There seems to be a general lack of knowledge of stealth principles and I think I will release a new video in the next few weeks to explain the differences among the J-20, F-22, F-35, and T-50. I suggest that people, who are overly nationalistic, should not watch it. It will be an objective and clinical discussion of the proper and improper application of stealth design principles for all four fighters.
And
YOU are a member of that group. That is funny that you could say that considering what you learned of the basics of radar detection and rudimentary 'stealth' techniques came from me. And yes, I dare say that. But we will examine a couple of points of your arguments.
From my time in front of many groups, I know that the more colorful the charts, the less clarity the subject. Your kaleidoscope of the J-20 wrapped in many colors serves only to confuse the genuinely interested laymen and to awe the gullible. I will give the readers something more simple but much more clarifying to the basic principles that you do not know but lies about knowing.
We know that structurally speaking, the diverter inlet plate assembly is more complex than a DSI 'bump', however, your argument is clearly deceptive for those of us who know better...
(Note the J-20 air-inlet has been better integrated into the fuselage than the F-22's gap between the air-inlet and fuselage.)
China's J-20 is the new gold standard in front-profile stealth. The J-20 has both a serpentine air-duct and DSI bump to hide the engine compressor blades. Due to its older design, the F-22 lacks DSI bumps.
The simplistic implication here is that because the DSI system is allegedly 'newer' therefore the older diverter plates must be detrimental to the F-22's radar cross section (RCS).
Utter garbage...!!!
In as complex and spatially dynamic body as an aircraft where RCS control is paramount, the greatest contributors must receive the greatest attention and contributorship reduction treatments. That mean the fuselage, flight controls elements, external stores, and engines. Obviously we cannot eliminate the fuselage and today we still need flight control surfaces of varying sizes. When we can no longer treat them, either through shaping or other methods, we can then work our attention to lesser contributors gradually like the cockpit area, comm antennas, and so on.
From the airliner's RCS graph above, would it be worth it to turn out attention to the cockpit or the fuselage or anywhere else? No. That single vertical stab will overwhelm even the crudest video display of any other aircraft characteristics that may cluster with it. If its RCS contributorship cannot be reduced, not to zero, but to some reasonable degree, then it would be worthless to treat everything else on the aircraft to lower them below a certain threshold. That is like seeing a shark's dorsal fin moving above the surface but nothing else of the shark because of the water. Even in a frontal RCS view, the vertical stab's edge length can still be among the dominant contributors, if not the greatest.
So why does the J-20 has a DSI inlet system?
We know that diverterless supersonic inlet (DSI) system is not new. The F-111 has it and its DSI 'bumps' were moveable at that. We call them 'translating spikes'...
So if we know that the DSI system pre-dated 'stealth' we can rule out the absurd argument floating around that DSI was created as an RCS control method. Any RCS reduction for the engines due to the DSI inlets are purely incidental, meaning as a by-product, not because DSI was originally intended for 'stealth' and it can be reasonably argued that since there is a side benefit we should use it anyway.
We will now examine another bit of stupidity that ties in with the previous one...
I have two observations. Firstly, as shown in the spliced-photo above, I believe that I have been proven correct that the J-20 matches the F-22's frontal profile in stealth design.
You have proven nothing more than your argument is for the gullible and the stupid. But we are willing to humor you so assume --
JUST ASSUME FOR NOW -- that what you say is true despite the lack of credible data.
If the J-20 need the DSI system in order to match the F-22 in terms of frontal RCS then two possibilities are of note:
- That the J-20's frontal RCS must have been higher than the F-22 and that the DSI system was needed. This does not bodes well for China because it heavily imply that China does not have the technical expertise to match US.
- That despite the diverter plates structural complexity, the F-22's entire inlet system turned out to be far less significant RCS contributors than thought. It is not that difficult to reason out: That Lockheed shaped all the major contributors so well that lesser contributors do not need as much attention or even none at all.
Remember, this is based upon the very generous assumption that frontal RCS for both aircrafts are statistically insignificant in difference.
But what if we remove this assumption? For all we know, Lockheed could have found out that enlarging the F-22's inlet volume, or make the fuselage 'thicker' to accomodate more fuel, or make the fuselage wider to carry more weapons, actually increased frontal RCS than having those 'conventional' diverter plates. Removal of this generous assumption will make the F-22 the greater standard than it already is when compared to the J-20. We do not know. So for you to demand that we cannot judge 'stealth' based upon looks but
YOURSELF do exactly just that is the delicious irony that we all enjoy at your expense. I do not care if both are shaped similar. What matter is credible technical data. For all we know, the J-20 may be 'out of shape' just enough to make more detectable than you want to admit. Do not tell me that I do not know the semantical and contextual differences between 'looks' and 'shapes'. I used to be in the industry, buddy.
From a stealth design perspective, there is no effective difference between placing two little winglets (i.e. canards) in front of the main wings or behind them (i.e. tailplanes).
That is technically false. This is real physics, not Chinese physics. All flight control elements are EM radiators (generators) and because real physics demands these signals interact with each other their positions on a complex body matter. The canards' diffracted signals will interact with the wings and fuselage creating higher odds of detection.
And finally, the J-20's DSI 'bumps' are not detrimental to RCS but the F-35's various 'bumps' are. Must be Chinese physics.
---------- Post added at 08:25 PM ---------- Previous post was at 08:22 PM ----------
Put a quark in it, many of the thanks you receive are nothing more than a mutual suck-up fest. Post a picture receive 10 tanks. Post something like long live China Pakistan friendship receive 10 more thanks.
It really is sad that the man must resort to this low level of narcissism where he has to reinforce his ego by boasting about those mostly worthless 'Thanks' for mostly useless posts.
