crobatoThere is nothing special about a very wide off boresight. That’s usually achieved by a gimballing seeker (rotates on a ball joint) rather than a fixed one, then putting the seeker in a semihemispherical front lens. No matter how good the electronics of your seeker is, if it’s fixed, you can’t have more than 45 degrees off bore (90 degrees FOV). Another limiting factor is the extent which the aircraft radar can gimball by itself to track the target and que the seeker. Theoritically, if the parent radar has a smaller FOV than the missile’s own seeker FOV, your effective FOV would follow the radar’s.
I take it the R-73E is 45 degrees without the HMS, 60 degrees with the helmet. The R-73E appears to correspond to what was previously known as the R-73M1 (that with the optimistic 30km range, which the R-73E also reflected) rather than the R-73M2 (that with the optimistic 40km range) which was redesignated K-74.
To get the missile seeker to gimbal to 60 degress, or even 90 degree off bore, you would need a helmet sight to que it that far.
With regards to the PYthon 3, or at least the Chinese copy of it, the PL-8, the Chinese appeared to have modded the seeker on the later blocks of the missile, probably at least 60 degrees since they appear to be using them now with helmet sights (60 degs were mentioned in PL-9 brochures in airshows). Perhaps without helmet sight, the missile should have a 40 to 45 degrees OFB. They probably studied the R-73 closely (they gots tons of them) and adapted the techs to the PL-8. It is also probable that Python 4 techs were indeed leaked to the Chinese, so that the missiles could be using Python 4 techs on a Python 3 body (a Python 3.5?)
It is odd that the Israelis preferred not to use TVC, kept using the draggy but highly maneuverable layout using large control surfaces.
It should be noted that the R-73 is a relatively slower missile, Mach 2.2, but should get better range. The Python series are faster, Mach 3, but with shorter burn motors, sacrificing range and endurance for a quicker kill.
OFB is an overblown issue. PK rates actually fall the further you shoot the missile offbore since you waste a lot of energy when your missile goes sideways. Pilots are trained as much as possible to use their missiles as much as within directly boresight of their plane to increase kill chances. Once you reach the 45 to 60 degree region, what really should be more important now would be flare discrimination, and there is always room for more efficient rocket propellants. I have not heard much about the R-73’s flare discrimnation qualities (I heard some not so encouraging stories but they could be biased), while the Python 4/5 have great emphasis on this issue. Python 5 appears to still use an analog seeker, the explanation the Israelis gave is that you’re going to need an extensive database of thermal images if you’re going to use a digital IIR seeker, and that won’t be possible without some super espionage effort.
crobatoHi GDL,
They already got those launcher tubes installed on the 052C, and they’re clearly not the squared launchers for the C-803. They’re certainly much bigger, round with ribs. Suffice to say, they should encase a new indigenous AshM that we have not seen so far. Oddly enough, like the Sunburn and the C-803s, these new AshMs are working in conjunction with the Bandstand radar installed on those destroyers (or are they just Bandstand like or Bandstand copy-clone but are indigenous?) I wonder if there are any Lightbulb datalinks on the 052C. Must be—I should look at the ships closely.
Some speculators even say that these AshMs may be YJ-84 (C-804), perhaps like the C-803 but with an even longer range. My highly speculative opinion is that it’s a supersonic AshM in the same performance class. size and weight as the Oniks.
crobatoI’m quite confused by the picture too.
crobatoGrumman’s work on the Super-7 was primarily intended to create an upgraded J-7, much like the modernized MiG-21s you see in the market now (-UPG, Lancer, -2000). The F-7MF or J-7FS is more like in the original spirit of that project. FC-1 is S-7 only by name—somehow all previous work is discarded and the plane is an all new one. FC-1 was only probably a serious project very late, with much of the development work concentrated in the late nineties to early 2000s. I think back then in the late eighties, all Grumman could do is just toss around a few drawings of a proposal—and with or without Tianammen, the project is doomed to failure like the Peace Pearl project. The Chinese could not probably tolerate the inevitable American style defense project cost overruns. Except for the engine, the FC-1 definitely indigenous.
More intriguing is the question whether the T-50 or the F-CK-1 is indigenous. There seems to be a lot of American input in those planes.
crobatoChina has been making turbojets and turbofans for missiles, and its been doing it for a long time now. The YJ-82 (C-802) has been flying with a turbojet or turbofan since the mid nineties. Prior to that the Chinese also have the Kraken (C-601 or YJ-61) which basically amounts to a Seersucker airframe fitted with a turbojet. There is also a newer development called the YJ-62.
The Kraken itself is a pretty long ranged missile, up to 200km by some accounts. The C-802 is only 120km from a surface to surface profile, but air launched versions can naturally go further for obvious reasons, being launched from a height and the parent plane speed’s added to the missile. The C-803 (YJ-63) is said to be 160km, which is probably from ship to ship, but air launched it could go further. The US military disclosed a C-803 launching from a JH-7 with a distance of 255km.
I don’t think the C-803 is supersonic not by any means. It’s still a subsonic sea skimmer like the C-802 which it evolves from. The nose isn’t sharp enough for supersonic use. Furthermore, it clearly uses a datalink, which indicates the missile is intended well beyond horizon use, but it isn’t fast enough to prevent a ship from going beyond the seeker acquisition envelope by the time the missile gets there over the distance using pure inertial navigational guidance.
The new undisclosed AshM on the DDG 170/171 “Red Aegis”, only seen on launcher tubes, may be supersonic however.
crobatoYou probably believe the US knew that the 9/11 attack was coming too.
Funny how the many clues leading to 9/11 are not considered “actionable intelligence”, including a previous outright bombing in the parking lot of the World Trade Center. While false clues on Iraqi WMDs are.
But let’s go back to Pearl Harbor. The moment the US embargoed Japan on valuable raw materials for invading China, built a big and capable navy and airforce, and when Japan signed treaties with Nazi Germany already at war with Great Britain, along with the act of invading China itself for territory and resources, you have to be a complete dimwit to assume you’re not going to fight this.
crobatoYes, I’m refering to enemy position update, or maybe commands given by the parent radar to ‘guide’ the missile to its target.
crobatoThere is no difference between emissions and echoes save for the doppler effect. In fact, every missile reaches some point in its path where the emissions and the echoes are exactly the same.
Imagine a tape recorder started a clicking sound in a precise pattern and the canyon walls are reflecting the echoes. And now imagine yourself in a part of the canyon far away enough from the emitter where the strength of the emissions (sound volume) is equal to the echoes coming off a canyon wall near you.
You would have a very hard, if not impossible, time figuring out which of the constant stream of sound coming from different directions are the emissions and which are the echoes.
It’s not an easy solution for a SARH, especially if you switch its parent radar to something else. But a much easier solution for the ARH which has its own receiver and emitter even when transferred to another system.
No. ARH and SARH missiles do not use doppler. They use continious wave illumination, same techniques used by old aircraft before doppler was used.
Basically the analogy is more like a flashlight in a dark room. If I shine a spot with a flashlight, the lighted spot is the same whether or not you hold the flashlight or someone else’s. It should still give you the bearing.
SARH and ARH missiles, in the homing stage, only rely on bearing (direction).
You sure on the IR Alamo? I thought R-27ET is just the R-27ER with a IR seeker for the terminal phase. The datalink should be there for both.
According to Overscan, the datalink is non functional, and the missile is lock before launch. The R-27ER is used as a rear aspect missile.
True. Radar degrades from ground clutter and which is why we have lookdown/shootdown sets for mainly strikers and some interceptors like the F-14 (to deal with sea skimming cruise missiles.)
But radar deteriorates much less in comparsion to IR over long distances in air for most fighter combat and interception. There is simply no comparison between IR and radar aquisition and tracking ability, no matter how quickly IR has developed (actually radar development is coming along just as quickly if not faster.)
Not true. Only long wave radar does not deteriorate so badly. Short wave radar does, and missiles use short wave X or K band.
Discerning faint energy at distance from sun, reflections of glare on water or ice or cloud that come between the seeker and target is much harder than a radar wave actively striking a target and gaining a signal.
Most IR missiles today have long figured out what are targets and what are not targets (like homing in on the sun). some missiles ability to discern is so discriminating they can see through flares.
Infrared (heat) released from the engines is at the order of magnitudes greater in radiant energy than reflected radar. The difference is much greater than a firecracker against a stick of dynamite.
The ARH will have a longer acquisition range than an IR one for the same diameter. Even if the target lit up its afterburner and has its arse facing your missiles.
Wrong here. ARH missiles like SARH are not superior to IR ones in rear aspect attack. The difference in radiant energy between reflected radar vs. heat is like a bonfire vs. Mt. Krakatoa. Guess which one makes a far more reliable and stronger signal source.
In fact, both ARH and SARH missiles have their ranges cut drastically in the pursuit rear aspect mode. Probably only a third compared to the head on range. That’s the reason why the Russians developed long range IR BVRAAMs, to solve that defiency against rear aspect attacks.
The seeker acquisition range of the new ASRAAM is supposed to be 15km (or 9 miles. ) There shouldn’t be anything close today even though a AIM-9 or Python has a listed range of 9 or 10 miles. That’s flight range, not seekerhead acquisition.
That’s only frontal, not rear aspect. I heard someone tell me the seeker head of a Python 3 or 4 can acquire a target a hundred km away if the target is that hot.
You know, you’re right on the J-7E. I probably have seen the PL-8/PL-5 repeatedly on the J-7E and not the J-8II.
But it’s the same argument. The PL-8 has greater range and it needs to be cued from a radar. It is large and heavy because it is intended for a greater flight range than other IR AAM. It has a 15km range. But its seeker’s acquisition is nowhere near 15km.
The flight range of the Python 3 or PL-8 is said to be around 22km. Maybe 25km. Depending on your frontal aspect and how hot the target is, it’s only between 5 to 10km for the seeker, in the front. But there is no fixed rule here. It can acquire the target at 15km or even 20km if the target is hot enough. It can also depend on how long the seeker may be ‘staring’ at the target, or the contrast of the target against the background. If I’m locking against the target in an upward attack and the target is set against a clear blue sky, I may get a better lock. There are so many factors at work here.
crobatoSome interesting new sub that isn’t a 039 Song class.
crobatoIt appears not to have interested buyers or parties, so development appears on hold until you have some interest.
crobatoINS can have two forms, with and without datalink. The two are not mutually inclusive. The Derby can have INS but without datalink. In this case, without datalink updates, the chances of “missing” the target with the seeker acquisition basket is greater, but on the other hand, you have a true fire and forget missile. The AMRAAM can operate on both modes actually.
Without datalink, your lockon ranges aer much shorter but on the other hand, the Israelis are not big believers in BVR and still hold the concept of WVR and mixing it up, king. This explains their priority in the development of WVR missiles as opposed to BVRAAMs with other countries. The Derby is what you may call a Just Beyond Visual Range missile, whose design is to emphasize maneuverability rather than range. Note how far the canards are to the front, which emphasizes agility again. In that sense, the Derby belongs to the small group of “JBVRs” that include the Mica and the R-Darter.
crobatoAgain that depends on when you fire the missile. The AMRAAM is entirely autonomous within range of its radar seekerhead just like an IR AAM is within the range of its infrared seeker.
Except that to do that, your range must be pretty close. Take the 16km figure for the R-77 as a reference. You don’t have a big receiver, and you don’t have a big emitter.
Now is an extended ranged IR missile like the IR versions of the Ash and R-27 fire-and-forget?
Yes.
Again, that is why it is much harder to integrate a SARH missile with a new radar that the SARH was not originally paired with. The ARH uses its own illumination.
It is not hard to change the illumination frequency used by the radar any more like adding a channel to the TV.
One (SARH) needs to pick echos off a target from a different illuminating device that could be above, below, to the side and, most of the time, behind the missile’s receiver. The other (ARH) has its own illuminator that is always at an exact position relative to the receiver. The problems posed by the two systems are very different.
No. Echoes are still echoes. Regardless what is the direction of the source of the emitter, the reciever stil recieves the signals that are still *directed* at it by the angle of reflection. LGBs work similarly even if the target designator is on the ground.
SARH illumination-beam rider principle is still the easiest and the simplest of all available BVR methods.
I think we arguing about semantics here. Both IR and ARH are autonomous seeker type and are fire-and-forget missiles when fired within their respective seekers’ acquisition ranges.
Yes, but ARH is not autonomous when fired beyond those ranges, which is the primary mission role for those missiles.
If you insist that an AMRAAM or R-77 is not fire-and-forget at their extreme ranges, then okay, that is a point that could be made. But an IR AAM with extended range like a IR Ash or Alamo is not either under that same definition. Nor is a long range, heavy IR AAM like the Python series which need radar cuing.
IR Ash and Alamo are true fire and forget, and they are meant for extreme ranges, so long you’re facing the target. The IR Alamo does not work with a datalink.
Range between SARH/BVR and IR had always stayed constant at around the factor of four or five. When the Sparrow B in Vietnam had a range of 18 miles, the AIM-9 was at 2.6 miles.
Yes, but not the seeker range.
IR degrades quickly over distance because of things like sunlight, reflections from bodies of water, clouds, etc. compared to radar. The IR seeker head itself needs to be cooled than the surroundings.
Radar degrades quickly on the other hand, the closer your are to the ground or if your radar is pointing to the ground.
If it is 1x then why bother going through the expense of building ARH AAMs?
I don’t think we have a true figure for the AMRAAM seekerhead’s acquisition range. I’ve heard anything from 10 to 15 miles (25km.)
The key word is the lelement of surprise. if you lit up your target with STT from afar, the RWR goes off, and the target knows it is being attacked. Then it can take evasive procedures.
With ARH, the target is only alerted when the missile’s emitter goes live. TWS won’t alert the target that he is being specifically targeted. However, you can say that the same advantage holds for SARH+datalink INS, since the target is only warned when the parent fighter goes STT on the terminal phase flight of the missile.
The key advantage of using ARH is multiple target tracking and engagement. This is the natural situation where you cannot mind all things at the same time, creating a state of “forget”. Multiple targeting with SARH + datalink INS is possible but requires the radar to juggle STT modes so fast among different missiles in flight. ARH elliminates the juggling act.
Ships can engage multiple targets with SARH because ships carry seperate illuminators. Fighters don’t have that luxury.
The acquisition range of the average IR is not 15km. The PL-8 has a range of 15km but it can’t acquire a target without a radar at 15km.
You are only talking about a frontal aspect. In the rear aspect, when you’re facing the target’s afterburners, the range can be huge—enough to justify the relatively enormous range of the R-27ER.
A setup we see often is J8II with two PL-8s and two PL-5s. That is basically using the PL-8 in the same role as a shorter-legged AMRAAM. The terminal stage when the IR seeker could acquire is probably 5-8km for the PL-8. But its engagement range is greater than the PL-5.
Perhaps, but I don’t really see the J-8II carry PL-5s even if they can. They tend to carry all four PL-8s, maybe even six if you don’t have tanks. It is the J-7E and J-7H that you are talking about with the configuration you described. The reason why the PL-5 exists is that the PL-8 is a heavy and draggy missile, which limits its use on small fighters and for use on wing tip rails. That’s why fighters with wing tip rails use PL-5s like the JH-7 and the FC-1. In the JH-7A, the pylon next to the wing tip rail is actually for the PL-8.
Why the J-10 does not use wingtip rails with PL-5s boggles the mind. They would have easily added two hardpoints on the plane with this.
Some refresher on SARH missiles.
There are two kinds of SARH missiles. The first and earlier one does not have a datalink. The missile is launched from the rail with the seeker already live, and the target being illuminated already by the parent fighter. All the earlier Sparrows like the AIM-7F belongs to this group. From the moment, the radar mode should be on STT, which also have the illumination.
The second type uses an INS system with datalink. The AIM-7M/P belongs to this. The target can be selected and targeted while at track while scan. With this system, the target is not alerted by the STT when the missile is launched. When the missile reaches terminal phase, a judgement made by the radar, the seeker is activated and the radar switches to STT automatically and lights the target. This gives you a better element of surprise, since by the time the alarm goes on, the missile is already close to the target (less than 20km or so). With INS the missile does not have to take a homing path, but an interception type course. This increases range and the possibility of a kill since the missile will be a step ahead of the target, the best situation with a proximity blast.
PL-11A belongs to the first group.
PL-11B belongs to the second group.
PL-11C is another beast, the same airframe fitted with the AMR-1 ARH seeker, so it’s not really part of the discussion on SARH.
The FD-60 China is proposing to Pakistan may belong to the second group.
The SARH AA-10 Alamo which has a datalink, appears to be on the second group, but functionally according to some people, the datalinked INS does not work that well, so it works more like the first group. However, one cannot rule out that later blocks of production AA-10R to have improved datalink INS which can make it work more like the second type.
crobatoHere it is … my second try !!! 😀
Hehehe, it looks much more like a real plane now, rather than a concept sketch. Got a neat MiG-23 feel to it, but that should be the case historically, since during the seventies, when China acquired a few Egyptian MiG-23s (now display pieces on the deck of the Minsk park) the Chinese were seemed so intent adding MiG-23 like features on their planes, so enamored of the Flogger they were.
The ventral fin would be foldable of course.
I wanted the larger, rounder radome since it is much better to fit a larger and more capable radar, something that the Chinese would inevitably conclude is better than the needle like nose. You have the JH-7 development to show this trend.
crobatoI am well aware of what Pearl Harbour was; but it was pre-emptive offense. Japan was the aggressor. But some where along the line of this discussion sneak attack has been mentioned, and then historical precedents were mentioned, and fair enough. But you have to look at the Japan of then and the Japan of now, and the world as a whole as well.
The US knew what was coming and they ignored it then. They were just looking to get involved with the war in Europe. When the US embargoed Japan for certain raw materials, the stage was set and inevitable.
Imperialism is dead. This whole thing of sneak attack is rather more general anyway, anyone who may feel severly threatened by a neighbour might simply step up and strike first. Lets get back to the topic.
Tell that to General George Dubya “Custer” Bush. Sounds like his preemptive doctrine.
crobatoBut, i wouldn’t be surprised that there are quite some Japanese pilots with AMRAAM experience via simulators. AS to computer standards, Crobato, i thought you know more than that about computers, these are the Japanese afterall. There’s a reason when you don’t want something to be compatible, and then there’s reasons why you can make something that’s not only compatible but better.
And how does that make it more compatible with AMRAAM and US avionics systems?
NEC designed a PC bus standard of their own, and claimed it better than IBM’s. Funny that the rest of the world followed IBM’s, including other Japanese companies.
I can only tell you that you know nothing about computers. If you create a nonstandard interface for yourself to lock your market in, you also lock yourself out. The US creating standards for itself and for the rest of the world to follow are being done for a reason.
A very good example of this is Japan’s celphone business. Whatever is NTT/DoMoCo is running is incompatible with the rest of the world, making their celphones virtually useless outside of the country. While the rest of the world follow competiting standards; South Korea CDMA, the US between CDMA (services by Verizon, US Sprint) and GSM (services by AT&T Mobile, Cingular), China-S.E. Asia-Europe all GSM (sets by Nokia, Ericcson, etc,.)
As to Chinese military, surprise attacks, blah blah blah, the point is how these “things” work in China as in comparison to the US or Japan. The Iraq war at least took a few months, if Chinese leaders want you got your war tomorrow. Nevermind the strategic situations, that’s the nature of the power structure of the CCP. No one can deny that.
As to the economy, the point is Yahoo25 mentioned “irrelavant”…even the 20th economy of the world isn’t irrelevant. Mind you Japan is a very very rich country even with a decade of recession.
Mind you Japan has a bank debt in the trillions, and at least a significant portion of which are bad, much like the US. Japan, thanks to its surplus, did not go to a depression, but a decades old recession instead—the only sign of increased economic activity are due to exports to China, and product deflation has been caused by, guess what, imports from China.
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