Sights and Sighting Mechanisms

instruments and devices for aiming firearms or missiles at a target. Sights and sighting mechanisms are used to impart the required spatial orientation for firearms according to angles on the horizontal and vertical planes.

There are open barrel, optical, electron-optical, radar, automatic, and nonautomatic sights. Open barrel sights are used on carbines, submachine guns, machine guns, and grenade launchers. The most common are optical sights, which are used in artillery (including antiaircraft, coastal, and ship artillery) and on tank and aircraft cannon and machine guns. They make it possible to see an enlarged correct image of the target, or aiming point; provide corrections for velocity and direction of movement of the target and weapon (for example, a weapon in a tank, on an aircraft, or on a ship); and determine settings with corrections for ballistic, atmospheric, and other conditions when firing at airborne targets. Horizontal laying of the weapon is achieved by deflection and by a traversing mechanism. Vertical laying is accomplished by the sight itself and by an elevating mechanism.

Most modern ground artillery guns have sights for direct and indirect laying for fire against observed and unobserved targets. Tanks use range-finder sights, periscopic and optical sights, and computers with actuators to set the sight angles. The sights of tank guns have stabilized sighting lines on two planes to eliminate any effect on precision of fire from vibrations in the tank or gun while in motion.

Electron-optical sights consist of an electron telescope, infrared spotlights, and power pack. They give a visible image of targets at night and are used for aimed night fire by small arms, antitank guns, and tank guns. They are classified by type of action as active, where the infrared spotlight illuminates the target; passive, without illumination; and passive-active. The operating range of illumination sights is up to 1,500 m.

Radar sights are used for firing aircraft cannon and antiaircraft, ship, and ground artillery and for bombing when the target is not visible to the eye, such as at night or in rain or fog. These sights include a radar device to detect moving targets and determine their distance and azimuth, as well as a computer and a control panel. Small radar devices are also used on small arms, for example in the US armed forces.

Aviation sights are classified as bomb and torpedo sights and sights for firing artillery and missiles from the air. These sights have optical and radar devices to observe the target and measure its coordinates and parameters of movement when flying during the day, at night, in fog, and in clouds. They also have computing units to determine the position of the aircraft or gun in space and make it easier to hit the target with a shell, bomb, or torpedo.

The sights used at missile complexes provide spatial orientation for the missile and measurements for the control system before launching.