Their Arrows Will Darken the Sun: The Evolution and Science of Ballistics

Chapter 6. New Technology, New Ballistics

New Technology, New Ballistics Weapons technology progressed rapidly in the second half of the nineteenth century, as we have seen. Innovation and technological advances continued throughout the twentieth century, at a somewhat slower pace, but the development of weapons platforms and integrated weapons systems accelerated, and this explosion (pardon the pun) ofweapons technology continues today. Bigger guns fire more rapidly to longer distances, delivering more devastation from more mobile platforms. Artillery was horse-drawn at the end of the nineteenth century, was mounted in a tank by the mid-twentieth, and became airborne by the end of the twentieth century. The rate of fire and the effective range of automatic and semiautomatic firearms increased, even as these hand-held weapons became lighter to carry. All these developments made the problems associated with weapon aiming more acute. Increased ranges, increased target speed and maneuverability , increased weapon platform speed and maneuverability—all made the fire control problem more difficult to solve. In the first part of this chapter we will examine some of the solutions that were developed, particularly for artillery and for airborne weapons, to assist the delivery of ballistic munitions to their increasingly elusive targets. The twentieth century saw the development of effective rockets. Rocketry changed the game, slowlyat first but then at an increasing pace. In the second part ofthis chapter we will see how rockets work and why their ballistics are different from those of gunpowder projectiles. I end the chapter with a summary of "the end of ballistics": the solution to the increasingly complex ballistics problems at longer and longer ranges that we saw in chapter 5. This solution takes the form of guided munitions, which are far more accurate than ballistic missiles over thousands of miles. The introduction of remote sensing systems combined with computer-controlled navigation and guidance systems means that the longest-range missiles 6 126 WHIZZ! External Ballistics have to solve a different set of problems from those faced by the crew of the Paris Gun, for example. These problems fall outside the field of ballistics, strictly speaking, and so here I will only summarize the key features of guided weapons. FIRE CONTROL The key feature of weapons construction that made fire control both possible and necessary is consistency. If the barrels of two nominally identical guns are different or if the rounds they fire vary in size or charge or shape because of significant manufacturing imperfections, it is impossible to provide accurate methods of fire control. Consistency from one weapon to the next permits the development of aiming devices that can be applied to all the weapons of a given type. Of course, each rifle or artillery piece still has to be individually aimed, but a dedicated aiming device can be adjusted to cover the small variations between weapons (due to barrel wear, for example). This consistency of manufacture, through precision engineering, first appeared at the end of the nineteenth century, and so the same period saw the introduction of effective gun sights, range finders, gunner's quadrants, and other equipment (such as fuze settings) that led to increasingly accurate and effective munitions delivery. In the eighteenth century and earlier, few firearms were provided with sights. There was no point (another pun) because, as we saw in the first part of this book, the internal ballistics were such as to render a firearm weapon intrinsically inaccurate. Muskets were aimed at blocks ofinfantry or cavalry, not at individuals. In the nineteenth century rifles and—later on—artillery were provided with aiming sights. At first these were simply front and rear sights that enabled the shooter or gunner to align the barrel of his weapon with the target. Later still the rear sight became adjustable, so that the weapon could be adjusted in elevation for range, or aimed offtarget in azimuth (i.e., horizontally) to allow for the effects of twist or of crosswind. By the end of the nineteenth century, artillery weapons were provided with sighting telescopes with adjustable mountings. Azimuth and elevation sights were operated independently; the gun crew would include a trainer, who aimed the weapon in azimuth, and a pointer, who was responsible for gun elevation. In the twentieth century, range-finding equipment was introduced— increasingly necessary as ranges got longer. Gunners' quadrants permitted New Technology, New Ballistics 127 the setting of barrel elevation with unprecedented accuracy, optical range finders first appeared, and triangulation techniques were developed, such...