AGM-45 Shrike

AGM-45 Shrike is an American anti-radiation missile designed to home in on hostile antiaircraft radars. The Shrike was developed by the Naval Weapons Center at China Lake in 1963 by mating a seeker head to the rocket body of an AIM-7 Sparrow. It was phased out by U.S. in 1992 and at an unknown time by the Israeli Air Force (the only other major user), and has been superseded by the AGM-88 HARM missile. The Israel Defense Forces developed a version of the Shrike that could be ground-launched and mounted it on an M4 Sherman chassis as the Kilshon (Hebrew for "Trident").

History

The Shrike was first employed during the Vietnam War by the Navy in 1965 using A-4 aircraft. The Air Force adopted the weapon the following year using F-105F and G Thunderchief Wild Weasel SEAD aircraft, and later the F-4 Phantom II in the same role. The range was nominally shorter than the SA-2 Guideline missiles the system was used against although it was a great improvement over the early method of attacking SAM sites with rockets and bombs from F-100F Super Sabres. A Shrike was typically lofted about 30 degrees above the horizon at a Fan Song radar some 15 miles (25 km) away for a flight time of 50 seconds. Tactics incrementally changed over the campaigns of 1966 and 1967 until the advent of the AGM-78 Standard ARM. This new weapon allowed launches from significantly longer range with a much easier attack profile, as the ARM could be launched up to 180 degrees off target and still expect a hit and its speed allowed it to travel faster than the SA-2. Even after the AGM-78 entered service, the Weasels still carried the Shrike because the ARM cost about $200,000, while a Shrike cost only $7,000. If USAF pilots expended an ARM they would have to fill out a lengthy form during debriefing. A somewhat standard load for the F-105G was a 650 US gal (2,500 L) centerline fuel tank, two AGM-78s on inboard pylons and two Shrikes on the outboards. The mix varied slightly for jamming pods and the occasional AIM-9 Sidewinder but this was the baseline.

Although the Shrike missile did not enter regular service with the United Kingdom, it was supplied to the RAF for use in the Falklands War of 1982. RAF Shrikes were fitted to modified Vulcan bombers in order to attack Argentinian radar installations during Operation Black Buck. The main target was a Westinghouse AN/TPS-43 long range 3D radar that the Argentine Air Force deployed during April to guard the Falklands' surrounded airspace. The Argentine operators were aware of the US-supplied anti-radar missiles and would simply turn it off during the Vulcan's approaches. This radar would remain intact during the whole conflict. However, air defences remain operational during the attacks and the Shrikes hit two of the less valuable and rapidly replaced secondary fire control radars. As a result of this experience next generation missiles were designed to "remember" the radar position even if they were turned off. Also, following a Vulcan making an emergency landing at Rio de Janeiro, Brazilian authorities confiscated one Shrike which was never returned.

Variants

The Shrike's limitations are characterized primarily in the fact that subvariants abound, each tuned to a different radar band. Angle gating, used to prioritize targets, was included in every subvariant of the AGM-45A and B after the A-2 and B-2. It was also slow and the lack of punch in the warhead made it difficult for bomb damage assessment, as well as inflicting any damage to the Fan Song Radar vans beyond a shattered radar dish, an easy item to replace or repair. The short range, combined with its lack of speed (compared to the SA-2 SAM) made for a difficult attack. The missile had to be well within the range of the SAM and if a SAM was fired the SAM would get to the aircraft first. Also the missile had few tolerances and had to be launched no more than + or - 3 degrees from the target. Many pilots in Vietnam did not like the Shrike because of its limitations and its success rate of around 25%.

The differences between the AGM-45A and B are in the rocket motor used, and in the warheads capable of being fitted. The AGM-45A used the Rocketdyne Mk 39 Mod 0 (or apparently in some cases the Aerojet Mk 53 Mod 1) motor, while the AGM-45B used Aerojet Mk 78 Mod 0 which greatly increased the range of the missile. As for warheads, the Mk 5 Mod 0, Mk 86 Mod 0, and WAU-8/B could all be fitted to the AGM-45A and were all blast-fragmentation in nature. The AGM-45B made use of the improved Mk 5 Mod 1 and Mk 86 Mod 1 warheads, as well as, the WAU-9/B, again all blast-fragmentation in type.

The following table provides information on what radar bands were associated with certain guidance sections, and the subvariant designation.

For unknown reasons, -5 and -8 were not produced.

External links

* [http://www.designation-systems.net/dusrm/m-45.html The AGM-45 Shrike at Designation Systems.net]
*International Signal and Control