Yes, *but* it also has implications for average cross sectional area. Higher fineness ratio means you’re distributing volume along a longer length.
J-20 - physical parameters and other overflow from main thread
- Thread starter latenlazy
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Exactly, and I'm very happy to see Webby finally got through with that wagon load of Winchester's for you "Texas Rangers",,, nice shooting cowboy!
Guys ... maybe a strange question esp. since I'm most of all interested in NEWS, fancy images and serial numbers but most recently - probably due to the fact that since 1. October nothing new was heard on the J-20 - here in this thread and in other too (aka the FC-31) there are pages of endless discussions on weight, manufacturing techniques and estimations ... not really directly related to both these fighters.
So my question ... should I leave it as it is or shall we move these part out into a new dedicated thread for discussing such technical issues?
What do You think?
Deino
By the way ... this is a J-20A ... for those who already don't know how it looks like
View attachment 43882
Move em out, feel free to start with mine, not our best efforts in any regard, Brat!
Probably best to move it.Guys ... maybe a strange question esp. since I'm most of all interested in NEWS, fancy images and serial numbers but most recently - probably due to the fact that since 1. October nothing new was heard on the J-20 - here in this thread and in other too (aka the FC-31) there are pages of endless discussions on weight, manufacturing techniques and estimations ... not really directly related to both these fighters.
So my question ... should I leave it as it is or shall we move these part out into a new dedicated thread for discussing such technical issues?
What do You think?
Deino
By the way ... this is a J-20A ... for those who already don't know how it looks like
View attachment 43882
I feel like we might want to split these threads into a subject specific news thread (I don’t feel the general PLAAF news thread is sufficient for this...) and a discussion thread. I’ve long felt that we need some form of archiving for primary sources so people don’t have to dig through pages of sometimes meaningless discussion just to find old information. It would also save a lot of trouble when we do have these debates, since I’ve noticed a tendency for contentions to arise when people bring up old information others may not have seen for whatever reason.No, ... it was not a critic but just a question and I know I'm in fact strange with my main interest in news and number.
You can't be serious. In three consecutive comments I told you that a good faith discussion can't happen if one side insults the motives of the other. You did it anyway, and now you whine when I share my observations about your motives.
What was I not honest about before?
Did this somehow come across as hostile? I literally just said that I'm not American and don't see things from their perspective. Your previous post read to me like my saying "potential enemies, such as Azerbaijan" might to you.
Good one. I'm very open to Chinese military developments and progress, but there are still naturally things that are, in my understanding of that progress, outside the realms of the probable. If you think about it, you can come up with some examples (12 tonne J-20? 5 tonne?). Or maybe not.
I was in fact mocking your pretenses and inflated sense of importance.
Had Hillary won, a direct line to the White House? Real shame about that.
I'm glad you finally got around to providing your own cross section estimate. Good job.
Did you not read what I said? I wasn’t insulting anyone’s motives (certainly not yours, at least not until you decided to make our discussion about me). You asked me for reasons which might substantiate why we should believe some claims. I don’t think it’s outside the scope of a normal response to also talk generally on some observations for why people might reject those claims on weak basis despite available evidence.
Tbh it came off as a bit standoffish and was kind of out of the blue, as if you were implying that nationality had something to do with our disagreements, when I really wasn’t trying to bring nationality into the discussion. I generally get the feeling that you’re reading a lot more into mine (and sometimes other) people’s comments than what’s there.
The YF-22 demonstrator was 15 tonnes. As I said when I first brought this point up, you can only take that example so far, as we are talking about a demonstrator, but there are ways to get weight down with certain conditions and trade offs. As I keep saying, you don’t have to believe it. You asked for my thoughts and i shared them, I’m not trying to persuade you of anything. Take it or leave it,
It takes quite a bit of pretension and self importance to assume this about others, especially when you asked *them* for their thoughts first.
No. A few friends in think tank world here and there. Maybe you shouldn’t be so presumptuous about people you don’t know, hmm?
Estimates which demonstrate my point (though I myself wouldn’t endorse them for serious analysis because of potential measurement errors, which is why I didn’t post them, and why I have generally maintained not making hard and sweeping conclusions)? Do you even care at all about the substantive discussion or is this purely about extending personal quarrels with me? I’ve consistently provided evidence when asked for it. On the other hand, you still haven’t contributed anything of substance. You’ve spent most of your time here trying to do the stuff you seem to feel fit to lecture others for (like “nitpick” and “blowholes”, except with little more than personal attacks) and being much less earnest about it to boot. So much for your own standards of “fairness”. Good job.
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If I may add as a reference to the discussion, the cross sectional areas of the J-20 vary across its length much more than the F-22, especially after the weapons bay section.
That's a somewhat unflattering F-22 picture though - because its fuselage sides slope at a shallower angle and are more blended toward the rear than on the J-20, there is less contrast at the ventral edge which can give the impression that little waisting occurs in the rear fuselage.
While that's perhaps still a bit less pronounced than on the J-20, the F-22 rear fuselage seems to taper slightly more in the vertical plane:
Doesn't seem like a huge source of error, all in all.
The trough between the engines could work both ways - by reducing the depth of the structure in that area they may actually weaken it and require reinforcements (a case of "holes being heavy", similar to the weapons bays).
Here's a reminder of some things that have been said in this discussion.
You: "That said, for the J-20’s weight to be exorbitantly greater relative to its peers though (such as 25 tonnes) would require believing either the PLAAF wasn’t aiming for a competitive fighter, or that they’re incapable of producing something that would fit the specs of a competitive fighter, or that they’re incompetent. We know from everything officials have said publicly and from documents like the program tender that the J-20 is supposed to be a competitive fighter to the F-22 though, and any three of those assumptions smacks of the sort of condescending biases and baseless prejudices that have led to underestimation before."
This was the beginning of the motives thing. Even if you weren't explicitly talking about me, who was this about? Some unrelated bigots? Why bring it up if you weren't implying these are my motivations? Oh, I see it now. You set up a straw man bigot who shares my position. Good job.
Me in response: "Alternatively, fighter development is an extremely complex undertaking and weight creep is commonly seen in programs around the globe. The 611 Institute doesn't have to be incompetent or incapable to be forced into trade-offs that could result in a weight greater than the 'baseline' 21 tonnes. I'm not saying that this actually happened, just that it is not something that can be obviously ruled out.
I don't find imputation of negative motives, even without direct attribution, to be conducive to good faith discussion."
Your response: "Some part of that is assuming Chinese aerospace isn't up to meet that challenge though, and if you delve into the "why" behind that question sometimes the reasons are grounded in some rather flippant or unpleasant beliefs. The PLAAF tendered for a fighter that could match the F-22, and the PLAAF is purported to be very happy with the J-20."
What kind of standard of debate are you using when your go-to response is to try and cast doubt on the other person's integrity instead of addressing the argument? Okay, again you did it without directly referring to me, but who else could it be about? Bigots at the gates? Plus, you were totally wrong on the issue. Nobody would have objected to a statement like "maybe Lockheed was forced into some trade-offs on the F-22/F-35/whatever program, as it's a complex undertaking." That reads basically like a truism.
This is all on page 130.
After this, I told you in two additional posts that your standards of behavior are low before I responded in kind in the fourth. I stand by all my points. There isn't anything left to discuss.
manqiangrexue
Brigadier
Although holes can be heavy, I would think that if this were that situation, the designers would have flushed out the trough for a fully flat bottom to get the weight savings all the while increasing internal volume available for upgrades. Might have some stealth or aerodynamic implications, though, for good or for bad.