EYE SHOOTING, PART 1: FIRST PRINCIPLES

There are several different ways in which an aircraft can attack its objective. Most of you've seen or heard something of high-level bombing attacks and probably have some idea of the problems which long-range AA gunners have in dealing with them. You know, for instance, that the target is difficult to recognize, that it can be flying very high and moving very fast. Ships have special range finders and calculating instruments to assist in the control of long-range AA fire. Army long-range gunners have the same sort of thing. Height finders, predictors, and other instruments, all of which help to solve the problem and transmit the information to the guns. And all this is for dealing with aircraft targets at long range. The purpose of the films that will be shown during this course is to teach you how to engage aircraft targets at short ranges, generally inside 2,000 yd, with the close-range weapons. In this case, there's no time to make elaborate calculations or refer to instruments. The aircraft that is in delivers its attack, and gets away out of it in an instant. Attacks are made in quick succession, and you only have a few seconds in which to fire. In that period, you must develop the maximum rate of fire possible. You must concentrate your whole attention on keeping a stream of projectiles peppering the target every moment it is within range. To do this, you must aim instinctively by eye. Remember, the target is close, moving rapidly, at least you know what it is doing, and therefore why you should aim to hit it. With no instruments to delay you, you convert that knowledge into instant action with results which should prove exceedingly unpleasant for the enemy. This kind of shooting at close range targets is called eye shooting. There is nothing new or complicated about eye shooting. These men have just done well. They probably remember their instinct as boys. You were all experts at eye shooting once, though you didn't think of it by that name. Let me remind you. When you were a small boy, there was probably nothing you liked better than pelting people with snowballs. You would lie in wait for your victim, squeezing the ball as hard as possible. Then, when your target came within range, you sized him up, and won scored a direct hit. Your next victim was perhaps the local butcher's boy, trying to beat his own speed record downhill. This shot was bit more difficult. But once more, judging the target's speed and size, you let fly. But the butcher's boy is not standing for that kind of nonsense. He picks himself up and makes a bee-line for you with the obvious intention of knocking your block off. However, you're quite prepared for this and you let him have it straight from the shoulder. This throws him off short and advises you to get away. Now, there wasn't anything very complicated about that, was there? Here's a simple diagram of what you did. This represents you and this the target. You realize that it would take a little time for your snowball to cover the distance between you and the target. And the during that time, the target would travel a certain distance in the direction in which it was pointing. Therefore, instead of aiming here, you aimed off somewhere along that line, depending on how fast the target was going, so the ball and target would meet. This principle has been known and applied instinctively for centuries and is the basis of eye shooting with which we are concerned today. The archer had no difficulty in scoring a bull's eye on a stationary target. Neither did he have difficulty in hitting a moving target. What the archer did with his bow and arrow, you must do with a gun. Aim off a hair and put one in the bag. Don't be disturbed because modern weapons look more complicated. The principle of aiming remains exactly the same. The first important point to grasp is the direction of aim off. Here is the present position of an aircraft flying in this direction. Its future position after a given period of time will be somewhere along this line. Therefore, in order to hit it, we must aim off along this line. If it were flying in this direction, you would aim off along that line. Or this direction, along this line. Or if diving, along this line. And so on for any direction of flight of an aircraft. You may be thinking, "Yes, I can see I shall have to aim off somewhere along the line of flight, but how far along it?" This depends partly on the speed at which the target is moving. The small boy we saw last now instinctively aimed a long way ahead for the fast bicycle, and not so far ahead for the slower one. And consequently scored a hit in each case. If we time these things, we will see more clearly exactly what happened. The projectile takes a certain time to reach the aircraft. This is called time of flight. During the time of flight of a projectile, a fast aircraft will travel a greater distance than a slower one. This is the line of sight to their present position. If one is twice as fast as the other, then during the time of flight of the projectile, it will travel twice the distance. Obviously, therefore, in order to hit the fast one, our projectile will have to travel along that line. Whereas to hit the slow aircraft, it will have to travel along this line. Therefore, the amount of aim-off required to hit the slow one is that much, and the amount to hit the fast one is twice as much. The amount of aim-off is therefore directly proportional to the speed. Twice the speed, twice the aim-off. But the angle at which the target is approaching also affects the amount of aim-off required. Obviously, if the target is coming straight at you, then in order to hit it, you will not have to aim-off tall. This fact was also instinctively appreciated by the small boy, as we saw when his adversary advanced straight at him, and he pelted snowball straight back. So, you can see that when the target is coming straight at you, speed makes no difference. The slow aircraft coming straight at you requires no aim-off. Neither does the fast aircraft, although it is covering twice the distance in the same time. On the other hand, to hit either of these aircraft when not coming straight at you, some aim-off is obviously required. Therefore, the angle at which the aircraft is approaching you is just as important a factor in deciding how much to aim-off as the speed at which it is flying. Summarizing then, the facts that we have established so far are first, that in order to hit a moving target, it is necessary to aim-off somewhere along its line of flight. And second, that the amount of aim-off depends on the speed of the target, and the angle at which it is approaching. You have seen enough now to realize that eye shooting is not black magic. You are merely being called upon to apply to a gun simple principles which you have known all your life.