics, and supercruise-capable engines."
The first J-20 prototype started flight tests in January 2011 and a second example started flying earlier this month. But the US government is adamant that the aircraft will not enter frontline squadron service until much later this decade.
"We expect the J-20 to achieve an effective operational capability no sooner than 2018," Helvey says. "That reflects our judgment and interpretation of how far they are along in doing the research and development and flight testing of the prototypes," he adds.
Operational capability as the DoD defines it means that there should be enough aircraft, weapons and trained air crew to conduct real-world missions, Helvey says.
The DoD also believes that the Chinese have an interest in developing new unmanned aircraft.
"We know that China is interested in developing unmanned air systems, and they have in the past acquired a number of different types of UAVs," Helvey says. "This report doesn't make a net assessment between China's capabilities for unmanned air systems and US capabilities, but that is an area that China is interested in developing."
China has a number of unmanned aerial vehicles including the Israeli-made Israel Aerospace Industries Harpy and a number of domestic types.
Meanwhile, the People's Liberation Army Air Force (PLAAF) is not neglecting its long-range strike capabilities. The country is upgrading its Tupolev Tu-16 Badger-derived Xian B-6 bomber fleet with a new, longer-range variation, which will be armed with new long-range cruise missiles, the report says.
The Chinese are also developing several types of airborne early warning and control system (AWACS) aircraft. These include the Shaanxi Y-8 Moth, based on the Antonov An-12, and the KJ-2000, based on the Ilyushin IL-76 airlifter, the report says.
Meanwhile, China's navy is moving on getting its first aircraft carrier into service. The refurbished Soviet-built ship started sea trials last August, but it not yet operational.
"This aircraft [carrier] could become operationally available to China's navy by the end of this year," Helvey says. "But we expect it'll take several additional years for an air group to achieve a minimal operational capability aboard the aircraft carrier."
The report also indicates that China is probably designing and possibly building in own indigenous carriers.
While China's public statements on its defence budget about $106 billion for 2012, the DoD estimates that the Chinese will actually spend more than $180 billion.
Helvey says the DoD believe that many aspects of China's military modernization actually comes from different spending accounts rather than the main defence budget. Foreign acquisitions such as Russian-built fighters are counted the same way.
"For example, we think that some of their nuclear forces modernisation occurs off budget," he says. "So when you add all of that together, that helps us to develop, I think, a more accurate estimate of what the totality of the military expenditure is."
Chengdu J-20 could enter service by 2018
May 18, 2012
By DAVE MAJUMDAR
The stealthy Chengdu J-20 fighter could enter operational service by early 2018 and join a rapidly improving Chinese military armed with long-range strike weapons, new unmanned air vehicles and command and control aircraft fleets, the US Department of Defense says in an annual assessment.
The J-20 is "still in a prototype phase," says David Helvey, the acting deputy assistant secretary of defense for East Asia for the US Department of Defense.
"So we'd like to be able to continue to monitor it--to continue monitor developments on that to understand exactly what China may intend to use it for, and I wouldn't want to speculate at this point for what those specific missions would be," he adds.
But the report itself says that the J-20 reflects "China's ambition to produce a fighter aircraft that incorporates stealth attributes, advanced avionics, and supercruise-capable engines."
The first J-20 prototype started flight tests in January 2011 and a second example started flying earlier this month. But the US government is adamant that the aircraft will not enter frontline squadron service until much later this decade.
"We expect the J-20 to achieve an effective operational capability no sooner than 2018," Helvey says. "That reflects our judgment and interpretation of how far they are along in doing the research and development and flight testing of the prototypes," he adds.
Operational capability as the DoD defines it means that there should be enough aircraft, weapons and trained air crew to conduct real-world missions, Helvey says.
The DoD also believes that the Chinese have an interest in developing new unmanned aircraft.
"We know that China is interested in developing unmanned air systems, and they have in the past acquired a number of different types of UAVs," Helvey says. "This report doesn't make a net assessment between China's capabilities for unmanned air systems and US capabilities, but that is an area that China is interested in developing."
China has a number of unmanned aerial vehicles including the Israeli-made Israel Aerospace Industries Harpy and a number of domestic types.
Meanwhile, the People's Liberation Army Air Force (PLAAF) is not neglecting its long-range strike capabilities. The country is upgrading its Tupolev Tu-16 Badger-derived Xian B-6 bomber fleet with a new, longer-range variation, which will be armed with new long-range cruise missiles, the report says.
The Chinese are also developing several types of airborne early warning and control system (AWACS) aircraft. These include the Shaanxi Y-8 Moth, based on the Antonov An-12, and the KJ-2000, based on the Ilyushin IL-76 airlifter, the report says.
Meanwhile, China's navy is moving on getting its first aircraft carrier into service. The refurbished Soviet-built ship started sea trials last August, but it not yet operational.
"This aircraft [carrier] could become operationally available to China's navy by the end of this year," Helvey says. "But we expect it'll take several additional years for an air group to achieve a minimal operational capability aboard the aircraft carrier."
The report also indicates that China is probably designing and possibly building in own indigenous carriers.
While China's public statements on its defence budget about $106 billion for 2012, the DoD estimates that the Chinese will actually spend more than $180 billion.
Helvey says the DoD believe that many aspects of China's military modernization actually comes from different spending accounts rather than the main defence budget. Foreign acquisitions such as Russian-built fighters are counted the same way.
"For example, we think that some of their nuclear forces modernisation occurs off budget," he says. "So when you add all of that together, that helps us to develop, I think, a more accurate estimate of what the totality of the military expenditure is."
Chengdu J-20 could enter service by 2018
Seriously ??? to travel 3 times longer, it needs to have 3 times larger fuel tanks? Which planet did you come from?
the terms engine efficiency, drag, sustain military thrust consumption, operational load capacity mean nothing to you?
BronzePlaque
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Heck that is confusing..
By that logic .. an A-380 should outrange the B-777LR by how much???
Audio
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Martian2
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The J-20 and F-22 are both using turbofan engines. The difference in efficiency should not be significant (e.g. it will only be marginal). The higher compression ratio of the F-22 engine will give it a slight edge in efficiency. However, as I have already stated in my "note," the J-20 has canards to provide extra lift that gives it its own fuel-efficiency advantage.
I have already stated the operational load capacity is approximately the same: two side-bay SRAAM and main-bay MRAAM.
Regarding drag, the J-20 is a more aerodynamic plane than the F-22. The F-22 has two large gaps between the engine airducts and the fuselage. Air will flow into the gaps and create drag for the F-22. The J-20 is a later and more modern design. There is no drag-inducing gap. Instead, the J-20 airduct has been seamlessly integrated into the fuselage. Therefore, the superior design and less drag favor the J-20.
Finally, did you read the "note" at the bottom of the post? Does it say the comparison is a rough approximation to illustrate a point? Or are you blind?
A-380 carries almost a thousand passengers (e.g. certified for 853) in economy class. B-777LR has a much lower passenger capacity (e.g. 440 maximum). You can't compare apples to oranges.
In contrast, the J-20 and F-22 both carry one pilot, two side-bay SRAAM, and main-bay MRAAM. Both the J-20 and F-22 are twin-engine fighters. My comparison makes sense.
Your analogy with the A-380 and B-777LR is silly. A-380 has four engines. B-777LR has only two engines.
gambit
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Utter nonsense. This is what happens when we have someone with absolutely no relevant experience going by 'looks' alone and starts making a fool out of himself.
You make the classic mistake of assuming that all aircrafts are constructed with the same internal planform.
WRONG.
One wing can be larger in surface area than another but its internal construction may not allow even the same amount of fuel store, let alone larger. Things such as baffles, spars, mechanical devices for the flight control surfaces, airfoil design specific for the mission type, and so on. Same argument applies to the internal fuselage construction as well.
Wow...
First, there is no definitive argument on what is 'short' versus 'long'. The F-16's combat radius is comparable to the F-22. An aircraft's combat radius is determined by its mission type, which is dictated by something you never heard of until now: DoD Mission Need Statement (MNS).
Something like this...
MISSION NEED STATEMENT (MNS) FOR THEATER MISSILE DEFENSE
Second, here is something you might want to learn from REAL history, not the kind sanitized by the Chinese government propaganda offices...
Note what the Japanese said about focus on ranges instead of survivability: BIG MISTAKE. Essentially speaking.
For the F-22, its mission type is a balanced compromise between these attributes:
- Low radar observability
- Supercruise
- Acceleration
- Maneuverability
- Payload
- Radar detection range
- Airlift support
- Sortie generation rate
- Mean time between maintenance
- Situational awareness capacity
All of the above affects combat radius and survivability. Most fighters grossly sacrifice several attributes in favor of other attributes. Until the F-22, next to nothing attempts have been made to achieve a weighing of these attributes, let alone a balanced approach. How many of the above attributes were sacrificed by the Soviets during the Cold War development? How about most? In other words, the Soviets places so low emphasis on some of them they might as well be eliminated. For the MIG-25 as an example, acceleration and Mach dash grossly overrode everything else.
Awareness (situational) and avoidance of threats increases survivability and being low radar observable coupled with terrain masking greatly increases that survivability WITHIN that combat radius, for example. In other words, any adversary within that combat radius monitored by the F-22 will probably die before he know which direction the missile came from.
Third, if you want to know how large an area is between 400-500 nm operational (or combat) radius, here it is...
So 500 nm is nearly half of continental US (CONUS). In short, nearly half of CONUS is a 'kill box' with near 100% death rate certainty for the F-22's targets.
So when we take in all the attributes as specified by the F-22's MNS, its low-ball combat radius estimate is impressive in light of past fighters with outstanding combat records like the F-15 and F-16. Further, an F-22 can be equipped with external tanks that can/will be jettisoned prior to entering any contested airspace anywhere in the world.
Fine...
...How about all of China's is within the B-2's combat radius. Remember, during the Yugoslavia air campaign, B-2s flew from CONUS to Yugoslavia and back without landing.Now that is more 'Chinese physics' in play. If this is true, then why are airliners, aircrafts whose weight lifting capability is paramount, do not have canards?
If anything, these airlifters should be festooned with various sized wings and winglets EVERYWHERE.Keep this crap over at your playgrounds where other Chinese are gullible enough.
Any real data to go with that...??? Or is this more 'Chinese physics'?
Martian2
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1. J-20 Mighty Dragon 1,243-mile combat radius is indisputably LONGER than F-22 471-mile combat radius. Look up the word "longer" in the dictionary.
2. The F-22's short 471-mile combat radius is a problem, because it means that it must fly from a base in Japan (or Korea). However, China's SRBM, IRBM, and cruise missiles can easily destroy all major air bases on Japan.
3. Using a drop tank on the F-22 would render it less stealthy. By the way genius, how is the F-22 supposed to fly from Shanghai back to Alaska? Is there a drop tank store in mid-air on the way back?
By the way, there is an additional problem. Even if a F-22 flying out of Alaska (or Guam) was able to somehow reach the Chinese coast with drop tanks, it would have little to no loiter time. Basically, the F-22 is useless and cannot engage in aerial combat. It's out of fuel. If it doesn't leave immediately, it will have to crash land. This is a one-way trip.
4. The use of gigantic air-refueling tankers is out of the question. They'll be shot down by Chinese surface-to-air missiles, J-10 air-to-air missiles, or a stealthy J-20 (when inducted).
5. The B-2 is subsonic. It is a slow moving and lumbering aircraft. One of the designers for the B-2's engine has already spilled many of its secrets to China. The B-2 should be detectable with Low-Band radar (see http://www.ausairpower.net/APA-Rus-Low-Band-Radars.html). Chinese interceptor aircraft can be vectored in to intercept the subsonic B-2 sitting duck.
6. Are you a moron? The air gap between the airduct and fuselage on the F-22 leads to a roughly 45-degree angled wall in the back. Are you telling me you don't understand that there is significant drag when high-velocity air (especially when the F-22 is flying supersonic during supercruise) collides with a solid angled wall? You make it sound as if you've never seen a photograph of the rear of the F-22 airduct-fuselage gap.
You irritate me when I have to explain basic physics to you. The momentum of the colliding air molecules is transferred to the F-22. This is called "drag."
2. The F-22's short 471-mile combat radius is a problem, because it means that it must fly from a base in Japan (or Korea). However, China's SRBM, IRBM, and cruise missiles can easily destroy all major air bases on Japan.
3. Using a drop tank on the F-22 would render it less stealthy. By the way genius, how is the F-22 supposed to fly from Shanghai back to Alaska? Is there a drop tank store in mid-air on the way back?
By the way, there is an additional problem. Even if a F-22 flying out of Alaska (or Guam) was able to somehow reach the Chinese coast with drop tanks, it would have little to no loiter time. Basically, the F-22 is useless and cannot engage in aerial combat. It's out of fuel. If it doesn't leave immediately, it will have to crash land. This is a one-way trip.
4. The use of gigantic air-refueling tankers is out of the question. They'll be shot down by Chinese surface-to-air missiles, J-10 air-to-air missiles, or a stealthy J-20 (when inducted).
5. The B-2 is subsonic. It is a slow moving and lumbering aircraft. One of the designers for the B-2's engine has already spilled many of its secrets to China. The B-2 should be detectable with Low-Band radar (see http://www.ausairpower.net/APA-Rus-Low-Band-Radars.html). Chinese interceptor aircraft can be vectored in to intercept the subsonic B-2 sitting duck.
6. Are you a moron? The air gap between the airduct and fuselage on the F-22 leads to a roughly 45-degree angled wall in the back. Are you telling me you don't understand that there is significant drag when high-velocity air (especially when the F-22 is flying supersonic during supercruise) collides with a solid angled wall? You make it sound as if you've never seen a photograph of the rear of the F-22 airduct-fuselage gap.
You irritate me when I have to explain basic physics to you. The momentum of the colliding air molecules is transferred to the F-22. This is called "drag."
gambit
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A longer combat radius does not automatically equal to superiority. The F-15 have a greater combat radius than the F-22 but guess who is going to die first when they meet each other?
China have no experience in such attacks, let alone 'easily'.
When an F-22 is 'less stealthy' it is within someone's radar detection range. Get it? But since you have demonstrated gross ignorance and misunderstanding of 'stealth' to start, I would not be surprised if you do not understand.
By the way, ever heard of in-flight refueling? But of course...You have no military experience in the first place, let alone aviation experience.
This indicate you do not understand how external fuel works at all.
That is funny considering no one have as much experience as we do. So now you are telling everyone that the USAF never -- NEVER -- considered that possibility. I hope the PLAAF thinks like you do.
Look up effective radar horizon and see how useful those radars can be. Not much.
Got any hard data?
Martian2
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1. Low-Band radar can provide information on the general location of a stealth plane. It doesn't have the cm-resolution to guide a missile to its target. However, the meter-resolution Low-Band radar can guide an interceptor to the general location of an enemy stealth plane. Using an AESA-equipped radar, an interceptor should be able to detect an enemy stealth fighter within 20 miles and shoot a missile at it from close range.
2. Try reading the definition of "drag." It perfectly fits supersonic air slamming into the rear wall of the F-22 airduct-fuselage gap. Jesus, I can't believe you're questioning the basic definition of "air resistance." Are you for real?
Do I have any hard data on the exact amount of drag on the F-22 from the airduct-fuselage gap? I don't know. Have you heard the F-22 is classified?
Drag (physics) - Wikipedia, the free encyclopedia
"In fluid dynamics, drag (sometimes called air resistance or fluid resistance) refers to forces which act on a solid object in the direction of the relative fluid flow velocity.[1][2][3][4] Unlike other resistive forces such as dry friction, which is nearly independent of velocity, drag forces depend on velocity.[5]"
2. Try reading the definition of "drag." It perfectly fits supersonic air slamming into the rear wall of the F-22 airduct-fuselage gap. Jesus, I can't believe you're questioning the basic definition of "air resistance." Are you for real?
Do I have any hard data on the exact amount of drag on the F-22 from the airduct-fuselage gap? I don't know. Have you heard the F-22 is classified?
Drag (physics) - Wikipedia, the free encyclopedia
"In fluid dynamics, drag (sometimes called air resistance or fluid resistance) refers to forces which act on a solid object in the direction of the relative fluid flow velocity.[1][2][3][4] Unlike other resistive forces such as dry friction, which is nearly independent of velocity, drag forces depend on velocity.[5]"
gambit
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Meters lengths freqs systems are ground based, therefore their EFFECTIVE detection range are line-of-sight limited from the ground, not from being airborne.
That is not the issue. Your argument is that the J-20 is 'more aerodynamics' than the F-22 based solely upon the diverter assembly.
Provide hard data for that argument.
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