Gun stabilizer

A gun stabilizer is a device intended to facilitate aiming a gun by compensating for the motion of the platform on which the gun is mounted. The primary armament of all US tanks was stabilized at least by 1944.[1] Some attempt was made to stabilize Soviet tank guns as early as 1938.[2] The defensive guns of the B-29 bomber were also electronically aimed, though platform rotation was not the main problem for them. This was an important factor in World War II, because it allowed much greater accuracy while on the move and, in addition to allowing a faster average speed, the survivability of a vehicle in battle depends on its unpredictable motion that disrupts the enemy gunner's prediction of where the target is going to move next.

The mechanism usually includes an angular reference device such as a mechanical or optical gyro and servo mechanisms. In the case of a tank, there is one servo stabilizing the turret and another for the elevation of the gun. The aiming is then done by control input to the mechanism, rather than directly on the gun. The control mechanism usually has other functions, such as applying super-elevation and leading the target according to its velocity, making it a fire-control system, and some guns are entirely automatic.

There are many forms of gun stabilization, such include the single-plane stabilizer, a simple stabilizer system that only stabilizes on a vertical axis, the shoulder-stop stabilizer, that follows a principle due to the elevation mechanism on smaller caliber guns, and the two-plane stabilizer, that stabilizes both the vertical and horizontal axles.