RadDisconnectWhy are you searching so much when it’s perfectly logical. This was published by Air International and not in the Huffington Post. At least, they know what they are talking and not talking about. If it was about AoA, we will have read the word Angle of Attack.
And again, side slip with gigantic canted vertical tails and non afterburner usage in a twin engine airframe makes sens.
Course of travel refers generally to the trajectory. I don’t really see why it should be read otherwise here.
Perhaps. Sustaining that side slip at Mach 1.2 is quite an aerodynamic feat. It seems like the F-22 is even more sophisticated than I had imagined.
RadDisconnectTo induce a 20deg AoA at that altitude and speed requires serious pitch authority. [Which the F-22 has due to the TVC use for supersonic trim.]
I don’t expect the Raptor to be able to sustain that, so don’t believe it to reflect excess power.
Well, the alternative explanation of 20 degree slide slip is even harder to believe, since you will need incredible yaw authority. I think you’ll need true 3D TVC like on the F-16 MATV to pull that off.
What else can that line mean then? “nose heading 20 degrees off the course of travel.”
RadDisconnectDifferent situation.. I don’t know the primary role of the Su-35S in the RuAF but I assume it’s A-A, not A-G..
In the case of the F-35, it is primarily a striker.. Our local fanboy club has fallen for a belief that it’s almighty DAS somehow manages to completely delete the drawback the bird has in kinematics. If we’re gonna believe that, then we have come to a conclusion that the USAF’s primary strike asset is a better A-A performer than the USAF’s primary air dominance asset. If true, then the air dominance asset makes no sense, anymore. Just build another 187 F-35s, assign them to today’s F-22 squadrons and the Raptors can go to AMARC. You get cost saving and fleet commonality and increase the A-A performance at the same time.
How is that logic any different from suggesting that Russia should immediately cease Su-35 procurement and go with the T-50. After all, the T-50 is a better air-to-air performer, right? My statement is that SA and stealth plays a much bigger role in controlling the engagement that kinematics, and this is generally reflected by how the F-22 operates.
The F-35 is not a dedicated air superiority fighter like the F-22, but that doesn’t mean it can’t have certain advantages even in the air-to-air regime. Don’t know why you’re trying to make absurd extrapolations from my statements.
What makes you think that the T-50’s or J-20’s sensors will be worse? Or LO for that matter? What exactly do we know about its stealth, at all?
Put it this way, if the T-50 has better stealth and SA than the F-35, then the F-35 is likely at a major disadvantage regardless of whether or not it has better kinematics than the T-50.
RadDisconnectThat does not matter that much. Finally, in order to replace a DAS by some domestically designed system with better function you don’t need to re-program the whole aircraft. You just need to make hardware/software for your part and then make sure it communicates with the system and gets integrated as whole. Not easy, by far not, but much easier than design an alternative for the F135, make all the flight tests, certifications, etc.
Again, experience from the F-35 and F-22 programs suggests that software is just as much of a developmental hurdle as flight testing and aerodynamics was. Also, look at the T-50. The most classified systems on that aircraft are the EW and missiles.
If it does, then the F-22 can be phased out immediately because it has no role in the USAF, anymore.
That’s your reaction to my assessment that SA and stealth plays a much bigger role than kinematics in controlling the ROE? So should the Su-35 be phased out immediately because of the T-50?
Kinematics helps dictate the ROE even if nothing else is equal.. A Mach 6 aircraft with a MiG-29 radar would still be a more deadly A-A adversary than an F-35. Sure, you can argue that it wouldn’t be able to detect the F-35 etc. etc. but all you’d need to do is make it datalinked with a platform which can detect it (3D radars, AWACS, T-50, etc.). A much easier and cheaper upgrade than make the F-35 Mach 6 capable..
Not sure why you’re resorting to hyperbole here. Even at Mach 6, positioning is key, and an aircraft with less SA could very well be speeding at Mach 6 into a missile. If kinematics dictate the ROE, then a next generation fighter would look more like the YF-12A than anything we’re seeing now.
Platform capabilities is what always matters. The only thing you cannot change easily. On the future T-50s or J-20s they can always hang better bling, better sensors, even better engines… only the matter of economy and budget…
You guys love to use the same logic when discussing F-35 vs. Typhoon/Rafale but completely fail to accept the same when discussing F-35 vs J-20 or T-50.
By the time the T-50 or J-20 hangs better sensors, where would the F-35 be? Yes, a T-50 or J-20 will have the edge, if they can provide the same level of SA and LO as the F-35. You seem to assume the if is a fact.
Against the F-35 pretty much all. The F-22 has no distinct advantages in electronics, finally it is more than a decade older. Can you say the F-35 reliably defeats the F-22 in A-A? If not, then it won’t defeat even T-50. If yes, then you can scrap the Raptors and look no more, you have just found your ultimate platform. Somehow I can’t see that happening..
Again, don’t know why you’re throwing around false dilemmas, or trying to use some bizarre triangular logic. Can the F-35 reliably defeat the F-22? I would still argue it depends on which aircraft can detect and track the other first.
RadDisconnectFlying at 20 degrees
In AIR International July 2015 I read in there F-22 Raptor supplement on page 55:
“It can cruise at 40’000ft at Mach 1,2 with the nose heading 20 degrees off the course of travel …”This is difficult to understand for me. What do you think about that?
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I have a difficult time believing this is sideslip angle, especially in sustained supersonic flight. The yaw authority needed would be damn high, and the fact that the two wings see such different airflow. I think it’s more likely he was talking about a 20 degree AOA, which would still be pretty remarkable. It seems like the F-22 has more excess power than I had thought, since it could go supersonic at sea level without afterburners, based on test pilot Steve Rainey.
RadDisconnectBecause it is comparatively easy. You got just a few nations in the world capable to design and build a fighter aircraft. Even less nations are there to make their own engines. But there are dozens of avionics fitters, even many you most likely haven’t heard of. That is not to say that they all can outfit an F-35 but once given access to source codes, many nations will be able to. Certainly Israel and EU. How many of these can replace the F135 by their own engine?
Seems like you’re saying avionics and software development is easy compared to propulsion development because of larger manpower pool. I disagree. In fact, software is the most expensive part of the F-35, and (IIRC) it’s further behind than everything else, including engine, flight testing, etc. Same goes for F-22 development back in the 2000s.
I disagree. Kinematics and platform capabilities are what matters. You don’t need better kinematics to survive a missile shot, you need it to dominate the ROE of your air-air encounter. It gives you capabilities to engage at will, choose your position, exploit the range of your weapons and then disengage at will.
I would say superior SA and stealth plays a much bigger role than kinematics when it comes to dominating the ROE. Having more information your opponent than your opponent has on you will more likely put you in a position of advantage, far more so than kinematics alone.
Remember, the F-35 will be facing T-50s, J-20s and J-31s, but you guys somehow get comfortable with a fact that it somehow handles an F-16 (not even that is true)..
If your SA is what matters, then the F-35s shall be flying air cover for F-22s, not vice versa. Can you see that happening?
If everything else is equal, then kinematics will be the deciding factor. But when is that ever the case? And can we really say that the T-50 and J-20 will offer equivalent capability to the F-35 in SA and LO? The F-22 is a dedicated air superiority fighter with outstanding kinematics, but how much of the F-22’s effectiveness is due to kinematics?
RadDisconnectAn upgraded engine won’t help much…
That doesn’t address the issue. I don’t know why some people like to assume that it’s somehow easy to upgrade avionics and sensors compared to hardware upgrades like improved engines. The F-22 comes to mind. It has the space and cooling provisions for side-looking radars and a dedicated IRST, but these haven’t been fitted yet, and likely won’t happen for a while because of funding and software.
Aerodynamic performance is important, no doubt. But at a certain point it just becomes a problem of diminishing returns. The improvement in kinematics from 4th to 5th gen is useful and impressive, but what really adds more to survivability is the increased SA and low observables. Better kinematics gives you better chance of surviving a missile shot, but better SA and stealth can let you avoid getting shot altogether. Assuming that 5th gen air combat will devolve into classic merge dogfights where kinematic performance is the deciding factor is rather shortsighted.
RadDisconnectHuh, I thought I hit the reply button, but I didn’t. Anyways here’s a belated response.
Well, the canopy should not be a problem for the T-50 with silica glass rather than acrylic, and another point regarding the tails (and sundry composite parts): the 1980s MiG-29 is credited with Mach 2.3+ despite CFRP fins.
I thought the max speed of the MiG-29 was Mach 2.25. In any case, I recalled that some time earlier MiG-31s were temporarily limited to Mach 2.35 due to canopies that needed refurbishment (may have been fixed by now).
What was the context for those temperature references? It sounds like they would all be equilibrium temperatures (i.e. the aircraft is assumed to be in sustained cruise) and that would certainly make sense – otherwise it’s an apples/oranges comparison, isn’t it?
True, though we don’t know how fast an aircraft reaches temperature equilibrium. But given the time it takes to perform the dash I don’t think it’s thermally less demanding than, say, flat supercruise at Mach 1.7. Even an interceptor like the MiG-31 designed for high sustained Mach speeds can be limited under some conditions.
Yeah, I think the folding mechanism is primarily a space saving measure for conformal/internal carriage rather than a drag reduction feature. Concur also on the situation regarding conventional vs. grid fins for Izd. 180 not being clear cut – I think people tend to take Piotr Butowski’s educated guess as a confirmed truth.
Perhaps, though an AvWeek article also reported conventional fins for the 180.
http://www.freerepublic.com/focus/news/2315757/posts
Curiously, Butowski said a successor to the izd.180 is the izd.270, which is supposed to be a totally new missile and not a R-77 derivative like the 180. T-3ski perhaps?
RadDisconnectThis is frustrating. With this Tu-160 nonsense we might end up seeing the LRS-B enter service before before the PAK DA. 😡
RadDisconnectIf a relatively basic T-50 is able to hold its own against Block 4 pig even without datalink and with the Pk dubiously shifted in favor of the AIM-120D, then it’s a good sign of the platform itself being superior.. You gotta consider the overall upgrade potential of those two – you can shift the results in favor of the T-50 relatively easily by adding a better radar (GaN), stealthy datalinks, better passive sensors, new RWR etc.. but you can never make the F-35 match the PAK-FA in terms of kinematics, it will forever stay in a disadvantageous position.. just like you can’t make a Typhoon or a Rafale stealthy..
BTW, I have no doubts that the T-50 will have datalinks (whatever “Block” should that be) so the point is kinda moot, anyway.. Thanks for your effort, BTW…
Why do you assume that it’s somehow relatively easy to add “better” radar and avionics (and the associated software) than, say, an engine upgrade?
RadDisconnectI think I’ve read that the lattice fins of the R-77 (and RVV-SD) can fold for lower drag, but I don’t think I’ve ever seen this actually being done when mounted on aircraft. Though it’s a moot point, since the izd.180 (K-77M) has conventional rear fins.
RadDisconnect1. If the speed requirement in question is in the M2.0 ball park (and was lowered due to structural concerns), then the issue is probably thermal in nature rather than dynamic pressure.
2. For brief periods (i.e. transiently dashing to top speed), it is perfectly possible to reach Mach numbers which the structural materials could not tolerate in thermal equilibrium – i.e. supercruise, not top speed, is likely to be the ‘long pole in the tent’ in this respect.
3. If, of all structural parts, it is the vertical tails which define the limit with regard to this speed requirement, composites should not have any bearing on the issue at all. On the T-50 the tails appear to be metallic, most likely SPF/DB titanium (think Typhoon/Rafale canards – a benefit of their reduced size).
Again, for all I know the inlets might only be this complex to ensure adequate cruise performance with the interim engines, but assuming they don’t change the T-50 looks to me like flat out it ought to be good for a lot more than Mach 2.0.
Are they? Well, I’m not – my point is merely that Berkut et al do not have the information needed to confirm their opinion either.
Quite. Again, I’m just pointing out that the required specifics about the T-50 are not known one way or the other, so either assumption is equally valid for the time being.
Exactly my point. From what is currently known, it could go either way.
Without variable ramps, wouldn’t F-22 inlet performance taper off more quickly at Mach numbers higher than the design point (which would sensibly be the supercruise condition), where it would be very good – perhaps *better* in fact than a variable ramp inlet? If those ramps on the T-50 were merely for supersonic cruise efficiency, it’d be pretty weird – almost like Concorde (i.e. its cruise speed equals its top speed to all intents and purposes).
EDIT: Another possibility is that the T-50 has absurdly high supersonic acceleration requirements to meet, necessitating inlets that work efficiently over a wide Mach number range (even though it is not required to exceed Mach 2.0)?
Certainly some design elements of the T-50 seem to suggest max speed, but evidence from program requirements are still somewhat difficult to reconcile. Honestly I don’t think the max speed will be greater than Mach 2.35, since that was the initial PAK FA RFP requirement, and higher dash speed just isn’t compelling given the ongoing MiG-31BM modernization and planned dedicated MiG-31 replacement. IMHO, Mikhailov’s statement about speed adjustment was made in the context of max speed. And true that the upper right of the envelope tends to be limited by heat instead of q (dynamic pressure), but I don’t think we can say that max dash speed doesn’t present as much of a thermal issue as supercruising. I believe the abrupt cutoff of the F-15’s envelope is due to heat (allegedly due to the canopy). I’m not sure how fast an aircraft achieves thermal equilibrium, but achieving dash speed requires accelerating through the Mach, spending a limited amount of time (minutes) at that pursuit speed before slowing down. Thermally I don’t think we can say max speed is less thermally demanding than sustained supercruise. Quoting Advanced Tactical Fighter to F-22 book, aerodynamic heating at typical supercruise of Mach 1.5 causes 150 F rise in skin temperature, while it’s 230 F at Mach 2, and 500 F at Mach 2.5. Also, perhaps when speaking of materials, it’s not so much the structural but rather RAM and the need to prevent it from degrading rapidly for maintenance and cost reasons.
RadDisconnectSorry what I meant was RVV-MD , can it carry RVV-MD size missile on those wings internal bay ?
What is the 700 kg weapons that PAK-FA can carry ? Also any small SDB type under development ?
The launcher is rated for 700 kg, doesn’t mean all weapons will be that heavy.
Some of the heavier weapons include the Kh-58UShK anti-radiation missile (or some more advanced variant of it), which is about 650 kg (1,430 lb), the long range izd.810 AAM (probably similar size to RVV-BD, 1,320 lb or 600 kg), and Kh-38 air-to-surface missile which is about 520 kg (1,120 lb).
Basically, the T-50’s design allows it to carry four Phoenix-size missiles internally, quite impressive.
RadDisconnectYes to sustain very heavy and draggier platform (its NTOW is weight about 150% of F-16) it need lots of fuel. and i bet JSF is faster than so called 10 ton F-16E.
Why do you need to bet? You can easily find their dash speed number, it’s open source. You’re not even trying now.
Those Su-27SK was soviet creation and much simple structure. Su-35 much more complex structure. Very big difference.
What difference? How is it at all related to the fact that there’s NO indication that “export” Su-35 somehow has different performance?
There is no such thing as wish. it is proven beyond doubt. T-50 having more powerful engines than MIG-31 with sleekest aerodynamic form with newest materials built into its structure. even Mach 3 is understatement.
:highly_amused:
Do you know what proven means? You have given absolutely zero sources. Are you deliberately being stupid right now? About the only thing your post is saying is:
RUSSIA STRONQ
Say what you will about JSR’s “reasoning”, but at least he can be a source of pure comedy. :very_drunk:
RadDisconnectThanks , What about the missile launcher near the fuselage/wing area for PAK-FA ? Can they carry the RVV-SD internally or will they only carry the newer SRAAM under development ?
IF each bay can carry two 700 kg bomb , can you identify these standoff/LGB types weapon they can carry ?
Those are SRAAM bays, and there’s no way to fit an RVV-SD (or anything R-77 size) in there. A R-73 derivative called izd.760 (K-74M2) will go in there and it allegedly has reduced cross-section and HOBS capability similar to the AIM-9X and ASRAAM.
why did Sukhoi increase the fuel capacity. it is to maintain much higher speed than Su-27. Su-35 is titanium and composite developed in late 80s for EF has no relevance to composite developed in 2010 for PAK-FA.
:stupid: So by that logic, did the F-35 have more fuel than the F-16 for higher max speed? Oh, and in your incessant non sequiturs and changing of topics you have forgot why you even brought up the Typhoon.
It is based on solid evidence that export fighters are downgraded compared to Ruaf. Export Su-35 is 2500km/hr from public statement. Su-35 also carries the biggest pods on the wing tip.
That is not evidence. You have NO evidence that the “export” Su-35S has different performance. None. Zero. Export Su-27SK has difference in avionics, but its performance is the SAME as the VVS Su-27S. You’ve debunked your own claim. And what does the Su-35’s wing pods have anything to do with this discussion?
No amount of wishing from you will make the T-50 even touch Mach 3.
RadD@
I have put JRC on my ignore list for weeks now. I strongly suggesting u do the same.
It just Hurt my eyes and brain seeing you trying to reasoning with him.
God knows I tried, sadly I failed utterly..
I’ll keep reporting until a moderator does something about him. It’s hard to let such stupidity go free, and it should have no place here.
That looks like a stupid math error to me, because it says “2.0 Mach (1521 mph)”
Speed of sound at sea level is roughly 761 mph. Some idiot simply multiplied it with 2 and wrote it there. Otherwise source is in severe error, 1521 mph at altitude is not M2.0, and M2.0 is not 1521 mph.All in all, Typhoons top speed is M2.0 according to any reliable source one can found.
I looked around, and the Austrian Luftwaffe website was a bit more specific.
http://www.bundesheer.at/waffen/waf_eurofighter.shtml
2,495 km/h at 10,975 m altitude, which translates to Mach 2.35. Again, this may not be the Typhoon’s operational speed limit, which is probably lower (around Mach 2).
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