great topic
got this from aus air power
http://www.ausairpower.net/APA-Rus-BVR-AAM.html
Russian BVR Combat Philosophy
The Russian paradigm of BVR combat has its origins in the Cold War period, when Soviet operational analysis indicated that the low kill probability of missile seekers and airframes, especially if degraded by countermeasures, would be a major impediment to success. By the 1970s the standard Soviet technique in a BVR missile launch was to salvo two rounds, a semi-active radar homing weapon and a heatseeking weapon. To this effect some Soviet fighters even included a weapons select mode which automatically sequenced the launch of two rounds for optimal separation.
The mathematics of multiple round missile engagements are unambiguous - the size of a missile salvo launched is a stronger driver of success than the actual kill probability of the individual missiles. If the missiles are wholly identical by type, then the following curves may be optimistic, insofar as a factor degrading the kill probability of one missile is apt to have a similar effect on its siblings in a salvo. However, where the missiles differ by seeker type and guidance control laws, then the assumption of statistically independent missile shots is very much stronger.
A question often asked is why are Sukhoi Flanker variants equipped to carry between eight and twelve BVR missiles? The answer is a simple one - so they can fire more than one three or four round BVR missile salvo during the opening phases of an engagement. In this fashion the aircraft being targeted has a difficult problem as it must jam, decoy and/or outmanoeuvre three or four tightly spaced inbound missiles. Even if we assume a mediocre per round kill probability of 30 percent, a four round salvo still exceeds a total kill probability of 75 percent.
A critical question which must be asked when assessing the effectiveness of Russian BVR tactics is that of Western tactics and the effectiveness of the AIM-120 AMRAAM, the principal Western BVR fighter weapon. The AIM-120A AMRAAM was introduced at the end of the Cold War to provide a "fire and forget" active radar guided weapon with a midcourse inertial guidance system and datalink support provided by the radar on the launch aircraft, allowing multiple concurrent shots. The AIM-120A was followed by the incrementally improved B-model, and then by the "short span" AIM-120C-3 sized to fit the F-22A weapon bay. The AIM-120C-4 has better kinematic performance introducing a larger rocket motor and shorter control section, and a better warhead, while the AIM-120C-6 introduced a better fuse. The latest AIM-120D introduces a redesigned seeker built for better durability in high vibration carriage environments, a two way datalink, GPS to supplement inertial guidance, incrementally improved kinematics, and better seeker performance against high off-boresight targets.
Illustrative examples are the F/A-18E/F Super Hornet and F-35 JSF, the latter armed in an air superiority configuration with two, the former with up to six AIM-120s [3]. Assuming the Flanker driver does not exploit his superior missile kinematic range and shoot first - an optimistic assumption - then the best case kill probability for the AIM-120 shooter firing two to four rounds is better than 90 percent. However, if we assume that hostile jamming and manoeuvre degrade the kill probability to around 50 percent - a reasonably optimistic statistical baseline here - then the total kill probability for a two round salvo is optimistically around 75 percent, and for a four round salvo over 90 percent. Arguably good odds for the four round salvo, only if the missile kill probability sits at 50 percent, but the F/A-18E/F or F-35 JSF will have expended all or most of its warload of AIM-120s and be unable to continue in BVR combat. In a "many versus many" engagement, the low speed of both types leaves them unable to disengage and will see both types subsequently killed by another Flanker.
This best case "many versus many" engagement scenario sees the F/A-18E/F or F-35 JSF being traded one for one with Su-30MK/Su-35BM Flankers in BVR combat, which is the general assumption made for WVR combat between like opponents, and representative of many historical attrition air campaign statistics. To achieve this best case "many versus many" outcome of trading F/A-18E/F or F-35 JSF one for one, we have stacked a series of assumptions against the Flanker - dumb Flanker pilots not exploiting a missile kinematic range advantage, dumb Flanker pilots not exploiting a firepower advantage, Russian BVR missile seekers no better than the AIM-120, and Russian DRFM monopulse jammers achieving a less than 50 percent degradation of AIM-120 kill probability [4].
A competent Flanker driver gets the first shot with three or four round salvo of long burn R-27 variants, with mixed seekers, leaving one or two remaining salvoes of BVR missiles on his rails, and the same Flanker driver will have modern DRFM monopulse jammers capable of causing likely much more than a 50 percent degradation of AIM-120 kill probability. With a thrust vectoring engine capability (TVC), the Flanker driver has the option of making himself into a very difficult endgame target for the AIM-120 regardless of the capability of his jamming equipment. Since all of the AIM-120s fired are identical in kinematic performance and seeker jam resistance, any measure applied by the Flanker driver which is effective against one AIM-120 round in the salvo is apt to produce the same effect against all AIM-120 rounds - a problem the Flanker driver does not have due to diversity in seeker types and missile kinematics.
Currently classified capabilities such as the use of the APG-79 or APG-81 AESA radar as an X-band high power jammer against the Russian BARS or Irbis E radar are not a panacea, and may actually hasten the demise of the F/A-18E/F or F-35 JSF in a BVR shootout. This is for the simple reason that to jam the Russian radar, the APG-79 or APG-81 AESA radar must jam the frequencies being used by the Russian radar, and this then turns the APG-79 or APG-81 AESA radar into a wholly electronically predictable X-band high power beacon for an anti-radiation seeker equipped Russian BVR missile such as the R-27EP or R-77P. The act of jamming the Russian radar effectively surrenders the frequency hopping agility in the emissions of the APG-79 or APG-81 AESA radar, denying it the only defence it has against the anti-radiation missile. A smart Russian radar software designer will include a "seduction mode" to this effect, with narrowband emissions to make it very easy even for an early model 9B-1032 anti-radiation seeker.
The flipside of the electronic combat game is no better. The F-14A/B/D included the AAS-42 Infrared Search and Track set which allowed a target to be tracked despite hostile jamming of the AWG-9/APG-71 radar. It is clear that the addition of the podded AAS-42 to the Super Hornet and "air to air" use of the JSF EOTS are intended for much the same purpose. While this may permit the continuing use of the AESA radar to datalink midcourse guidance commands to the AIM-120s, it does nothing to deny the Flanker its own BVR shot. The notion that the defensive jamming equipment and infrared decoys will be highly effective against late model Russian digital missile seekers can only be regarded to be optimistic.
In electronic warfare terms neither side has a decisive advantage, but the Flanker does have a decisive advantage in aircraft and missile kinematics and in having up to six times the payload of BVR missiles to expend. The simple conclusion to be drawn is that operators of the F/A-18E/F or F-35 JSF should make every effort to avoid Beyond Visual Range combat with late model Flankers, as the best case outcome is parity in exchange rates, and the worst case outcome a decisive exchange ratio advantage to the Flanker. Given the evident design choices the Russians have made, this is not an accident, but rather a consequence of well thought through operational analysis of capabilities and limitations of contemporary BVR weapon systems.
can fire before others even detecting it? And one more thing BVR missiles are never launched at max range because max ranges are for non-maneuvering target, at a high altitude, and head-on aspect.
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