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I still don't understand why you quoted me for your original message. Probably you just mixed up my posting with someone elses, it's easy to do. This was my original message:
"First of all there is a big difference in weight, but most of all you clearly has not understood how a turbofan engine works. The official thrust is at sealevel, but probably not even the Raptor SC at sealevel. Instead the chanses are much bigger at medium level, say a bit above 10'000 meter. At altitude the dry thrust of the engine degrades quite a lot because of the thinner air, but wet thrust is not reduced that much. Therefore the real difference in thrust is much bigger than the official static numbers.
Also the higher outlet speed at wet thrust makes the engine much more capable at high speed, while the lower outlet velocity in dry degrades thrust quite quickly at higher speed. Especially the thrust from the fan is pretty useless near M1 and all in all wet and dry thrust can't be compared. There is a reason the on paper just slightly more powerful thrust at afterburner can produce so much higher speed."
No it is not.
It can be very significant and largely depends how missiles are arranged. The Eurofighter solution is well thought, most Eurofighter performance figures are based on 4 MR-AAM and 2 SR-AAM.
The Suchoi carries the missiles in a rather drag prone configuration. I wonder why nobody though of remedying this issue with semi-recessed missiles.
On the topic: I think the Suchoi 35 will have a number of superior flight performance figures. But I further think that those will not translate into a better exchange ratio under real life conditions. In a frontal engagement, most (=50% and more) Suchoi 35 will be down before they get in visual range.
Publicly, we say one thing... Actually, we do another.
Get real. See the specs.
Well, maybe because there is no need to?Maybe because they thought about it from day 1 when designing the airframe? Do you thinks the Russkies don't understand the basics of aerodynamics anymore?
In VISUAL range? against modern fighers? Of course 50% will. And it's a very good figure at that, actually. The problem is that fighter pilots are rarely willing kamikaze and usually would prefer to carry missiles on their Su-35 and not just guns.
Dear DJC,
You are arguably amongst the best posters on this forum (and one of few reasons why people like me visit it), and hence it saddens me when you let your liking for the national side overwhelm what you already know because people just bait F-22 or JSF because American patriots overhype it. We know what it is, we dont need person like you to defend it. You are above it.
Did not I say that Su-27 can have RCS much more and even then you can do 4th square law calculation and determine the performance for much smaller RCS?
When you do so, you can see with an increase by 4 times in average power, it is possible for Irbis E to get range equal to what it states.
That is what I was saying.
Bars, please be aware has been tagged by your own Red Flag exercise as a threat. When it was operating in training mode. When it was facing ECM.
Irbis-E is APG-77 without the fancy pulse-to-pulse modulation. It is brutal old style Russian approach.
American engineers beat it a long time back and that is why Israel took the new X Band US radar in Negev desert if my memory does not fail me.Tomb Stone and its new sibling Grave Stone are the best X-band tracking and engagement radars in production today (It's what :diablo: evil American RCS engineers strive to beat) and has range that exceeds Irbis by >30% due to size of aperture and radiated power.
Tomb Stone and other GBAD also operate in many other modes, and their range is also understated, and being mobile radars on TELs they are not large scale AESAs with the power available (hence performance).
I will say one more thing, Russia has bragged about Irbis because it is export capable - have they bragged about PAK-FA radar? Why not? You know it much more than I do, given your valuable knowledge base.
I will only say this. The JSF does not need someone of your caliber to defend it. The US's leading edge in avionics and netcentricity will make sure that the plane, even if it is middling aerodynamically, that it will perform versus isolated threats which can never manage the kind of support the US assembles, from Rivet Joints to AWACS.
Best regards.
Last edited by Defexpo; 21st November 2008 at 19:08.
Dear LMRaptor,
What is the point of your post? It is something everyone knows!
I mean it is fairly useless.
If someone uses APG-80 figures from Raytheon, then fairs fair, in using what NIIP says about their radars, trying the best to determine respective national differences (1 mtr sq vs 3, nm vs km etc).
Your post just reads as "sour grapes" about other posts about Irbis-E et al. IE you dont have anything valid to state, so all you can do is crib "we do not have enough data". Well, gee - we dont have ANY proof about APG-77 as well.
Please, such semantics are childish.
Dear Wrightwring,
which is wrong.
Besides, reading helps. Please read his earlier posts as well about his estimate of Irbis-E range. It is way incorrect.
Incorrect. The Bars is much superior to Irbis according to reports. The Irbis is much superior to Bars. While this does NOT mean the Irbis can lock onto F-22A. It does means your train of though is a non sequitur.If APG-63 couldn't lock an F-22 at visual ID range, the Irbis will be a little better, but not significantly better."
They would be comparable to Bars.The AESA models have greatly improved performance though.
Yes your post is a lot of nonsense. A lot of pseudoscience and confabulation. Science taken out of context because of your lack of knowledge or because you are wishing to advance an agenda (a confabulation).
My and my acquaintance assertion that the F-16 has plenty of thrust, is not necessarily a Mach 2 reference, it is pointing out that the limiting factor on the F-16 may have other factors involved such as overheating from thermodynamics when the aircraft is empty; understandably when aircraft is fully loaded and has high drag there may be thrust limitations. You seem to have mental tunnel vision/fixation.
Your sea level specifications seem to be just a red herring to derail the debate; we are talking about flying, not driving. We of course were not talking about sea level.
Source http://www.f-16.net/f-16_versions_article25.htmlOriginally Posted by f-16.net
Agreed; his posts prove that. His attacks is apparently based on his own insecurities; his attempts to bluff and bully only make a fool of himself.
It’s obvious that he was responding to you because you are trashing/bullying trying to bluff your way and or because you apparently don’t understand what you are posting or what djcross is posting. In your apparent attempt to bully and bluff; you demonstrate your own ignorance. It seems you still don’t understand what he’s talking about or and you’re a troll trying to filibuster, bully and or bluff.
The above two quotes were posts by you (Rogerout) were in response to djcross's quote below.
I feel that if you (Rogerout) understood as much about turbofans as djcross; you would understand how it’s related. I’m not sure if I know as much as djcross in the technical aspect; but even with my poor language skills I understand he makes more sense; whereas you seem to be more rhetoric ( pseudoscience/out of context.jargon)
To assume that the JSF and F-16 cannot super cruise, or exceed Mach 2; proves that you ignore the facts and don’t have as good of an understanding of jet engines as you claim/pretend/think.
Last edited by ATFS_Crash; 21st November 2008 at 20:03.
Actually, I find F-35 satisfactory as a Harrier replacement, but sorely lacking for USAF and CVN use.
For USAF, it forces restrictive basing and deployment requirements that any potential adversary who paid attention during Desert Shield and OIF knows how to counter.
For USN, F-35 still lacks the range needed to do anything more than support the USMC in littoral conflicts.
The F-35 program appears to be built around the notion that every bar stool in the Officer's Club has to remain occupied over the long term. The number of flight hours required to maintain pilot proficiency makes the F-35 program unaffordable (that's about 95% of all hours flown and 95% of the operations and support cost). Pilots are poor sensor suites and make too many mistakes. Pilots force the designer to add heavy, expensive life support equipment and severely limits airplane performance. The posters who mentioned UCAVs in the Norwegian JSF thread are spot on.
It wasn't my train of thought first of all, so there were no non sequiturs. I was correcting a misquote(the correct quote was what I posted above- the misquote was that the Irbis had 80% of the APG-63's range). I think the point being made is that if an APG-63 can't spot you at visual range, then it'll be challenging for Bars/Irbis to do as well.
Good God man. HOW is being able to carry MORE fuel internally than remotely comparable 4th generation fighters with THREE external tanks PLUS A SIMILAR TYPICAL COMBAT LOAD of two MRAAM & two precision guided munitions (or eight 250 lb SDB) an "Achilles' heel" or "massive limititation" or a "great problem" for the F-35?
DO YOU NOT REALIZE THAT IT IS ONLY ABOUT THE SIZE OF A RAFALE RATHER THAN A FLANKER? The F-35 is NOT a medium bomber!
Again, HOW is it problematic to carry MORE fuel plus a SIMILAR combat load to what is commonly carried by other 'similar' fighters?
Where have I EVER said that the Su-35BM has 'many' weaknesses?
Dear Wright, would you kindly stop "interepreting" DJC's thoughts for him (btw, his last post is making me think a lot, but thats the way he is, valuable and packed full of info, when he hits the home run!!).
You are again not reading what I wrote, and what I was referring to. I addressed the specific points, and I also made it clear about what Irbis-E/Bars will face in terms of challenge.
Your continuing to argue in circles; because you fail to comprehend or acknowledge the full extent of what I’m saying.
What you perceive as an advantage for the Su-35 and disadvantage for the JSF; will most likely and most often be on the contrary; an advantage for the JSF and a disadvantage for the Su-35.
As has been said many times but has fallen on deaf ears and hard heads. It doesn’t have to carry weapons internally; it has external hard points. When it carries its weapons internally it has a greater degree of stealth. Even if it carries weapons externally; it would still be more stealthy than the Su-35 with an equivalent load out. Therefore legacy aircraft like the Su-35 is more likely to be fodder and it and its weapons are more likely to become losses. As others have already pointed out; the JSF already by default carry a lot of things internally that legacy aircraft had to carry on hard points; so even if the JSF has less hard points or uses less hard points; that is largely because it doesn’t need them as much. Often hard points are used up by such things as fuel, jammers, targeting pods, etc….; with the JSF there will be less need to use an hard points in that fashion, so it frees up more hard points for weapons.
For the benefit of the others.
Supersonic speed is the result of the inlet and outlet-system.
At Mach 2+ it is 63% of thrust, what is generated by the inlet and 29% by the outlet, when the engine is down to 8% or just keep it running.
Be it the F-111, F-14A or the MiG-25 to give some prominent examples about that and their moderate installed thrust values.
Fix the inlet-system and your former Mach 2+ fighter is down like the F-14D, B-1B or MiG-27 and Su-24 to give some prominent examples.
I wasn't interpreting what he said. I was correcting your misquote. If you look back to page 4 response #104, he said-
"APG-63 has about 80% of the claimed range of Irbis-E. If APG-63 couldn't lock an F-22 at visual ID range, the Irbis will be a little better, but not significantly better."
Then I reiterated what he said-(notice the theme)
"I think the point being made is that if an APG-63 can't spot you at visual range, then it'll be challenging for Bars/Irbis to do as well."![]()
Inlet ramps/cones don’t give much benefit until above Mach 2. Going supersonic is counterproductive for a stealth aircraft; because the sonic boom can give away its location acoustically and on radar and IR. The shock wave on the SR-71 was so powerful that it could be seen on radar hundreds of miles away with conventional radar of the era. I would think that most of the time that the F-22 and JSF are being used that they would be subsonic; unless it’s scrambling to an impending urgent threat or trying to search an unreasonably large area.
Like Chuck Yeager said “inlet ramps are not worth their cost and weight in most cases” I think he was talking about inlet ramps on the F-4 Phantom II. He said something to the effect, that was his opinion that the cost, complexity and weight added to the aircraft was hardly worth the slight gain of speed. I think he said this about the time of the Vietnam war, at that time there was about a 20% loss of thrust using fixed inlets at Mach 2.
Last edited by ATFS_Crash; 21st November 2008 at 21:19.
Depends on the engine.
Generally Chuck Yeager is right, when speeds above M1.8 are not the target.
No one knows what were the specs at that time. But for prolonged cruise at M1+ to M1.5 the idea to carry missiles suspended on pylons is crappy. You should understand that for any aircraft the design goal was M1.5+, and nobody asked for performance at M1.3 as long as the aircraft came through it. For supercruise performance you have to think exactly about that and you'll come to semi-recessed missiles.Originally Posted by RSM55
Publicly, we say one thing... Actually, we do another.
The metric used to assess radar performance in the US is Pcum90 (probability density function that gives a 90% probability of detecting the target) for a 1 sqm target. But RCS engineers often use Pcum50 (50% probability of being detected) as a metric of the effectiveness of stealth features. Lots of factors effect the probability density function, such as radiated power, range, gain, scan rate, clutter, reflectance, incidence and atmospherics for some frequencies.
When comparing Irbis, Bars, APG-77, Flap Lid, Sampson, Etc., the person performing the comparison needs to assure the same metric is used. For example, Irbis or Bars may claim great detection range, but upon closer examination you might determine the they were stating cued search rather than max volume search. By using cued search, the scan rate within a small (cued) sector may be an order of magnitude greater than it would be in a max volume search. Of course, the cued search range looks great in a sales brochure, but isn't representative of how the radar will be used for 99% of its lifespan.
So true. So often people try to compare to dissimilar figures as if they are the same. Which is misleading at best; sometimes it is naivety/ignorance but often I can’t help but feel there is some deliberate dishonesty/con.
Such as
US TWS compared to Soviet RWS
Or
US Look down range, to Soviet level first detect range
Or
(different sized targets)
US 5 m² target TWS range, to Soviet 25 m² target RWS range
Last edited by ATFS_Crash; 22nd November 2008 at 00:41.
Seriously dont know who did start that "for the day 1 you wont need the full load weapon" tale, but it seems a recent tale...to hide the obvious shortcoming of the 35's lack of weapon load
Well, is the day 1, the day that you need more weapons than ever...and since the f-35 is so into the "day 1" thinking, i find a bit funny it low internal weapon load
For the day one the Raptors for sure will need more than 6 miserable missiles, and external fuel tanks....at least for the day 1 the flanker (and i think the F-35) can avoid external fuel tanks...
I mean the practical RCS has a lot to do with the practical plane's requirements
PPl, still claim about that aussi pilot, but im sure that if the f-22 wouldnt be able to be locked-on on visual range (and knowing how the USAF/Industry are so willing to show how cool is their aircraft) we should be drowing on a sea of nice HUD pics without the lock-on sign...instead of that we have a lucky leak...with a lock-on...and that aussi pilot tale
Last edited by over G; 22nd November 2008 at 13:01.
"It won't let me put a weapons system on it, even when I can see it visually through the canopy. annoys the hell out of me."
-Best joke ever
Reuters "clubs F-22 like baby seals":
Balls!!? (but not golf balls, apparentlyU.S. fighter plane needs major upgrades-arms buyer
WASHINGTON, Nov 20 (Reuters) - The U.S. Air Force fleet of F-22 Raptors, designed to be the world's top fighter jet, needs more than $8 billion dollars of upgrades to be made "capable and affordable to operate," the Pentagon's top arms buyer said on Thursday.
The comments by John Young, the undersecretary of defense for acquisition, highlighted Pentagon opposition to buying more than the 183 F-22s on order from Lockheed Martin Corp (LMT.N: Quote, Profile, Research, Stock Buzz), the prime contractor.
The Air Force long has argued it needs 381 F-22s to be able to dominate the skies at the start of any major war and clear the way for other U.S. and allied warplanes.
Young said the Air Force already had budgeted about $8.3 billion for software upgrades and unspecified modifications to about 100 of the F-22s that would otherwise "kind of be lesser models."
Those outlays should be taken into account before talking about buying more jets, he told reporters at a breakfast.
"I don't think the debate is informed by all those facts," he added.
In addition, the F-22's "mission capable rate," a measure of its readiness, fell in the 62 percent range in the 2008 fiscal year, Young said.
"I think that's troubling," he went on, adding the fighter, which features advanced technology to reduce detection by radar, "is proving very expensive to operate."
Christopher Bolkcom, an expert on warplanes at the Congressional Research Service, said the mission capable rate was an incomplete gauge of an aircraft's availability.
"As a rule of thumb, however, 62 percent is unsatisfactory," he said.
Young said there were also struggles with low-observability and other issues that he did not name.
"Clearly, (there's) work to be done there to make that airplane both capable and affordable to operate," he said.
The F-22 had failed to meet most of its "key performance parameters" in operational tests last year and the trend was negative. Maintenance manpower hours per flying hour had gone up since previous tests, with the last one a "substantial" increase, he said.
Lockheed Martin, which has delivered 131 F-22s to the Air Force, declined to comment on Young's remarks, referring calls to the Air Force, which did not immediately respond.
The Pentagon last week released $50 million in bridge funds to preserve a decision on future F-22 production for the incoming administration of President-elect Barack Obama.
The production line must start shutting down early next year unless Obama opts to buy another batch.
Lockheed produces the F-22 aircraft in partnership with Boeing Co (BA.N: Quote, Profile, Research, Stock Buzz) and United Technologies Corp's (UTX.N: Quote, Profile, Research, Stock Buzz) Pratt & Whitney, which builds its dual F-119 engines.
In June, Gates ousted the Air Force's top military and civilian leaders amid a tug-of-war over funds for the F-22, which he considers ill-suited for post-Cold War conflicts such as Iraq and Afghanistan. (Reporting by Jim Wolf; Editing by Andre Grenon)
© Thomson Reuters 2008 All rights reserved
).
Dear wright, you seem to have a problem with reading things in context, bolded messages apart and claims of misquote apart. I did not misquote anything DJC said, and I was correcting the basis on which DJC made the statement above. Which apparently you do not even understand but are rushing to reply, again and again and again.
DJC made the statement that the APG-63 has 80% of the range of the Irbis-E and on that basis said Irbis/Bars will have same problem as APG-63 - the Irbis is substantially more powerful and is actually in the class of the APG-77 (non LPI full mode). So to state that the Bars and Irbis will have the same problem of visual range lockon, based on the above assumption would be wrong.
Simply put there is no data on this aspect and will not be until the situation occurs. There can be estimates however, that the F-22A should be good enough to avoid lockon at long BVR ranges, for now, from existing legacy radar sets. Extrapolating that to radar performance within WVR from sets which differ substantially in performance is unwise.
Hope you understand this time.
A-In post #129
you said-
"Dear LmRaptor, reread what Djcross wrote. You misquote the exact point I was addressing.
He said that it was not possible for the Irbis to detect (lets even leave discussion of what mode the Russians are talking about) a 3Sq Mtr fighter target at 350-400 km, citing a totally different GBAD component as proof. Second, he said the Irbis E range is 80% of the APG-63"
I corrected you.
B-No one is disputing that the Bars/Irbis have greater capability than early APG-63s. The point is that at that range their advantages aren't going to be significantly better. What's important here is that there isn't much return for even a powerful A/A radar to pick up.
I think you have a problem with reading comprehension in this specific case.
DJC first said that the Irbis could not detect a target at 350-400 km.
Post Number #92.
Then he made the above post about RAAF pilot unable to lock on in WVR. Based on his earlier assumption about Irbis range, he stated that the APG-63 was 80% of the range of the Irbis.
I addressed both points.
1. That the Irbis range was possible and in fact logically consistent given Bars performance (Irbis heritage)
2. Given Irbis/Bars superiority to APG-63 MSA, assuming the same limitations from them would be incorrect (ie non lock on in WVR).
Hence there was nothing to be corrected.
Instead you are going on and on without understanding the basics of what the contextual discussion was and repeating the same old song without any merit.
You still dont get the point either.
Unless you know the exact signal processing & operational behaviour of the Irbis/Bars saying there wont be enough return for them to lock on at WVR, is an assumption without merit. Just because an inferior/earlier radar, based on a different design basis, from a different country, from a different manufacturer, using different DSP and focusing techniques, and part of an entirely different WCS, was not able to achive the result does not mean the Irbis and Bars will fail similarly.
Now kindly, please dont say the same thing over and over again.
It is like having the "badger badger" song played at full volume.
Last edited by Defexpo; 22nd November 2008 at 18:00.
A- You and I weren't discussing the Irbis' 350-400km detection range. We were however discussing you misquoting the Irbis only having 80% of the detection range of the APG-63
B- The RAAF pilot said he couldn't even detect the F-22, much less get a lock on, so the fact that the APG-63 was MSA is immaterial.
C- The APG-63(v)1 has parity with Bars, though it's inferior to Irbis. Bars wasn't being discussed though- it was that the APG-63 had 80% of the Irbis' detection range.
D- You still refuse to acknowledge having misquoted DJC, even though I've clearly shown which post, and the actual text.
E- It's true that I don't know the processing power of the Bars/Irbis. You don't know the processing power that the APG-63 has either, so it's a bit disengenuous to use that as the basis of your argument. At point blank range, the advantages that the Irbis has aren't going to play as big of a role, as they might at 400km.
F- I'm not the one that refuses to acknowledge that I misquoted someone, so....if you don't want me to keep repeating myself, you could start by saying- I was wrong.![]()
What day one do you have in mind?
Your intelligence people will tell you that some sort of danger is building up. You political leadership will decide how to respond to that.
When the military solution is choosen to deal with that, there are two options left. Waiting for that attack or do attack yourself. Whatever is choosen, the military will use the time left to reach the combat level in need.
The prime concern is to bring your intelligence data up to date. Where are the prime targets of your opponent to find at attack-time. What weaponary is at hand and brought to bear in a coordinated way. The times are gone, when a whole squadron was tasked to detroy a single target. The first targets of every conflict are the "net-work" items like command- and communication centers and the prime sensors to fed that. When the opponent is weakened to behave in a coordinated way any longer, the next step is to win air superiorty of an area of intrest.
After the first night in the Iraq war, that country was defeated by cold military logic already. The allied forces had flown a surplus in missions, which were not in need really. The problem of modern air-forces is not the lack of numbers, but the lack of intelligence info for usefull missions.![]()
Last edited by Sens; 22nd November 2008 at 20:54.
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