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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

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