Chinese J-20 a powerful competitor to American F-22 & Russian T-50

[Martian2]

Wrong...Diverterless Supersonic Inlet (DSI) has nothing to do with RCS reduction. Do not mistake the 'diverter' word to mean for impinging radar signals. It is meant for boundary air upon a surface.

Aviation Week says that you are the one that is wrong.

J-20's Stealth Signature Poses Interesting Unknowns

"The diverterless supersonic inlet avoids a signature problem caused by a conventional boundary layer diverter plate – the F-22 has a conventional inlet, which is likely to require extensive radar absorbent material (RAM) treatment."

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As I understand it, if a supersonic-capable aircraft lacks DSI then it needs "heavy mechanical systems" to control airflow into the air inlet. The "heavy mechanical systems" and "many moving parts" require heavy RAM coating to minimize their radar reflection.

http://en.wikipedia.org/wiki/User:Sniperz11/Diverterless_Supersonic_Inlet

"The DSI bump functions as a compression surface and creates a pressure distribution that prevents the majority of the boundary layer air from entering the inlet at speeds up to Mach 2. In essence, the DSI does away with complex and heavy mechanical systems.

The DSI concept was introduced into the JAST/JSF program as a trade study item in mid-1994. It was compared with a traditional "caret" style inlet. The trade studies involved additional CFD, testing, and weight and cost analyses. The new inlet earned its way into the JSF design after proving to be thirty percent lighter and showing lower production and maintenance costs over traditional inlets while still meeting all performance requirements.

Diverterless Inlet The F-35's diverterless inlet lightens the overall weight of the aircraft. Traditional aircraft inlets were comprised of many moving parts and are much heavier than newer diverterless inlets. The diverterless inlet also eliminates all moving parts.[2]"

 

[cross1993]

USA is the only superpower. The US economy is still three times as large as China’s. The US is still the world’s largest manufacturing base. The US dollar still dominates world’s financial affairs by far.
China's GDP per capita is still miles behind its European, American, and Japanese counterparts. China just wants to develop itself to better prosperity for its people, never mind that “superpower” nonsense talk.

 

[ChineseTiger1986]

USA is the only superpower. The US economy is still three times as large as China’s. The US is still the world’s largest manufacturing base. The US dollar still dominates world’s financial affairs by far.
China's GDP per capita is still miles behind its European, American, and Japanese counterparts. China just wants to develop itself to better prosperity for its people, never mind that “superpower” nonsense talk.

US' GDP is less than 2.5 right now. The problem is that they still have much more influence than us.

 

[gambit]

Aviation Weeks says that you are the one that is wrong.

J-20's Stealth Signature Poses Interesting Unknowns

"The diverterless supersonic inlet avoids a signature problem caused by a conventional boundary layer diverter plate – the F-22 has a conventional inlet, which is likely to require extensive radar absorbent material (RAM) treatment."

----------

As I understand it, if a supersonic-capable aircraft lacks DSI then it needs "heavy mechanical systems" to control airflow into the air inlet. The "heavy mechanical systems" and "many moving parts" require heavy RAM coating to minimize their radar reflection.

User:Sniperz11/Diverterless Supersonic Inlet - Wikipedia, the free encyclopedia

"The DSI bump functions as a compression surface and creates a pressure distribution that prevents the majority of the boundary layer air from entering the inlet at speeds up to Mach 2. In essence, the DSI does away with complex and heavy mechanical systems.

The DSI concept was introduced into the JAST/JSF program as a trade study item in mid-1994. It was compared with a traditional "caret" style inlet. The trade studies involved additional CFD, testing, and weight and cost analyses. The new inlet earned its way into the JSF design after proving to be thirty percent lighter and showing lower production and maintenance costs over traditional inlets while still meeting all performance requirements.

Diverterless Inlet The F-35's diverterless inlet lightens the overall weight of the aircraft. Traditional aircraft inlets were comprised of many moving parts and are much heavier than newer diverterless inlets. The diverterless inlet also eliminates all moving parts.[2]"

Your lack of understanding of the TRUE intention of a diverterless supesonic inlet (DSI) is evident.

Try this for starter...

http://www.defence.pk/forums/440120-post1277.html
http://www.defence.pk/forums/1383607-post785.html

If a DSI helps in RCS reduction, it is an INCIDENTAL benefit, not because sometime back, somebody thought up on how to reduce frontal RCS via DSI...

 

[All-Green]

Your lack of understanding of the TRUE intention of a diverterless supesonic inlet (DSI) is evident.

Try this for starter...

http://www.defence.pk/forums/440120-post1277.html
http://www.defence.pk/forums/1383607-post785.html

If a DSI helps in RCS reduction, it is an INCIDENTAL benefit, not because sometime back, somebody thought up on how to reduce frontal RCS via DSI...

Dear Gambit,

You are spot on that DSI was not developed for stealth purpose, its driver was parity in flight performance without the complex systems (and additional weight of such systems) leading to lower manufacturing cost and operational cost/headache.
So if a newbie thinks that DSI development was driven from stealth perspective he could not be more wrong.

However if there is now a recognized benefit of DSI in reducing the RCS, then it would perhaps be misleading to claim that DSI has nothing to with RCS.
I think, this is what Martian2 understood from your previous post and was trying to clarify.

Do you think there is a reduction in RCS due to DSI or not?

 

[mughaljee]

how much time this will take to appear in full action ?

 

[ChineseTiger1986]

how much time this will take to appear in full action ?

2015 is very likely, and don't be surprised that PLAAF even pulls out this bird earlier.

 

[Dragon Emperor]

US' GDP is less than 2.5 right now. The problem is that they still have much more influence than us.

The reason why US has more influence than China, is because USA has just TOO MANY ALLIES-South Korea, Japan, EU, Arabian countries, etc. What all-weather ally does China have? Pakistan(Not as economically powerful as Japan or South K-no offense to PK members here just stating facts), Russia(Russia is not China's ally, just a neighbor with average relation), SCO member states(unreliable and not a match for NATO).

So China needs more allies, but while searching for allies, China must militarize more to defend country.

 

[gambit]

Dear Gambit,

You are spot on that DSI was not developed for stealth purpose, its driver was parity in flight performance without the complex systems (and additional weight of such systems) leading to lower manufacturing cost and operational cost/headache.
So if a newbie thinks that DSI development was driven from stealth perspective he could not be more wrong.

However if there is now a recognized benefit of DSI in reducing the RCS, then it would perhaps be misleading to claim that DSI has nothing to with RCS.
I think, this is what Martian2 understood from your previous post and was trying to clarify.

Do you think there is a reduction in RCS due to DSI or not?

Look at the issue this way...In RCS reduction, we know the single vertical stabilator is a great sin, so we move to the twin canted design to reduce side-on RCS. But this is applicable to all speeds. If we wanted to make our 'stealth' fighter to be subsonic only, then the DSI feature is irrelevant. So I do not think that it is misleading in any way to say that DSI as nothing to do with RCS. The design is solely FOR inlet air control with the 'bump' being nowhere as great a contributor to RCS as other movable methods of inlet air control. You have to look at things as how each item is a contributor to RCS, if it is possible to remove said contributor, and if the aircraft can still perform at the same level after said removal. The guy just never had the complete understanding of it so he just grabbed onto the nearest general commentary out there.

 

[below_freezing]

The reason why US has more influence than China, is because USA has just TOO MANY ALLIES-South Korea, Japan, EU, Arabian countries, etc. What all-weather ally does China have? Pakistan(Not as economically powerful as Japan or South K-no offense to PK members here just stating facts), Russia(Russia is not China's ally, just a neighbor with average relation), SCO member states(unreliable and not a match for NATO).

So China needs more allies, but while searching for allies, China must militarize more to defend country.

You mean "allies". Japan is just waiting to bite the US back in the neck when it is freed from its chains. South Korea on the other hand truly loves the US. The arabian countries are all feudal monarchies who actually hate the US but their dictators are keeping them down. If we can make it clear to their apelike leaders that their future lies with us, they'll dump the US in a second. As soon as the USD loses its dominance, which is strongly linked with US military strength and its control over Middle Eastern dictators, it will fall like a house of cards.

 

[NmHqh2JbVo]

You mean "allies". Japan is just waiting to bite the US back in the neck when it is freed from its chains. South Korea on the other hand truly loves the US. The arabian countries are all feudal monarchies who actually hate the US but their dictators are keeping them down. If we can make it clear to their apelike leaders that their future lies with us, they'll dump the US in a second. As soon as the USD loses its dominance, which is strongly linked with US military strength and its control over Middle Eastern dictators, it will fall like a house of cards.

"South Korea on the other hand truly loves the US", especially after 300 million of Samsung's money was "robbed" to help their little adventure in Iraq, Oh, I think Toyota helped a little bit as well, you know, those naughty brake peddle problems.

 

[revu]

Look at the issue this way...In RCS reduction, we know the single vertical stabilator is a great sin, so we move to the twin canted design to reduce side-on RCS. But this is applicable to all speeds. If we wanted to make our 'stealth' fighter to be subsonic only, then the DSI feature is irrelevant. So I do not think that it is misleading in any way to say that DSI as nothing to do with RCS. The design is solely FOR inlet air control with the 'bump' being nowhere as great a contributor to RCS as other movable methods of inlet air control. You have to look at things as how each item is a contributor to RCS, if it is possible to remove said contributor, and if the aircraft can still perform at the same level after said removal. The guy just never had the complete understanding of it so he just grabbed onto the nearest general commentary out there.

DSI are designed for air control, this i'm agree with gambit. But in J-20 case i think DSI also help reduce the frontal RCS of the plane, because that bump can be used to hide the engine blade, it help reduce the usage of RAM like in F-22 inlet. So DSI function is for air control, but if it designed cleverly it also help to reduce RCS, i think there is no such INCIDENTAL in designing a stealth plane.

 

[cross1993]

2015 to 2017

 

[monitor]

Chinese fighter jet rewrites power in region, says critic
Dan Oakes DEFENCE CORRESPONDENT
January 15, 2011


THE shock unveiling of a Chinese stealth fighter plane has changed the power balance in Asia and means Australia must rethink its regional strategy, an Australian analyst has said.

Peter Goon, a vehement critic of the F-35 joint strike fighter that Australia has committed to buying from the United States, says the Chinese J-20 is far superior to the American fighter and we must immediately adapt to the new status quo.

The Chinese tested the J-20 for the first time last week, on the day that the US Defence Secretary, Robert Gates, arrived in Beijing for defence-related talks. Although the Chinese said the timing was coincidental, Mr Gates expressed concerns about the military's motives.
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A Lowy Institute analyst, Rory Medcalf, a recent visitor to Beijing, said it was possible that the military did not signal the testing as a way of expressing displeasure at Mr Gates's visit.

Mr Goon, co-founder of the Air Power Australia think-tank, said the US and its allies had been ''caught flat-footed'' by the J-20's maiden appearance.

The J-20 has been described by some analysts overseas as ''unimpressive'' and a ''mish-mash of Soviet and American design features''. But Mr Goon said it was clear from the images of the plane and other material that it is far superior to the JSF, and even to America's top-of-the-range F-22 ''Raptor'' jet.

''It is basically a lot more stealthy than the JSF, will fly faster and higher, be more agile and because it's a much bigger aircraft it can carry more weapons,'' he said.

''This thing has been designed to compete with and defeat the F-22. They haven't even bothered with the JSF, and why would you?''

Mr Goon said the J-20 had been designed to advance China's ''second island chain'' strategy, which promotes the protection of Chinese trade routes within an area bordered in the east by Pacific islands such as the Marianas, Guam and the Caroline Islands, all the way to the eastern end of the Indonesian archipelago. In other words, most of south-east Asia.

One of the priorities in the federal government's 2009 Defence white paper was the need for Australia to achieve and maintain air combat superiority in the region.

''If Defence does not rethink in a timely, objective and coherent way their current plans we should take them out, put them in the stocks and pillory them,'' Mr Goon said.

''If they don't now redress the situation that's obvious to everyone else as a result of the J-20 and the T-50, then they're being delinquent in their responsibilities.''

Air Power Australia has been a loud critic of the government's decision to order 100 of the joint strike fighters for up to $16 billion, on the basis of cost and capability. The JSF project has been bedevilled by cost blowouts, technical problems and schedule overruns.

Following a recent Pentagon review of the troubled project, Mr Gates threatened to cancel the US Marines version of the fighter within two years unless the lead contractor, Lockheed Martin, ironed out problems with its structure and propulsion systems and lack of reliability.

The US Debt Commission has also recommended the Marines' F-35 be axed. Production on the F-22 jet was stopped by Mr Gates last year because it was too expensive.

 

[Transgress]

There are a number of ways to shield the intake compressors, the most talked about is radar blocker, the F-117 had radar blockers and many other aircraft have or had them, other methods involve curved inlets, ect. The important thing is the designers know about this and will not just leave the intake compressors exposed. Even more interesting is that Sukhoi is currently studying flat nozzles, this just shows that the final version will likely be much different than the aerodynamics test bed we see flying.

In any case your argument about radar blockers is plainly wrong considering the F-15 SE has the same frontal RCS as the F-35 and even the F-117 used radar blockers. If i was you i would wory more about the J-20's canards instead telling everyone about how poor the pak-fa is, if you want to know why they are a problem visit the J-20 thread thread for a real explanation, since you think canards do nothing for stealth.

I'm no aerospace expert, but imho, the F-117 was a heavy bomber, using heavy RAM and grills as radar blockers, which affected intake, but again, it was a stealth bomber, with stealth being its main defense and not needing to do too many maneuvers. The F-15, on the other hand, is a fighter, but how far can radar blockers go?(BTW one F-15 SE is aimed at being 100m, same estimate as PAK-FA) Can you please show us a source of the claim that the F-15SE has the same frontal RCS as a F-35. I'm kind of skeptical of that claim, how many other fighters use radar blockers?