Siege has posted the link below, did you find it? Its another thread entitled translation of amatuer text, Dr Songs paper is translated later in that same thread.
---------- Post added at 10:12 AM ---------- Previous post was at 09:38 AM ----------
This would indeed be a first if he is talking about this large of a section of the external skin, vic do you get the sense of whether this would include bulkheads formers etc, or have they cut down the number of these supporting structures. We forge bulkeads, attach point hardware etc, but this large of a machined part is a new one, and it may well be cast or forged, it would be interesting to know for sure. We have had wet wings for a while, could this be a wet fuselage, although some sort of baffleing would be neccesary, to prevent the fuel from vaporizing as it sloshed around, I am interested in the source of this translation?
---------- Post added at 11:09 AM ---------- Previous post was at 10:12 AM ----------
Yes it is siege, and this is what totally freaked me out about two months ago when the eng and mig each provided some separate links the first to Dr. Songs paper, part of which eng, pugacheve diver, and maybe no-name had translated and posted on this thread and another that mig had posted from 1991, which was very helpfull as well, and your translation in amatuer document helped to jell. If you could see the control surfaces on the trailing edge of the main wing, you would find them deflected upward in relation to the main wing, but those canards deflected downward just seemed wrong. Well here's the story in laymens terms for all you guys like me who hate algebra. Starting at Front.
1. The forward fuselage section is shaped as a lifting body, in part to compensate because the center of lift of the main wing is so far aft.
That means the canards have to be in the same plane as the lifting surfaces and main wing, these canards are distant coupled, and also control canards. All this lift is wonderfull and necessary, unless.......
2.You are at a high angle of attack, then all this lift tends to over pitch your aircraft, especially if you are slow and deep into your high AOA regime, so then you have to take countermeasures and spoil all this lift, the way you accomplish this if you are the J-20 engineers is to program the flight control system to pitch the nose down. This prevents the aircrafts departure, Dr Song was emphatic, that even if the J-20 where to employ TVC, you must have sufficient aerodynamic control to recover the aircraft to normal flight in the event of TVC failure.....
3.Having said all this, this is a very, very busy Flight Control System as our brother Tianlong noted, yes, it would be advantageous to employ TVC if you want to supercruise in order to minimize super sonic trim drag, but IMHO I think they will see how all this shakes out first, they may decide thats complexity they don't need, because this airplane has all the performance they need, especially now that there will be no more Raptors, its production capped at 187. So how does all this good transonic control play out once you go supersonic. Well ask Tianlong, or Dr. Song, or one my mentors eh? ........ or maybe the tallman?
