Zvezda Kh-25 (AS-10 Karen)
The Kh-23 missile was very difficult to operate. After having been fired, it required continuous control by the pilot so that the pilot had to view the target image and the missile image as well as the sight screen. The necessity of continuously watching three images diverted the pilot from other tasks was very dangerous during combat. The distance to the target was, moreover, logged by the pilot manually on the basis of rough "eyesight" estimates and thus with significant errors.
Other methods of guidance were sought, therefore, and the use of a laser for target indication to a guided missile became the choice. Work on this project was carried out by the "Zvezda" OKB jointly with Sukhoy's engineering group, the system developed by them being designated as the Su-17MKG (initial plans also included missiles with laser guidance as weapons for Su-7BM aircraft, but the autopilot of these aircraft was weaker and not able to ensure adequate damping of vibrations and thus sufficiently accurate aiming).
While the Kh-23 was still being tested, its Kh-25 version (Article 71) was being prepared with a 24N1 semiactive laser homing head, using light rays reflected by the target upon their incidence from the first Soviet aircraft laser station ''Prozhektor-1'' (or possibly from a laser station on the ground). The missile was also equipped with an SUR-71 autopilot.
Inasmuch as the Kh-25 version did not need a Delta system, instead an additional warhead weighing 24 kg to supplement the 113 kg warhead in the front, was placed in its tail section. The "Prozhektor" laser station had been built by the "Geofizika" [Geophysics] SKB (D. Khorol chief engineer). Flight tests of the Kh-25 missile on an Su-17M aircraft, also carrying a "Prozhektor" laser, began toward the end of 1973, after which followed in autumn 1974 Government Qualification tests of the Su-17KMG complex. Both Kh-23 and Kh-25 missiles were also tested on Ka-25 and Ka-27 helicopters.
The experience acquired during work on radio command-guided Kh-23, laser- guided Kh-25, and Kh-25 antiradar missiles was all applied to a new design: of the "Modulnaya" [Modular] Kh-25M missile (Article 71). This one became ultimately the most popular Soviet missile of its class and replaced earlier types. In 1975-76 it was approved for ordnance, especially as weapon of the MiG-27, then later also as weapon of almost all other aircraft and also of some helicopters such as Ka-50.
The Kh-25M missile is series produced in three versions, all using the same engine, autopilot, warhead, power supply, body with wings, and other components. Only the guidance heads are different. The Kh-25MP antiradar missile (Article 711, NATO's AS-12 Kegler) is similar to the Kh-27PS with an almost identical outer appearance. The Kh-25ML (Article 713, NATO's AS-10 Karen) has a 24N1 laser guidance head and thus the same one which the Kh-25 has. The Kh-25MR (Article 714, NATO's AS-10 Karen) has the guidance head in the nose section replaced by a deflector and a Delta radio command-guidance system in the tail section, just as in the earlier Kh-23M missile. The latest version of the Kh-25 missile is the Kh-25MTP with a thermal-imaging guidance head.
|Join the GlobalSecurity.org mailing list|