9K31 Strela-1 - Development History

Development History

The missiles used in this system were developed alongside the ubiquitous Russian MANPADS 9K32M "Strela-2" (NATO designation SA-7 "Grail") in the 1960s. At first both missiles were intended to be man-portable systems, but as it became obvious that Strela-2 would be far more compact of the two system, the development goals of Strela-1 were changed. Instead of a battalion-level man-portable system the new criteria called for a regimental vehicle-mounted SAM to support the ZSU-23-4.

As a result of the change in role and more relaxed weight limits of a vehicle-mounted SAM, the design team made the 9M31 a much heavier missile, which permitted fewer design compromises than in the case of Strela-2 to achieve acceptable kinematic performance. The most notable difference is the much larger diameter of the missile and a blunt seeker head that occupies the full width of the missile body. With all else being equal, the ability of an optical seeker to detect a target is directly proportional to its diameter, but on the other hand aerodynamic drag increases proportionally to the square of the diameter.

The Strela-1 also had a warhead over twice as heavy, a proximity fuze and more effective control surface configuration to provide better maneuverability at the cost of increased drag. The net result was a missile four times the weight of Strela-2, with only slightly longer reach but otherwise of much better performance.