Russia refuses to sell Nimitz Aircraft Carrier and space shuttle to China

[Manticore]

Stick to the topic.No insults .Every thread in china def ends up derailed by the same members - enough is enough

 

[antonius123]

Please...I am an old hand at this. Am old enough to live and work in the pre-Internet (pre-historic) era. I recognize a feeble attempt when I see one.

But never be prejudiced on other people's argument

Then why bother to make them curves at all? The B-2's missions are not as limited as you think. Its designers must consider customer's demands and its final shape reflect (pun intended) those demands.

I have explained the continuous curvature is in order to minimize radar reflected way back to the sender.

How do you assume that?
The main function of B-2 is to penetrate enemy's territory and drop bomb; what else function do you mean?

Technically, you are not wrong. But equally technically, your understanding of 'stealth' or more accurately 'low radar observability' is inadequate and filled with lower levels of misconceptions.

Really? but you haven't show anything wrong with my argument.

What a curious statement this 'will not be good'. Why are these structures 'not good'? A structure is a potential radiator whether the structure is a part of the canopy or an engine. Everything is a potential radiator, hence, a 'contributor' to the final RCS value. Apparently everything I said in post 202 did not compute. Sharp angles? So what? Are they angled to deny the seeker their contributorship of 'received' power? If yes, then why are they 'not good'? Metal framed canopy? The F-117 have it. If anything, the cockpit well is even more problematic than the canopy -- resonance. You just further confirmed to me that the basic principle of threshold is incompatible with 'Chinese physics'.

Nobody deny that everything is potential radiator/reflector, but of course not everything has the same degree.

I said the sharp angle should be avoided to minimize rcs. Not on the other way round.

Then who said metal canopy of F-117 is perfect? besides The F-117 employs flat window panels and radar-absorbing treatments on the cockpit windows.

 

[500]

Su-35 is nice 4++ gen fighter. It has powerful engines with TVC, fuselage with improved aerodynamicsa and increased internal fuel tanks, long range radar and IRST. Chinese engineers would very like to research it. But buying 48 jets is way to high price for checking 4++ fighter.

I guess what happened is that China asked to buy a small batch of Su-35 and Russia in return offered to sell 48, but China refused.

 

[ChineseTiger1986]

Su-35 is nice 4++ gen fighter. It has powerful engines with TVC, fuselage with improved aerodynamicsa and increased internal fuel tanks, long range radar and IRST. Chinese engineers would very like to research it. But buying 48 jets is way to high price for checking 4++ fighter.

I guess what happened is that China asked to buy a small batch of Su-35 and Russia in return offered to sell 48, but China refused.

According to the ministry of defence, China never sought the negociation about Su-35.

This news was purely hyped up by the big mouth Russian media.

 

[Tesla1000]

Last time i checked Nimitz class carrier is a US made weapon.Is this a troll thread ?

 

[Aramsogo]

@ptldM3

China fought Japan from 1937 (some say much earlier)
US since 1941 Pearl Harbor
Russia declares War on Japan AFTER Hiroshima
Before that, Russia got azz kicked in Russo Japanese War.

no, Russia did not help China with Japan

 

[FairAndUnbiased]

@ptldM3

China fought Japan from 1937 (some say much earlier)
US since 1941 Pearl Harbor
Russia declares War on Japan AFTER Hiroshima
Before that, Russia got azz kicked in Russo Japanese War.

no, Russia did not help China with Japan

Russia crushed Japan in Mongolia though. Its more like they were distracted a bit by Hitler being at the gates of Moscow and all.

 

[gambit]

But never be prejudiced on other people's argument

When I have the laws of nature on my side, you bet am going to be prejudicial.

I have explained the continuous curvature is in order to minimize radar reflected way back to the sender.

How do you assume that?
The main function of B-2 is to penetrate enemy's territory and drop bomb; what else function do you mean?

Are you speaking from extensive military experience? If not, then do not impose your limited understanding on US. The B-52's original mission was to deliver bombs, then became an airborne cruise missile launcher, now it is planned to be a long range, long duration, and high powered EW platform. Powerful enough to blank out any major cosmopolitan city in the world.

For the B-2, do not assume that its flight condition is limited to high altitude where its cluttered topside is shielded by the long wingspan. If that is true, then we would not have bothered to extensively shaped the entire aircraft as is. The customer demanded that the aircraft be as low radar observable as possible, even if the seeker is overhead, and that mean the B-2 may have very low altitude missions.

Really? but you haven't show anything wrong with my argument.

Quite often being so woefully inadequate in knowledge and understanding is just as bad as being wrong.

Nobody deny that everything is potential radiator/reflector, but of course not everything has the same degree.

Do tell me something I do not know. See post 183...

http://www.defence.pk/forums/chines...rrier-space-shuttle-china-13.html#post2718596

...With that illustration of the airliner as how a radar system would see it.

I said the sharp angle should be avoided to minimize rcs. Not on the other way round.

This is where you are wrong. The radar cross section (RCS) value is based upon RECEIVED power, some would call it 'power returned' or 'echo returned'. But no matter which version, it is whatever the radar system will received that will enable it to calculate the targets' RCS. What this mean is that there are only two main complex structures that will have a detrimental effect on low radar obversability:

- The flat plate that is facing directly the seeker.

- The 90deg corner reflector.

Everything else, from 'sharp angle' to curvatures, if they are shaped in such a way that each will have negative effect on received power, said complex structure is allowed.

Once again, you proved my point completely, that if anyone swallowed 'Chinese physics' as propounded by some here, the ideas of received power and threshold, crucial in radar detection and 'stealth', became as alien to them as air is to fishes.

Then who said metal canopy of F-117 is perfect?

Not me. But my point was that the F-117's canopy has far more 'sharp angles' than most realized. So go back to my post 183 and study it again.

besides The F-117 employs flat window panels and radar-absorbing treatments on the cockpit windows.

Do tell me something I do not know.

 

[ptldM3]

@ptldM3

China fought Japan from 1937 (some say much earlier)
US since 1941 Pearl Harbor
Russia declares War on Japan AFTER Hiroshima
Before that, Russia got azz kicked in Russo Japanese War.

no, Russia did not help China with Japan

Researching history couldn't hurt before making such claims in public. When Russia declared war on Japan they sent over 1.5 millions men and thousands of pieces of machinery to face over 1 million Japanese men. In one campaign the Soviet Union annihilated the Japanese military.. You can deny all you want but the fact don't lie.

 

[Sashan]

Researching history couldn't hurt before making such claims in public. When Russia declared war on Japan they sent over 1.5 millions men and thousands of pieces of machinery to face over 1 million Japanese men. In one campaign the Soviet Union annihilated the Japanese military.. You can deny all you want but the fact don't lie.

Russian war with Japan in Manchuria is one of the largest in the 2nd world war.

 

[ptldM3]

I have explained that those rcs contributors is hidden by its wing, therefore radar wave coming from ground radar doesnt reach all of them (canopy metal, round shape, etc).

So now you do acknowledge that an aircraft does not need to be inverted or banked for EM energy to ’reach’ its upper fuselage.

I have also explained that B-2 bomber doesnt bank and get inverted like air fighter.

Prove it. Without banking how does it turn. Even commercial airliners bank. Aircraft on combat missions don’t simply fly in a strait line, they will often circle or bank into their targets. Combat missions often have aircraft fly around high threat areas, so the flight path of an aircraft is never linear.

if wing blended body of B-2 is already sufficient to cover the canopies etc, it doesnt need any diffracter; besides what kind diffracter you mean applied on B-2 canopy etc?

Not sufficient when the aircraft banks, and yes the B-2 has to bank in order to turn. And did I just read your sentence correctly? The B-2 does not need any diffraction?

Which kind of airbrake you mean?

Isnt airbrake folded in normal flying?

Yes it’s folded but it still has a junction or gap, so again why is an airbrake, which actually has a four sided junction, not a problem but for reasons unknown to me a two piece canopy with one junction is a problem.

I dont say side should be neglected. I said if we want to know whether the fuselage shape is really round or not we cant see from side angle, but from front angle.

So why can’t we see if an aircraft is curved from a side? What makes the front special?

Besides, why u think B-2 has RCS problem from rear or side? B-2 only has RCS problem from above, or if it get inverted which normally it doesnt.

Post a source for this, even the F-22 can not be locked onto from the rear despite its visible engines.

B-2 banking is not much like F-22 airfighter, and when penetrating enemy territory I dont think B-2 will do considerable banking.

So by your logic should the B-2 be picked up on radar every time it has to bank? Remember the YF-23 has a smaller RCS than the YF-22 and it has a two piece canopy it also has the same ‘tall’ fuselage as the pak-fa and the top half of the fuselage (where the engines are) is similar to the bottom half of the pak-fa, its engines were also exposed. And remember RCS is not based off of one angle.

Besides as i said, I dont see round top fusselage of B-2.

If this isn’t round that I don’t know what is:



http://robotics.eecs.berkeley.edu/~pister/DSSG/dssg6-2/b2front.jpg

Of course for F-22 / F-35 since the fighter will bank and get inverted so much they shape of top side should be much considered for very low rcs.

Yet that is contradicting your other statement. How is a bubble canopy, two vertical stabilizers as well as curvature in the fuselage not a problem for those aircraft but you claim it is a problem for the pak-fa.

Yes you are right.

But what kind of method that PAKFA applied to minimize RCS, if not continuous curvature or the F-117 method?

It uses more curvature than anything else although it applies faceting particularly inside the intake and in front of the actual intake.

Of course it banks, as you see in the picture it bank only a bit, not much like airfighter, therefore should be not much issue for penetration and bombing mission.

That bank is hard enough to expose its cockpit and curvature so how is it not an issue?

You are wrong, there is not much corner on F-117 surface, as the facet of the surface create very wide angle (above 180 degree) just like diamonds. This faceted wide angle as the matter of fact scatter radar wave, then minimize the radar wave bounced back to the origin.

No, it is you who are wrong, and not only wrong but ignorant of the subject as well. Firstly, did you just say that there are not much corners on the F-117? For your sake I hope that was a typo. The entire design of the F-117 is made of corners, we call these corners faceting, every faceted corners in joined, where those joints meet is where those sharp corners are seen, unless you are suggesting that the F-117 sharp edges are an optical elusion?

On the other way round there are many corner / sharp angle on PAKFA that potential to send back radar wave adequately to its origin.

Your so full of it that your bias hatred for the pak-fa is becoming more delusional and desperate by each post. Your claim goes against the entire principle of stealth. The point of stealth is to have corners/sharp angles. Why do you think stealth aircraft have sharp corners on their wings? Why did you think the B-2 had serration on its wings? The entire F-117 was made of sharp corners where each faceted surface inner connected with the next to create sharp edges/corners. Conventional aircraft wings, nose, ect designs can create diffraction off of their corner surfaces because they do not adhere to stealth principles. Notice all of the corners on the pak-fa’s wing, notice the sharp tail boom, notice that faceted angles around the intake, what do you think those are for, to look pretty?

There is one general rule in designing stealth aircraft and that is to never have any structures that are perpendicular in relation to the front of the aircraft, by this I mostly mean wings. Conventional wings that are perpendicular will send back EM energy because there is nowhere to harness and redirect that energy and thus the many parts of the wing whether its flaps, or the design or lack there of in corners scatters EM energy. When you see serrated or trapezoid wings they utilize sharp angles to direct EM energy or built up off those sharp corners, notice the LERX or leading edge extensions on both the F-22 and pak-fa those sharp angles are not coincidental. Where you are mistaken and obviously bias is that you believe that the Russians are too stupid to consider so called ‘corners’ when the design of the pak-fa strongly adheres to general principles in stealth design.

Only if the radar wave coming from infront or upward, not from downward.

If the aircraft is far enough and or low enough a ground based radar can ‘eliminate’ any part of the aircraft.



.

Thinner body is not the only one factor affecting the surface size; the contour of the body counts.

PAKFa body with its contour create big surface area, and more over ANGLE that potential to reflect radar wave back to the sender.

By that logic than the J-20’s contoured DSI also creates a large surface area. And by your logic the J-20’s tail fins act as a handicap.

It is not identical at all.

As you said the gap of pakfa is receded, I have explain that this receded one on pakfa as a matter fact will make the angle formed by it's airduct and fuselage exposed to radar wave. This is not applied on F-22, as you see on bellow picture the angle between airduct and fuselage is well hidden from radar wave.

What are you talking about? Both aircraft have an identical ‘gap’ between the fuselage and intake. The pak-fa just has less of a gap since very little of the intake actually runs down the fuselage.



Take a good look at that ‘gap’:


http://paralay.com/su50/IMG_4573.JPG


Now tell everyone what kind of ‘stealth’ rule the pak-fa is violating.

the curvature on pakfa is less continuous then create many angles.

You need angles. The F-117 lived off of angles.

Of course the bigger RCS of the top side F-22 will be exposed to ground radar when it get inverted. But why F-22 need to get inverted during its penetration into enemy territory?

I’m not even talking about ground radar, the F-22 has been in various exercise both in the US and against NATO countries, in dog fights, apposing aircraft can not achieve a lock on the F-22 whether they are directly behind it or above it. No radar lock means that the aircraft is doing what is was made to do, more importantly it proves curved surfaces can evade radar.

F-117 surface distract radar wave reflection away from the sender.

I don’t see PAKFA fuselage surface nor F-22/F-35 as you mentioned above - applied the same method as those of F-117.

Explain me why you think so?

The F-117 used faceting, this is still used in all aircraft you mentioned but not exclusively. The problem with the F-117 was that its faceting came with a price, aerodynamically it was not very efficient.

Russian war with Japan in Manchuria is one of the largest in the 2nd world war.

Its one of the largest battles ever, that left the Japanese military in Manchuria shattered.

 

[antonius123]

So now you do acknowledge that an aircraft does not need to be inverted or banked for EM energy to ’reach’ its upper fuselage.

Only if the radar wave coming from upward or frontward, not downward.

I have explained you about the S duct shape to hide fanblade, it will be a waste if radar wave could reach the blade at the end.

Prove it. Without banking how does it turn. Even commercial airliners bank. Aircraft on combat missions don’t simply fly in a strait line, they will often circle or bank into their targets. Combat missions often have aircraft fly around high threat areas, so the flight path of an aircraft is never linear.

I am saying not bank like airfighter (which is steep bank) during the its mission (penetrating & bombing); I am not saying B-2 never or doesnt need to bank at all.

Not sufficient when the aircraft banks, and yes the B-2 has to bank in order to turn. And did I just read your sentence correctly? The B-2 does not need any diffraction?

See my sentence carefully. I said in the top side of B-2, doesnt need much like bottom side as the top side is covered by the wing.

Yes it’s folded but it still has a junction or gap, so again why is an airbrake, which actually has a four sided junction, not a problem but for reasons unknown to me a two piece canopy with one junction is a problem.

I dont see any gap when its folded, why do CAC should make any gap around the folded airbrake? doesnt make sense. But even if there is, it is minor.

So why can’t we see if an aircraft is curved from a side? What makes the front special?

The curve doesnt always mean really round, simple logic. Thats why i recommend you to see from front side, If you see from the front side, it is not really that round

Post a source for this, even the F-22 can not be locked onto from the rear despite its visible engines.

Well you need to post a source saying B-2 has problem with RCS from side and rear first, because I am referring my statement to yours. I said B-2 fuselage is not round and hence doesn't bounch back radar wave to the origin when it get inverted

So by your logic should the B-2 be picked up on radar every time it has to bank? Remember the YF-23 has a smaller RCS than the YF-22 and it has a two piece canopy it also has the same ‘tall’ fuselage as the pak-fa and the top half of the fuselage (where the engines are) is similar to the bottom half of the pak-fa, its engines were also exposed. And remember RCS is not based off of one angle.

Thats your false deduction / logic. How enemy will know B-2 banks?

Also I am saying B-2 doesnt bank steeply like Airfighter when it is on mission. Doesnt mean not bank at all. B-2 is not aimed for doght fight. The 2 piece of canopy may be the drawback of YF23 compared to F-22, on the top of the better shape of YF-23 in term of rcs reduction.

Post prove that YF23 engine blade is exposed.

If this isn’t round that I don’t know what is:
http://robotics.eecs.berkeley.edu/~pister/DSSG/dssg6-2/b2front.jpg

It is rather like curve than round.

Also you should see the the fuselage and the wing is blended that doesnt create any corner or sharp angle, you cant look it from that angle on the picture. Therefore even if it get inverted, the fuselage wont be the problem except the metal canopy frame and air intake/fanblade.

Besides as I said, the top fuselage is well covered by wing from ground radar even when B-2 bank the air intake is still well hidden from ground radar, as long as not steep bank.

Yet that is contradicting your other statement. How is a bubble canopy, two vertical stabilizers as well as curvature in the fuselage not a problem for those aircraft but you claim it is a problem for the pak-fa.

It contradict your own statement, not mine.

There is no problem with bubble canopy in term of considerable RCS contribution.
The two vertical stabilizer of F-22 is designed not perpendicular to the radar wave from ground and doesnt create corner/sharp angle with its body. The curvature of the F-22 is continous even on the top fuselage; so why you think there is RCS problem on the top of F-22?

It uses more curvature than anything else although it applies faceting particularly inside the intake and in front of the actual intake.

As I said, there is many discontinuous curvatures on Pakfa that create sharp angle. You could see some sharp angle on it, and you could see the gap that potential to bounce back radar wave.

That bank is hard enough to expose its cockpit and curvature so how is it not an issue?

Really?? why should B-2 bank that hard enough in the mission? Bomber doesnt need to take hard maneuver

Besides as I said, the curvature of B-2 even on the top side is continuous, its good for RCS reduction.

As I said framed canopy may be the weakness of B-2, but it is not major; thats why B-2 RCS is bigger.

No, it is you who are wrong, and not only wrong but ignorant of the subject as well. Firstly, did you just say that there are not much corners on the F-117? For your sake I hope that was a typo. The entire design of the F-117 is made of corners, we call these corners faceting, every faceted corners in joined, where those joints meet is where those sharp corners are seen, unless you are suggesting that the F-117 sharp edges are an optical elusion?

It is not my typo; please tell me how many corners especially sharp corner (nearly perpendicular/90 degree) that F-117 has?? and how many Pakfa has?

Besides as I said, the faceted F-117 create wide angle; the corner on pakfa angle is wide not sharp like those found in PAKFA. I have explained this to you, so it is you that are ignorant.

Besides we are comparing the top of F-117 fuselage vs bottom fusselage of Pakfa. Of course the bottom side for a pakfa fighter is exposed to radar ground than top side bomber F-117

Your so full of it that your bias hatred for the pak-fa is becoming more delusional and desperate by each post. Your claim goes against the entire principle of stealth. The point of stealth is to have corners/sharp angles. Why do you think stealth aircraft have sharp corners on their wings? Why did you think the B-2 had serration on its wings? The entire F-117 was made of sharp corners where each faceted surface inner connected with the next to create sharp edges/corners. Conventional aircraft wings, nose, ect designs can create diffraction off of their corner surfaces because they do not adhere to stealth principles. Notice all of the corners on the pak-fa’s wing, notice the sharp tail boom, notice that faceted angles around the intake, what do you think those are for, to look pretty?

Before you indict me as bias hatred etc, you must prove your claim above where as matter of fact your claims are only repetition and has been countered by me due to your capability to understand other explanation carefully.

Show me any single sharp corner of F-117! as you said entirely F-117 is made of sharp corners is a prove of your ignorance

Besides your explanation above indicates you do not really understand the stealth as much as you think as you said corner will defract radar wave is wrong in the stealth world.

There is one general rule in designing stealth aircraft and that is to never have any structures that are perpendicular in relation to the front of the aircraft, by this I mostly mean wings. Conventional wings that are perpendicular will send back EM energy because there is nowhere to harness and redirect that energy and thus the many parts of the wing whether its flaps, or the design or lack there of in corners scatters EM energy. When you see serrated or trapezoid wings they utilize sharp angles to direct EM energy or built up off those sharp corners, notice the LERX or leading edge extensions on both the F-22 and pak-fa those sharp angles are not coincidental. Where you are mistaken and obviously bias is that you believe that the Russians are too stupid to consider so called ‘corners’ when the design of the pak-fa strongly adheres to general principles in stealth design.

I am not bias, it is you that are bias that missunderstand my points and bringing unproven claims.

You are obviously mixed saw tooth with sharp corner, it is not the same

I am not saying Russians are too stupid for this sharp corners, it is your own assumption - or your bias assumption.

The continuous curvature design is highly complicated, requires super computation and deep research, and maybe Russia has limited fund for this kind of research. Please refer to the article I attach bellow.

I give you one good article regarding stealth and perpendicular angle for your study:
Aerospaceweb.org | Ask Us - Stealth Technology

If the aircraft is far enough and or low enough a ground based radar can ‘eliminate’ any part of the aircraft.

B-2 fly very high in its mission, and remember the round shape of earth.

By that logic than the J-20’s contoured DSI also creates a large surface area. And by your logic the J-20’s tail fins act as a handicap.

You are wrong, DSI doesn't create large surface area at the outside that exposed to the radar wave. How do you conclude that?

There is nothing wrong with J-20 tailpin, it doesnt create sharp corner with the body as you expect. Show me the sharp corner of it if you do not agree.

What are you talking about? Both aircraft have an identical ‘gap’ between the fuselage and intake. The pak-fa just has less of a gap since very little of the intake actually runs down the fuselage.



Take a good look at that ‘gap’:


http://paralay.com/su50/IMG_4573.JPG

What do you mean identical?? are you blind or something??

The gap of F-22 is glaringly extremely narrow and doesn't expose its corner, it is totally different with Pakfa with very wide distance between its 2 airintake, i have shown you that of F-22; how could you claim identical

Now tell everyone what kind of ‘stealth’ rule the pak-fa is violating.

I have told you many times, that obviously you ignore or fail to understand.

The sharper corner found on PAKFA violate the radar low observability rule as its potential to bounce back radar wave back to origin

You need angles. The F-117 lived off of angles.

I told you the angles on F-117 are wide, not sharp like those on PAKFA.
What make you difficult to understand this?

I’m not even talking about ground radar, the F-22 has been in various exercise both in the US and against NATO countries, in dog fights, apposing aircraft can not achieve a lock on the F-22 whether they are directly behind it or above it. No radar lock means that the aircraft is doing what is was made to do, more importantly it proves curved surfaces can evade radar.

Some part of PAKFA violate continuous curvature applied on F-22

The F-117 used faceting, this is still used in all aircraft you mentioned but not exclusively. The problem with the F-117 was that its faceting came with a price, aerodynamically it was not very efficient.

If Pakfa use facetting, it must be not entirely because facet wont create sharp corner. As you see facet diamond no corner at all. F-117 still have corners but not sharp; but sharp corner could be found on the bottom of pakfa. I have told you many times about this.

 

[antonius123]

@ptldm3

You see that F-117 corner is wide and face upward; it doesnt bounce back much radar wave when it get inverted, more over it doesnt bounce back radar wave from the ground when it banks