Berkut Posted March 22, 2010 Share Posted March 22, 2010 There´s something fishy about that pic of the intake.... first of all the intake duct seems very shallow. Like Gregg suggested, it might be a similar thing as the Super Bug intake. http://www.freeimagehosting.net/uploads/8524420b3c.jpg And the pic is taken at such an angle that you look straight into the duct, I don´t think that much would show on a pic taken directly in front of it. They are called radar blockers, the thingys seen in Super Bug intake. Less effective than S like on Su-47, B-2 and F-22, but still eats some RCS. However, insider claims there is no radar blocker on T-50-1, and that they will install it on T-50-3. So basically, we see the good ol' engine. If i had said i was not disappointed, i would have been lying. :wacko: So yeah, a bit disappointed the lack of S intake, since Su-47 has it. Not sure if they will implement S intake on later prototypes, but if the information about T-50-3 is right, they seems to be going just for radar blockers ala Superbug. Hopefully a combination of S intake and radar blocker. Quote Link to post Share on other sites
ross blackford Posted March 23, 2010 Share Posted March 23, 2010 , Chin up Berkut, I'm sure the production aircraft will have a very LO characteristic. Somewhere earlier in the thread was an exploded view drawing of the aircraft. Go back and have a look at the twists and turns in the intakes on that baby. Up and over the main wheel wells, That's two bends and then inwards towards the engines two more bends. Just speculating here, (yes I know, but I'm tired and can't help myself; that's my excuse and I'm stickin' to it) but if that drawing is anything like the real thing and there are radar blockers inside the prototypes intakes, so they may appear on production birds as well, the production machines will likely have very LO intakes. ;), Ross. Quote Link to post Share on other sites
GoBlue96 Posted March 23, 2010 Share Posted March 23, 2010 <snip>Not sure if they will implement S intake on later prototypes, but if the information about T-50-3 is right, they seems to be going just for radar blockers ala Superbug. :D Hopefully a combination of S intake and radar blocker. Man, I don't know. Speaking as a aircraft design engineer, that's a whole lot of a redesign. The engine and intake footprint has a pretty large impact on the design of the rest of the structure of the aircraft. Unless they were just trying to get the aircraft in the air to make some sort of deadline, I don't have any real idea why you'd fly a prototype with a different shaped intake than you want later aircraft to have. Of course prototypes fly all the time with different features/different design than the actual production version (we've already talked about the YF-22 as compared to the F-22). In my opinion, it's one thing to fly the PAK FA prototype with a two piece canopy and then fly later aircraft with a one piece design, for example, or even to come back with something like larger vertical tails (which actually might be easier than a one piece canopy, depending on how the vertical interfaces with the aft fuselage) and an entirely different matter to redesign the inlet trunks. The inlet trunks interface with the rest of the airframe along their entire length instead of just a couple of points. There would also probably be plumbing impacts and other systems that would have to move and be redesigned. I'm not saying it couldn't be done or that it wouldn't, I just don't see the point of it unless they are being intentionally deceptive with how the prototype looks. It would just be a whole lot of engineering hours, not to mention potential new tooling and parts and all that sort of thing. It just seems odd that they'd go through all that effort. Quote Link to post Share on other sites
Berkut Posted March 24, 2010 Share Posted March 24, 2010 (edited) Now, this is a very interesting solution... http://www.youtube.com/watch?v=SvarEU9oEIY...player_embedded If it really works it does two jobs at once: 1- It regulates the airflow. As far as i know, every single jet engine in production must have airflow below supersonic speed. So, the usual airflow regulator isn't needed. 2- Stealth. Edited March 24, 2010 by Berkut Quote Link to post Share on other sites
Jonathan_Lotton Posted March 24, 2010 Share Posted March 24, 2010 Now, this is a very interesting solution...http://www.youtube.com/watch?v=SvarEU9oEIY...player_embedded If it really works it does two jobs at once: 1- It regulates the airflow. As far as i know, every single jet engine in production must have airflow below supersonic speed. So, the usual airflow regulator isn't needed. 2- Stealth. Not as stealth as it should be because the engine face is still visible, even if the initial compressor stages arent. Quote Link to post Share on other sites
Berkut Posted March 24, 2010 Share Posted March 24, 2010 (edited) Not as stealth as it should be because the engine face is still visible, even if the initial compressor stages arent. It would be hard for radar waves to bounce back through that tube again. I am not sure what you mean by engine face tbh. Edited March 24, 2010 by Berkut Quote Link to post Share on other sites
ross blackford Posted March 24, 2010 Share Posted March 24, 2010 Not as stealth as it should be because the engine face is still visible, even if the initial compressor stages arent. Hmmm. 'What if' the variable vanes of this simple device and the end faces at both ends were coated in RAM? What then? What a simple way to solve the problem. When I first looked at those 'engine faces' in that tweaked pic a page or two back there was certainly something fishy about it and I thought then that the 'engine faces' were much too close to the intake lip for them to be the actual engine compressor faces, based on the known length of the aircraft, the known the known distance from the intake lips to the known postiton of the engine compressors and the known length of the engines, about 1/4 of the length of the aircraft. These devices give an explanation for the short distance between the intake lips and the 'compressor faces'. Perhaps the Russian engineers adhere more than we do to the 'KISS' principle, Keep It Simple Stupid. Over the last 20 odd years I've noticed that we in the west have gone down the road of increasing complexity to solve problems, regardless of whether they be complex or simple. In fact, the more complex the problem, it appears the more complex the solution has to be in western thinking. I've said on numerous previous occasions in these forums that the Russians have vastly different design philosophies from we westerners. Does that make their solutions to problems inferior or impossible? Not in my personal experience it doesn't. Back in the late 1950s-early 1960s the BHP company (then Australia's largest steelmaker) was looking around for a more modern steelmaking technology to install at their Newcastle steel plant to supplement the then blast furnace technology they'd had in use since WW1. The technology they finally decided on was Russian. Not only was it the cheapest and simplest Basic Oxygen Steelmaking process available but also the most productive and required the least maintenance. It served BHP at Newcstle for 38 years until they shut the plant down 10 1/2 years ago as the rest of the plant had been there since 1915 and it would have been too expensive to upgrade it and replace machinery that was many many years old at that stage. , Ross. Quote Link to post Share on other sites
GreyGhost Posted March 25, 2010 Share Posted March 25, 2010 I don't know Ross, for 'keeping it simple', there sure are a lot of moving surfaces on this aircraft ... Gregg Quote Link to post Share on other sites
ross blackford Posted March 25, 2010 Share Posted March 25, 2010 (edited) :D, Hi Gregg, Perhaps I should have expressed myself a bit better there. I was referring only to the intake system. GoBlue96 made the statement that it would be difficult to have straight intakes on the prototype and S-bend types on the production machines because the intakes are an integral part of the design and difficult to change from prototype to production. Although I did notice in looking at pics and profiles fo the Sukhoi T-10 that it had more curvey intakes and the production Su-27 has much straighter ones. If this twisty vane technology is a success and I'm sure they would have tested it both aerodynamically and RCS wise there will be no need for the production machines to have complex bendy intakes. The twisty vanes will do both jobs. Things that seem non-sensical to us often make perfect sense to other peoples in the context of their situation, environment and culture and when open minded westerners have these things explained to them they can see the reasoning behind the way things are done in other nations. At the Bicentennial Airshow at Richmond in 1988 I asked an English speaking engineer why they had designed the undercarriage of the An-124 as they had. "Why not make it like the C-5?" I asked. "Two reasons" he replied, "weight and drag. It doesn't need to be so heavy, our system does the job just as well as the C-5's, and because there are more wheels heading into the airflow on the C-5 with the undercarriage down and locked there is more drag, 8 main wheels facing directly into the airflow on the C-5 versus 4 wheels on the An-124. And added to that our undercarriage doesn't have to rotate to retract so there isn't all that extra drag during undercarriage retraction which often comes at a critical time in the flight regimen." When he'd explained all that to me it all fell into place. I do agree that there seem to be a lot of moving surfaces ont he PAK-FA, but are there really, compared to the F-22? Does the F-22 have LE slats? If so then by my calculations the PAK-FA has 2 less moving surfaces as it has all flying vertical tails, no rudders. I can't say if this is correct off the top of my head, I'll have to have a look at pics of the F-22 to be sure. :D, Ross. Edited March 25, 2010 by ross blackford Quote Link to post Share on other sites
GreyGhost Posted March 25, 2010 Share Posted March 25, 2010 The PAK-FA has all moving vert stabs, thats the same as two rudders moving and it also has those forward moving surfaces just above the intakes as well ... It is supposed to have 3D TV nozzles where as the F-22 has 2D nozzles ... And if this intake vane set up comes about, those are more moving surfaces ... To me, the simpler solution would be curvy intakes ... Or like how the Super Hornet takes care of the problem ... And the C-5's landing gear wasn't over-engineered, it was designed for a wider footprint for use on unimproved runways much like even the later C-17 has wide tracked landing gear ... The C-5s landing gear also has to handle heavier loads ... Gregg (Who got to see an An-124 and C-5B parked next to one another in 1988 in San Diego...) Quote Link to post Share on other sites
MiG31 Posted March 25, 2010 Share Posted March 25, 2010 I think a point to take away from this is not necessarily that it has to be a simpler solution, or even more complicated, but simply different. Why does the way the US do it have to be the standard, or only way, to do things? This editorial makes a good point on that. And the C-5's landing gear wasn't over-engineered, it was designed for a wider footprint for use on unimproved runways much like even the later C-17 has wide tracked landing gear ... The C-5s landing gear also has to handle heavier loads ... Not to take this thread further off-tangent, but how do you know the C-5 has to handle heavier loads than the Ruslan? On the unimproved runways part, who's to say that the ? Quote Link to post Share on other sites
GreyGhost Posted March 25, 2010 Share Posted March 25, 2010 I think a point to take away from this is not necessarily that it has to be a simpler solution, or even more complicated, but simply different. Why does the way the US do it have to be the standard, or only way, to do things? This editorial makes a good point on that.Not to take this thread further off-tangent, but how do you know the C-5 has to handle heavier loads than the Ruslan? On the unimproved runways part, who's to say that the ? Look how different YF-22 and YF-23 were and those were from the same country with the same design spec given to both companies ... C-5 can carry a heavier load ... read up about it ... I didn't see that An-124 land or take off from that ... :( Gregg Quote Link to post Share on other sites
MiG31 Posted March 25, 2010 Share Posted March 25, 2010 (edited) Look how different YF-22 and YF-23 were and those were from the same country with the same design spec given to both companies ... And? How does that refute my point, that other countries can take different approaches than those taken by the US? I'm not going to continue with the An-124/C-5 tangent. Edited March 25, 2010 by MiG31 Quote Link to post Share on other sites
GreyGhost Posted March 25, 2010 Share Posted March 25, 2010 And? How does that refute my point, that other countries can take different approaches than those taken by the US?<....> Just that 'different' doesn't only happen from other countries or cultures ... Gregg Quote Link to post Share on other sites
ross blackford Posted March 25, 2010 Share Posted March 25, 2010 :D, Oh dear, Oh dear, :o What have I started here? :D Yes Gregg, you're right about the vertical stabs. As yet we're not sure about those moving canard like surfaces above the intakes, they may be the simplest solution to a very complex aerodynamic problem that has been shown up in wind tunnel testing. I also agree about the intakes themselves, but we don't yet know all the ins and outs of this issue. Likewise the twisty vanes may be the simplest and cheapest way of dealing with a couple of very complex problems that presented themselves in wind tunnel and RCS testing along the way. I'm sure that one day all will be revealed. BTW Gregg, I was able to examine in detail both the An-124 and a C-5A at the Bicentennial Airshow in 1988. Admittedly, they weren't parked side by side, but within a couple of hundred meters of each other. :) :(, Ross. Quote Link to post Share on other sites
MiG31 Posted March 25, 2010 Share Posted March 25, 2010 Just that 'different' doesn't only happen from other countries or cultures I see your point there. I suppose my misgivings come from reading discussions on this subject, not just on ARC. The intake geometry issue seems to be the highest-profile subject on that, and while the F-22 apparently has a good means of blocking radar returns from the inlets, that is not to discount the production PAK FA's ability to do so in its own manner. Back to the topic of the Ruslan vs. Galaxy, you gave the impression that the C-5's gear was more rugged than the Ruslan's, hence my response. Quote Link to post Share on other sites
ross blackford Posted March 25, 2010 Share Posted March 25, 2010 , Perhaps I should start a comparo thread on the An-124 versus the C-5. My only fear is that it would head south very quickly, unfortunately. I'd like to see peoples' views on the two aircraft as compared side by side. , Ross. Quote Link to post Share on other sites
Berkut Posted April 8, 2010 Share Posted April 8, 2010 Arrived in Zhukovsky. So far there have been 6 flights in total (i thought it was 3 all the time, before it was disassembled) and the flights will resume in end of April /beginning of May. http://www.sukhoi.org/news/company/?id=3262 Quote Link to post Share on other sites
Flankerman Posted April 8, 2010 Share Posted April 8, 2010 Arrived in Zhukovsky. So far there have been 6 flights in total (i thought it was 3 all the time, before it was disassembled) and the flights will resume in end of April /beginning of May. http://www.sukhoi.org/news/company/?id=3262 Thanks for the link Berkut - lets hope for some good photos soon... I need are some decent photos of upper and lower surfaces showing the splinter camo scheme. My scratchbuild PAK FA is nearing completion - so I am starting to think about painting it. I can't decide whether to do it in its prototype colours - showing the primer parts - or do the camo....... I quite like the primer scheme................ but until there are good photos of the camo, I can't decide Ken Quote Link to post Share on other sites
mario krijan Posted April 8, 2010 Share Posted April 8, 2010 Now we will get much more photos from Moscow!!! :-) Quote Link to post Share on other sites
ross blackford Posted April 8, 2010 Share Posted April 8, 2010 :D, Which will be good to see. <_<, Ross. Quote Link to post Share on other sites
Berkut Posted April 29, 2010 Share Posted April 29, 2010 (edited) It is flying in Zhuk again. No pictures so far. From http://photo.strizhi.info/. Taken by airwolf. Bigger res: http://photo.strizhi.info/v/airwolf/airwol...ageViewsIndex=2 http://photo.strizhi.info/v/airwolf/airwol...ageViewsIndex=2 http://photo.strizhi.info/v/airwolf/airwol...ageViewsIndex=2 + underside: More fun: http://take-off.ru/index.php/news/93-april...-lii-29-04-2010 Edited April 29, 2010 by Berkut Quote Link to post Share on other sites
Raymond Posted April 29, 2010 Share Posted April 29, 2010 that is freakin sweet! Quote Link to post Share on other sites
mario krijan Posted April 29, 2010 Share Posted April 29, 2010 Great looking! but it would be sexier to have taller vertical fins! Quote Link to post Share on other sites
wh1skea Posted April 29, 2010 Share Posted April 29, 2010 diggin' the blue camo. :D Quote Link to post Share on other sites
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