crobatoNew AESAs at this point should be considered more like version 1.x if you use the software industry norm. To get to version 2, we have to leave the current GaAs compound behind and use GaN.
The first generation is not really big per se, but genuinely power hungry and worst off, massive heat generators. While the radar itself is not heavy, higher power requirements means bigger transformers, and you cannot save weight on that due to the iron cores that are needed. In addition, you now need to factor increased capacity cooling systems, which in turn needs more power and so on, adding to the transformer and generator requirements.
So you really need to reduce power requirement and heat generation in the future.
crobatoHi crobato, do you have infos what made that (J-7III) unpopular with PLAAF pilots?
One weak point of the R-11 engine was its long spool-up-time, what became dangerous at low level flight, the other problems from the maturing engine aside.
Some of these are shared with the MiG-21MF and -Bis.
-High wing loading which meant long takeoffs and landings, and riskier landings requiring higher speeds.
-Low speed handling is not very good.
-Poor visibility from the cockpit. The spine and the larger nose does not help.
-Problems with the radar. Though solved in the J-7D, the stigma remains. It is quite interesting that the J-7C/D radar is quite different from the MiG-21MF. The former uses a helically scanning parabolic array much more similar to Western fighters in the Vietnam era, while the latter uses a conically scanning flat circular array.
-Being out turned by the J-6s. But then, so did the earlier J-7s. The J-7/MiG-21 generally has better ITRs and roll rates over the J-6/MiG-19, but the latter has better STRs.
-The planes (all J-7s and MiG-21s) are difficult to recover once they stall and depart from controllability. It becomes a double whammy if you have higher wing loadings which means your stall point can come in earlier at a higher speed.
crobatoI’ve heard this a number of times now, but i still don’t get it how they get the necessarily larger airflow the R13 (or even R25) needs out of the narrow MiG-21F-style intake. Sure, the F-based J-7s lack the large spine (which actually housed dead-weight of unusuable fuel in case of the MiG-21SMT) but the latter J-7s have the larger, heavier wing.
They have very narrow intakes also for the J-8II and that was supposed to work even in higher altitudes with less dense air. At lower altitudes, the denser air should not be a problem for the J-7 where it is primarily intended to operate.
Airframe/engine-wise, the J-7 is IMHO more of a single-seat MiG-21UM then it is a narrow-intake MiG-21MF. And there’s quite a bit of difference in performance because of the smaller intake in the UM.
It would probably only matter near maximum speed, but then Fishbeds would have run out of fuel before that.
crobatoThe YF-19 from
Macross plus
http://www.youtube.com/watch?v=uhBhqQ9Mxz0
Its pretty ironic Japanese can design badass jet fighters in fantasy but can’t design them in reality 😀
The ones from a more recent anime, Yukikaze, look a lot better. The ones in Macross morphs into mechs, but Yukikaze deals strictly with aviation and aerial combat, no morphing mechs here. Because of the gorgeous fight and flight sequences, this is an anime I would recommend to any aviation fan.
crobatoSo USA (if ever) would sell Raptor at about 150 M$ (maybe) to Japan. And maybe japanese have calculated that it worth to construct their own stealth jet.
In the long run, its like the case with India, trying to develop your own fighter is far more than the issue of national security, its the opportunity to flex and develop your own national technological muscles. Buying F-22s won’t help this, unless you consider this an opportunity for the Japanese to study the F-22 and apply the lessons to make their own 5th gen fighter, not to mention the technologies can be dual use and apply to other areas that would end up competing with US products. That’s probably one of the objections the Pentagon may have considered.
They already have an AESA radar (although not so good maybe) and we should no doubt their abilities to make all the necessary electronic equipment.
Having made their mistakes, they are in a pretty good position to design a 2nd generation AESA. They don’t seem to consider the current F-2 radar worth moving beyond than merely fixing the glitches and possibly adding one or two more capabilities to it. Which means they probably think its time to leave that now behind and work on a new one from a clean sheet of paper.
crobatoAnd how would the Russians have arrived at these concepts later?:confused:
It was only because of many years’ hard won experience in the Vietnam War that forced the Americans to think seriously about the nature and future of aerial warfare including a-to-a combat.
This serious “thinking” led to far more WVR capable aircraft such as the F-15/16/18 – but never the less, the Americans still laid primary stress in BVR techniques which may be why they found the Sidewinder’s replacement, the ‘AIM-95’ too expensive and didn’t bother with it, while expending great resources on BVR missiles, improved AIM-7s, AIM-120 etc…
The Soviets, on the other hand, have had very little experience of “aircraft on aircraft” combat, apart from the odd South Korean airliner, and they don’t seem to have developed a great body of theory to fall back on. There are half a dozen or more countries in the world who had gained more modern air combat experience during the Cold War than the Soviets did.
Certainly most of their combat aircraft seem to be designed to conform to any great aerial warfare theories, but instead seem to be designed with the singular purpose of being able to take on particular NATO aircraft types: MiG-25 v A-12/B-70, MiG-23 v F-4…
Well they were in the first place, first hand observers in the Vietnam thing. This despite they were already running a course away from dogfighting with sizable momentum (leading to the MiG-23).
But of course, the Russian equivalent of dogfighting would also color their own theories. Still predominant in Russian theories is the turn rate, although the Americans were favoring roll rates. Another is the emphasis for high angle of attacks, small turn radius and low speed maneuverbility, as well as the ability to suddenly bleed energy which can cause an attacker to easily overshoot—generally Russian fighters have much bigger (and effective) air brakes than US fighters.
crobatoI believe its something from Macross.
crobatoThe whole work is said to remain confidential. Nonetheless it looks like the Russians, and everyone else, would have arrived to these concepts sooner or later.
In the mid sixties, you can take any USAF and USN aircraft, even an F-4 Phantom, have it go into a dogfight with an F-86H, and end up in the losing end. The F-86H is often used to simulate a MiG-17.
crobatoSounds like they’re doing this in the hope it will force the United States to review it’s ban on selling the F-22.
Perhaps, but I have a feeling that this idea has been going around much longer than that, and the reasons are far more profound. A country with the technological capability and pride like Japan is not going to sit around and be content playing second string. A true indigenous fighter is still something of a national dream and ambition, and it is the current thing that is still lacking. Japan already has indigenously designed tanks, subs and ships, why not a fighter, and rehashed F-16s do not apply. I won’t be surprised they have been working on this conceptually and perhaps did some preliminary work in secret right under our noses.
crobatoActually, when they’re starting to seriously consider the Eurofighter, or building one of their own, that means the possibility that the US will deny the F-22 to them is very real and they are already accounting for it. They may not politically accept the JSF or a nerfed export certified F-22 which is what LM has been proposing, due to national pride.
crobatoThe GDR-pilots revealed, that the three main variants of the MiG-21s behaved differently. Verified by testing after unification. No surprise really by constant rising wing-load. The loss of agility was traded for gains as a weapon-system.
The dry thrust level (~40 kN) did not grow in a similar way like the AB thrust (up to 70 kN) to keep the t-w-ratio, because there were no noticeable gains in sfc. The basic J-7 is a MiG-21F or Fishbed C from the 50s. The controls of that variant did harden above Mach 0,9 in dense air. So the limit of ~620 kt at s.l. or below Mach 1. In the thinner air high up there was no limitation.
From a handbook in GDR service the F-13 had a top speed clean of 2150 km/h above 12000 metre, when below it was restricted to 1200 km/h. With external load it was 1680 km/h and 1000 km/h below 12000 metre.
The PF or Fishbed D showed silimar limitations. 2175 km/h clean in 12500 metre, in 2000 -12500 metre 1200 km/h and 1150 km/h below 2000 metre.
The stepped variable intake cone settings used on the MiG-21 can be a factor in limiting how the optimization of airflow to the engine. As you know, the early MiG-21s only had a 3 settings or steps for the intake cone. The J-7s on the other hand, after the initial model, went to a continous no step variable cone. Furthermore they started tweaking the engine ratings. The J-7E is a hotrod, essentially taking the more powerful engine of the MiG-21MF and slapping it into the lighter MiG-21F airframe.
As you know, the J-7s skipped the 2nd MiG-21 generation and went to the 3rd generation directly by copying the MiG-21MF. That became the J-7C and D models. They however, proved to be unpopular with the PLAAF pilots, and the next version went back to using the first generation airframe. The J-7C/D, roughly around estimated forty to fifty built total, are still in service today with some reserve fighter group. You can probably and accurately guess the reasons for the plane’s unpopularity from other people’s experiences with the MiG-21s of this and later generation.
crobatoEveryone is interested in stealth. This kind of news however suggests that the US selling F-22s to Japan seems to get less likely with every article, and yet Japan is not interested to acquire the F-35. So, they are going to do something on their own that fits their requirements.
crobatohttp://www.defensenews.com/story.php?F=2920007&C=asiapac
Posted 07/24/07 09:19
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Report: Japan to Design Stealth Jet
AGENCE FRANCE-PRESSE, TOKYO
Japan’s defense ministry hopes to make a prototype of a next-generation stealth plane, the first new fighter jet designed by the officially pacifist country in 30 years, a report said July 24.
The ministry will include funds to develop the manned prototype in its budgetary request for the fiscal year from April 2008, the Yomiuri Shimbun daily cited anonymous defense ministry officials as saying.
Japan has been officially pacifist since its defeat in World War II but has one of the world’s largest defense budgets and has gradually been expanding its military role.
The defense ministry is hoping to keep its technology up to date and also gain an edge in negotiations with the United States when it selects new fighter jets, the best-selling newspaper said.
A defense ministry spokesman denied it had made the budgetary request but said it had not ruled it out either.
“But we have been studying stealth and other capabilities,” the spokesman said. “We are also working on a plan to study small aircraft. We will continue to work on these tasks.”
Japan has indicated it wants to buy F-22 Raptors, the latest U.S. Air Force jets built to evade radar detection at supersonic speeds.
U.S. law prohibits export of Raptors. But the United States flew Raptors to Japan earlier this year on their first foreign flight, showing its commitment to the two countries’ security alliance amid tensions with North Korea.
Japan and the United States already jointly design F-2 support fighters, but production is set to end in March 2012.
The Japanese government has not supported development of a domestic fighter aircraft since the F-1 support fighter jet in the 1970s.
F-15 fighter jets, which form the core of Japan’s fighter force, are being manufactured here under a license agreement with the United States.
The Yomiuri said development of Japan’s new prototype would likely cost hundreds of millions of dollars over 10 years.
The design would not include installing weapons and it is unclear whether Japan would actually produce the prototype due to the huge cost of building a full aircraft, it said.
crobatoI see your point, but it is the brute force of the F-4 and the higher momentum, what gives it the edge over that mentioned fighters depending on speed.
Maybe it is the pliot and/or the tactical situation, what makes the difference really, because all that are flown by stick and rudders.
The F-4 is “big” target, but user friendly and with four experienced eyes and two brains are difficult to beat in a multi-tasking enviroment most of the time.
By the way, do the present Chinese examples have overcome the shortcomings in the transsonic-range, which handicapped the Russian examples till the Ms? The quoted max s.l. speed is still given ~ Mach 1 only!
Just personal intrest, maybe you have first hand infos from a J-7 driver.
A Romanian Lancer C variant will beat a F-4D from the 60s with ease, thanks to the superior weapon-system. Just to remember that comparisions are limited to a given time.
I don’t recall or hearing J-7s having transonic problems, and if it did it was news to me. The maximum quoted speed is well above Mach 1. Reports of flight behavior has been generally favorable. The most notable vice of the J-7 lies in another area; when it spins after it stalls it is very hard to recover. Perhaps you meant J-6?
TWR gets fairly high from the MiG-21MF above, to the -bis.
Another aircraft that does very well with rolls or maneuvers involving rolls is the Mirage III.
MiG-17 is the MiG that one typically identifies with very good horizontal turning ability (the MiG-21 does not really turn that well horizontally) but gets a little weak on the rate of roll and does not have the power to hold with a brute like the F-4. Thus when confronted with this sweep wing fighter, one would expect the F-4 driver to end up using barrel rolls, rolling scissors, and yoyos. Same trick however may not work as well on the MiG-21 something of note since some people transpose the flight behavior of earlier MiGs like the MiG-17 and MiG-19 to the MiG-21 when in fact, their flight behaviors are quite different from each other.
crobatoI don’t think so… considering the poitical implications involved if such a ship was ever detected. Japan simply does not have the same creditability as everyone else is Asia. For any japanese politicians it would mean career suicide.
Plus its a SSK and given the fact that it CAN NOT remained submerged puts this theory to doubt.
Can certainly lead to embarrassment. One time the ROCN Orion detected a sub sneaking into one of their exercises. The automatic assumption that it was a Han class sub. But no wait, turns out the acoustic signature was something else. When verified, the result was an embarrassment for Washington. It turned out to be an LA class sub, and it was trying to snatch a spent ROCAF MICA missile underwater.
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