SwingKid

http://forum.lockon.ru/showpost.php?p=119905&postcount=11 -SK

http://forum.lockon.ru/showpost.php?p=134143&postcount=124 -SK

As you read which - the FAS description or the Russian text? -SK

You misspelled "my". -SK

Here's something you might like: http://ship.bsu.by/main.asp?id=1000005 It seems from this text that both are correct - if my Russian has not completely disappeared, the missile has an expanding rod warhead packed inside a fragmentation layer. Great video of the missiles in action!! (the third one at bottom). I'm not sure it resolves any of our debates though - the missile containers are shown in the reload position for a moment, but this doesn't resemble any of the previous images that lacked missile containers. The missile also seems to follow an erratic path, but eventually appears that it DOES hit the target despite this. The target seems to resemble more of a drone helicopter carrying a big flare (to aid optical tracking?) than an incoming missile, but that's just my opinion. You can also see the cameraman can't keep the video camera still on the target, so I don't know how manually-controlled optical tracking with 8x magnification should be kept steady against an incoming missile. Fun to watch, anyhow. -SK

(shaking head) Oh dear... Now that I read the Russian text again, it seems that Tunguska DOES need optical tracking for use of missiles, FAS was correct the first time! This is a job for EvilBivol - we need someone who can really read this Russian text and make sense out of it. :( -SK

Are you trying to say that a TOW can hit a Maverick? :) -SK

Assumes an "inertialess" SAM that responds instantaneously and without control error to any deviation of target LOS. Target LOS deviation would depend on the PN homing accuracy of the Maverick itself, i.e. how much it "sidewinds" - should be low anyway because it's locked on a stationary target. Reaction time issue and ECCM are for a separate analysis. -SK

One book says 4, the schematic on the diagram seems to show 6, the web site says 8. Ok, I don't know - multiply accordingly. I thought "5 meters guaranteed detection against helicopter" suggested 1/10th guaranteed detection against something 1/10th helicopter size. The analysis was for command-to-line-of-sight (CLOS) guidance. Rotation of the missile might contribute to increased fuze probability, but it would also contribute to increased flight control errors of the missile, so I ignored rotation as if it was roughly self-cancelling. AFAIK unguided rockets and beam-riders are spun at high rate but it's not good for other guided missiles, and this is why AIM-9 was given rolleron stabilizers - to reduce rotation and improve controllability and precision. Taking rotation into account would also chip away at the "if it can shoot down an ASM it can shoot down a Maverick" argument, because then we need to account for closure rate and the target's total length. Note that in the analysis, I assumed all missiles flew a perfect trajectory with no "sidewinding" - only radar tracking error was given so only radar tracking error was taken into account. Then again, Wags often knows things I don't... ;) -SK

As far as Tunguska goes, I already posted all the details that I have, directly quoted from the Russian text: - four lasers, - cannot assure detection of a helicopter beyond 5 m, - was replaced by a radio fuze to improve performance against ALCM It doesn't sound as if this Russian-made 1980 laser fuze was using any such scanning technology. -SK

Apologies first. (1) It appears that the information posted from the FAS site, referenced in message #58, may be mistaken. From the Russian text, it appears that the optical-tracking method described for Tunguska may actually be just a backup manual over-ride in case of ECM disrupting the normal automatic radar tracking during a radar missile engagement. This would be consistent with the design of other Soviet-era AD systems such as Shilka. (2) I think I've figured out now how to interpret the quoted radar tracking numbers in the Russian text, to produce an estimate of AD effectiveness against Maverick. Let's consider original Tunguska with laser fuze first, then Tunguska-M missile with radio fuze, then Pantsyr, then Tor. Tunguska 9M311 with laser fuze (IOC 1982) 9M311 fuze has four laser beams arranged around the missile. Against a typical helicopter target, it has a quoted "certain" detection range of "5 m", "possible" detection range of "15 m". If we treat the AGM-65 Maverick as having a body diameter of about 60 cm, this body will fill a 45-degree field of view at a distance of about (30 / arctan(45/2)) = ~34 cm. That is, the 9M311 missile must pass within 34 cm of a Maverick or similar-diameter target in order to achieve a 50% probability of detection and detonation. The tracking radar has a quoted mean-square angular tracking error of "2 minutes", and the missile has a minimum range of 1.5 km, since it needs to jettison its rocket booster before it can begin receiving command guidance. At the 9M311's minimum engagement range, the tracking radar is measuring the position of the incoming target with an average lateral error of about (1500*tan(2/60)) = ~87 cm. Without describing the math, we can estimate the probability of the missile approaching within 34 cm of the Maverick by using the "erf" function: http://www.mhtl.uwaterloo.ca/old/courses/me303/calc/func_calc.html Enter (34/87/sqrt(2)) = ~"0.276" for x and click "Calculate" to get a probability of about 30%. So, at the minimum missile engagement range, 9M311 has a 30% chance of being guided close enough to the target and a 50% chance of detonating. Thus, Pk of 9M311 against Mavericks, Harpoons, and other small targets should not exceed: 15% at 1.5 km minimum range 8% at 3 km range 4% at 6 km range 3% at 8 km maximum range Tunguska-M 9M311M with radio fuze (~1995) In the 9M311M, the laser fuze was replaced with a radio fuze for "improved effectiveness against cruise missiles". We'll assume the radio fuze is not a limiting factor, but it still uses the same expanding-rod warhead which, according to the Russian text, loses its effectiveness beyond 5 m radius. So, 9M311M needs to pass only within 5 m of the target to score a kill. Tunguska-M may also have a newer tracking radar with improved resolution, but since we don't have any data about it, let's assume that we use this missile with existing Tunguska radar parameters. Now that 5 m is larger than 87 cm, we calculate different "x" values according to range At 1.5 km, the "2 minutes" lateral error equals 87 cm, (500/87/sqrt(2)) = 4.06 at 3 km, the "2 minutes" error equals 175 cm, (500/175/sqrt(2)) = 2.02 @ 6 km, 349 cm, (500/349/sqrt(2)) = 1.01 @ 10 km, 582 cm, (500/582/sqrt(2)) = 0.607 Enter these values into the calculator linked above to estimate Pk of 9M311M against Mavericks, Harpoons: 100% at minimum 1.5 km range 100% at 3 km range 85% at 6 km range 61% at 10 km maximum range Now, these are only estimates - Pk of 9M311M against Maverick is probably not really 100% sue to other sources of error we didn't consider. But, those sources of error will also affect 9M311, and we can already see that the probability of a normal Tunguska that is in service with Russian forces hitting a Maverick should be negligible compared to Tunguska-M, and this is primarily because of its laser fuze, that was designed for a different task. Pantsyr 9M335 and 57E6 with radio fuze (current development) I won't spend time on these systems because I don't have good enough data, except to point out that the primary means of expanding engagement envelope was to increase the warhead size - from 9 kg to 16 and 20 kg for 9M335 and 57E6 respectively. We can imagine from previous analysis how this will increase the original 5 m kill radius of the 9M311(M) against small targets, and thus affect Pk. Tor 9M330 with radio fuze (IOC 1986) Monopulse tracking radar has quoted mean angular error of only "0.3 minutes". Missile warhead is about 15 kg, let's estimate 6 m lethal radius. 100% at minimum 1.5 km range 100% at 3 km range 100% at 6 km range 100% at maximum 12 km range Tor's main advantage seems to be, advanced monopulse array antenna with ~6x greater accuracy measuring the position of the target in both planes. So, IMHO Tor and Tunguska are not generally comparable. -SK

True, I've been interchanging "SACLOS" and "beam-rider", sorry. At question was the precision with which the radar can know the target's position - i.e. range and angle resolution. The wider the beam, the less precise the tracking. Both beam-riders and command-guided missiles thus have accuracy that gets worse as you go further in range, or as the radar beamwidth gets wider. The quoted resolution of the tracking system seems to hold one of the keys to calculating exactly what the Pk, unfortunately the quoted figures appear to contradict each other. :confused: -SK

And yet... http://forums.frugalsworld.com/vbb/showthread.php?t=95013&highlight=bullet "As a Sergeant First Class Avenger platoon sergeant for the past ten years, I can shed a little light on this subject... There is no way in hell that an Avneger can engage a Maverick in any tactical situation." He seems to think it's not a size issue, but rather the weakness being the human operator being unable to lock the missile onto an incoming missile. i.e. if the Maverick flew laterally like a cruise missile, then it could be done, but NOT head-on. If I understood correctly. :confused: -SK

To add more fuel... It appears that contrary to Tunguska, the Tor system DOES have a widely advertised anti-missile capability. It seems to have been designed for this from the start - still apparently uses SACLOS, but with a narrower beamwidth than Tunguska, and the missile has a larger warhead, resembling Pantsyr. Other modern SAMs like Buk and Tunguska have anti-ARM tactics described in the reference text, but these usually consist of switching frequencies or polarities, having multiple stations work together, blinking or shutting down the radar. But for the case of Tor, the text is very clear: Protection against anti-radiation missiles is achieved by their detection and destruction by own SAMs. Wow. Thanks to D-Scythe for pointing it out. It takes me a while to read through all the Russian text; there are still many systems left to study... -SK

Source? -SK

Agreed... Hmm, I think we miscommunicated somewhere. Throughout this discussion, I've been trying to focus on SAMs, and the insufficient precision of SACLOS guidance. As far as concerns guns, that's a different issue we haven't fully explored. My opinion would be: (a) Shilka has no capability against AGMs because of its ~20 s reaction time, (b) Tunguska and naval Kortik guns have reaction time of ~8 s, so they can engage the weapon only after it has been detected for this amount of time, © Tunguska guns should have 2/3 the Pk of Kortik guns, because of reduced rate of fire. The only part I'm not sure about is how smoothly the Tunguska can switch from optical tracking at missile range, to suddenly dropping the missile guidance and rotating the radar over to track the guns on the target instead. With an 8 s reaction time to lock and fire guns against an incoming target, it would seem to leave no surplus leisure time for guiding the missiles at all... The Tunguska should be trying to lock its guns onto the target long before it actually enters guns range. So, I suspect the system has to choose whether it will use missiles or guns at the beginning of each target engagement, rather than using both as the target passes through one envelope to the other. -SK

I'm not sure how to respond to this, since it seems to suggest that an ATGM is a longer-duration threat than the heliopter that launched it. If the Shilka can't react in time to a pop-up helicopter that needs to stay in view to provide guidance to its ATGM, then it should go without saying that it doesn't have time to react to the ATGM itself. http://www.gruntonline.com/Order%20of%20Battle/PAVN/PAVN_armour3.htm "The firing cycle took about six seconds from initial target acquisition to radar track lockon, but US tests of captured ZSU-23-4 Shilkas supplied by Israel found that the time from acquisition to actual firing took 20-30 seconds for an average crew." Page 14 (speaking about Shilka): "К началу 1970-х гг. вооруженные противотанковыми ракетами вертолеты американского производства наглядно продемонстрировали свои возможности... Анализ показал, что ни одно из зенитиых средств Советской Армии не может успешно противостоять боевым вертолетам." In the early 70s, American-built combat helicopters armed with ATGMs clearly demonstrated their capabilities... The analysis revealed that not a single one of the Soviet Army AAA systems could defend against (such) combat helicopters. Page 15 (speaking about Tunguska): "В дуельной ситуации поединка боевого вертолета с зенитным комплексом... все зависит от того, чья ракета раньше долетит до противника и, поразив его, сорвет наведение вражеской ракеты." In a duel situation between a combat helicopter and the air defense system... everything depends on whose missile hits the enemy first and, destroying it, thereby breaks the guidance of the enemy missile. Page 19 (speaking about Pantsyr): "В отличие от 'Тунгуски', создававшейся в первую очередь как средство борбы с боевыми вертолетами противника, 'Панцирь-С1' разрабатывался исходя из других задач - прикрития от воздействия высокоточного оружия..." In contrast to the "Tunguska", which was created primarily to combat enemy helicopters, the "Pantsyr-S1" was designed to perform different tasks, including defense against precision-guided munitions... The text provides the Pk of Pantsyr against missile-type targets, but I can't find the corresponding value for Tunguska. There is however provided a description of the Tunguska tracking radar precision: "Разрешающая способность станции и ее среднеквадратические ошибки сопровожения цели были, соответственно, не хуже 75 м и 2 м по дальности и 2 град. и 2 д.у. по угловым координатам." Maybe you can help me here: The (tracking radar's) resolution and tracking mean square errors are 75 m and 2 m in range and 2 degrees and 2 [d.u.?] in azimuth/elevation. What's a "d.u." - is it like "mils"? How can they measure range to the nearest 75 m, yet have a measurement error of only 2 m? :confused: -SK

To be fair, there was a time when I thought Shilkas should be shooting back against Mavericks... The game just seemed to easy with 100% effective missiles in Flanker 2. How about ground vehicles that pop smoke to disrupt optical tracking? Except, I don't think AD vehicles carry these... just tanks and IFVs? -SK

Aww shucks, you guys are too nice... How am I supposed to argue? :) Gift for EvilBivol to translate: http://www.ecf.utoronto.ca/~pavacic/scans/tung.zip Note consistent introductory sections regarding how Tunguska launch range requirement evolved from inability of radar-cued guns (ZSU-23-4 Shilka) to protect against helo-launched ATGMs. -SK

Those are intake covers. They're designed to break off in the wind when the missile reaches enough speed to start the ramjet motor. -SK

Are you sure about this? The number "1400" appears in my Russian reference as the size of the Pantsyr's magazine, not rate of fire. Maybe another mistake of English translation? :confused: -SK

It's like the case of a rifle vs. a shotgun, or rate-of-fire vs. . The expanding rod warhead reduces the likelihood of damage by concentrating the firepower into a narrow band, but increases the damage if a hit occurs. This is useful against a large target, but against a smaller one the problem is not how to cripple it, but rather just how to hit it. At what range? Command-guidance accuracy varies according to distance, decreasing linearly the further you go. -SK

Speaking of design objectives, let's compare the Tunguska's 9M311(M) missile, which was designed to keep helicopters out of ATGM range, to the Pantsyr-S1's 9M335 and 57E6 missiles, which were designed to hit incoming missiles. (a) Both Tunguska and Pantsyr missiles are beam-riders. However, the Tunguska radio antenna generates a beam that is 2x2 degrees wide (~200 meters radius at 6 km range). For higher precision (comparable to Su-25T's "Vikhr"), at the terminal phase, the Pantsyr's missile is beam-riding on a laser. (b) Tunguska missiles use a laser proximity fuse. In the Pantsyr, the fuze was changed back to radio, to prevent small targets slipping between the radar beams. © Tunguska missiles carry a 9 kg expanding-rod warhead with 5 m kill radius. The expanding rod warhead is meant to cut hydraulic lines and helicopter rotors. The Pantsyr's 9M335 and 57E6 have fragmentation warhead about doubled to 16 and 20 kg respectively, to ensure proximity kills against targets too small to hit (despite increased-accuracy laser guidance!) (d) Speed of Pantsyr's missiles increased 20-40% with respect to Tunguska's, to improve reaction time. (e) Range of Pantsyr's missiles increased by 50-150% with respect to Tunguska's, to improve reaction time. (f) New multi-channel radars allow simultaneous guidance of missiles to two targets. (g) Even with all these improvements, the Pantsyr's anti-missile capability is only advertised against long-range radar missiles like HARM, which must be fired upon from 8 km range to ensure sufficient reaction time, separation of SAM from booster and guidance to the intercept trajectory. There is still no advertised anti-missile capability vs. Maverick and ATGMs because these are launched from shorter ranges. Instead, Pantsyr operators are specifically instructed to shoot down the aircraft carrying these weapons, before they can fire back. (h) By contrast, Tunguska SAM has advertised 60% hit probability against helicopters, and is rather promoted on the strength of its multi-role capability to hit ground vehicles and (for Kortik, which uses same missile) small ships. The design requirement of the Tunguska, in operation since early 80s, was simply - to counter ATGM-carrying helicopters, that were destroying Shilkas with impunity. Nothing more. The chances of this system to hit a Maverick missiles is practically zero. -SK

And there's more where that came from! No comment. You can PM, or you can draw own conclusions. -SK

The designers apparently considered Tunguska's guns ineffective for this task, so they replaced them with new guns that fire more than twice as many rounds per minute for the Kortik CIWS. The only thing that's the same between Kortik/Kashtan and Tunguska (and thus relevant to the argument whether Kortik's CIWS performance is evidence of what Tunguska can do) is the missile. But as we see, even that is often left out. So, the evidence that Tunguska has any capability to shoot down missiles in real life is, IMHO, none. -SK