technology, war technology, gun technology, USA Guns

The 120-mm cannon of an M1 tank would be a useful weapon for the U.S. Army to have on just about any combat mission. Unfortunately, at a weight of around 60 tons, it takes a great deal of planning and coordination to get an M1 where it needs to go in the world. An M1 is too large to fit on the Air Force's C-130 transport planes. What's more, a vehicle with more firepower and armor usually requires a more complicated support system. This means more specially trained soldiers to operate it, more technicians to maintain it, more parts, and more and larger shells. Thus, the most powerful equipment is often the hardest to move quickly to the battle zone. There are places the mighty M1 can't reach in time to be effective.

 

Photo courtesy U.S. Army Stryker vehicles position themselves in the town of Samarra, a town northwest of Baghdad, Iraq, December 2003.

The Army's new Stryker project is an attempt to find a workable balance between power and mobility. It's a vehicle system that's built to be as deadly as a tank, as swift as a Humvee and yet mobile enough to be deployed anywhere in the world within 96 hours. In this article, HowStuffWorks explores the thinking behind the Stryker vehicle platform, how it's designed to function in combat and how it fits into the U.S. Army's plans for the future.

Twenty years ago, most people didn't have any idea what C-4 was. Recently, it has become an all-too-familiar term, popping up in newspapers and on television all the time. In October 2000, terrorists used C-4 to attack the U.S.S. Cole, killing 17 sailors. In 1996, terrorists used C-4 to blow up the Khobar Towers U.S. military housing complex in Saudi Arabia. In December 2001, a man smuggled similar material, hidden in his shoes, onto a commercial airliner. C-4 has also been used in many of the Palestinian suicide bombings in Israel and the Israeli-occupied territories.

In this article, we'll find out what this powerful material is and see how it can wreak such destruction.

The Patriot missile system has a remarkable goal: It is designed to detect, target and then hit an incoming missile that may be no more than 10 to 20 feet (3 to 6 meters) long and is typically flying at three to five times the speed of sound. The upgraded Patriot system can also destroy incoming aircraft and cruise missiles.

The Patriot missile system has been deployed in many situations because it is able to shoot down enemy missiles (e.g. Scud missiles) and protect soldiers and civilians from a missile attack. Patriot missile batteries were activated several times in the Iraqi war and were used extensively in the 1991 Gulf war. In this article, we will look at the technology that allows a Patriot missile to accomplish its goal.

Like the Stinger missile and the Sidewinder missile, the Patriot is a guided missile. However, the Patriot is somewhat more sophisticated. In both the Stinger and Sidewinder missiles, the infrared seeker is sensitive to engine heat. A human being is responsible for finding and identifying the target, appropriately aiming the missile so that the its heat-seeking eye can lock onto the target, and then firing the missile.

A Patriot missile, instead, depends on radar. The Patriot missile system uses its ground-based radar to find, identify and track the targets. An incoming missile could be 50 miles (80.5 kilometers) away when the Patriot's radar locks onto it. At that distance, the incoming missile would not even be visible to a human being, much less identifiable. It is even possible for the Patriot missile system to operate in a completely automatic mode with no human intervention at all. An incoming missile flying at Mach 5 is traveling approximately one mile every second. There just isn't a lot of time to react and respond once the missile is detected, making automatic detection and launching an important feature.

While the Stinger is a shoulder-launched weapon and the Sidewinder launches from aircraft, Patriot missiles are launched from Patriot missile batteries based on the ground. A typical battery has five components:

• The missiles themselves (MIM-104)
• The missile launcher, which holds, transports, aims and launches the missiles (M-901). This part is necessary because each missile weighs almost 1 ton.
• A radar antenna (MPQ-53 or MPQ-65) to detect incoming missiles.
• An equipment van known as the Engagement Control Station (ECS) houses computers and consoles to control the battery. (MSQ-104)
• A power plant truck equipped with two 150-kilowatt generators that provide power for the radar antenna and the ECS.

 

Image courtesy Raytheon Company Copyright © 2002 Click here for a larger version of this diagram.

Since a Patriot missile battery can have up to 16 launchers, and there are also spare missiles to re-supply the launchers as missiles are fired, you can see that deploying a Patriot missile battery is not a small endeavor. Each launcher is roughly the size of a tractor-trailer rig, as is the ECS and the power supply truck. There are also operating personnel, technicians, support personnel, fuel for the generators, security forces to protect the battery, etc. This article describes a "convoy of about 300 vehicles, which included infantry forces, tanks and Marines" to move a Patriot missile battery to the front lines and make it operational. The deployment of Patriot missiles is not a decision made lightly.

 

Photo courtesy U.S. Department of Defense

 

In the following sections we will look at each of the different components, and then how the system operates as a whole.

 

 

The Stinger missile is something that appears in the news every time there is an armed conflict involving United States forces. It also appears after certain airline accidents -- the one involving TWA flight 800 is a recent example. The reason we hear so much about the Stinger in these contexts is because the Stinger missile is an extremely effective weapon for shooting down aircraft. The missile uses an infrared seeker to lock on to the heat in the engine's exhaust, and will hit nearly anything flying below 11,000 feet.

In this article, you will have a chance to learn about the Stinger missile. What sorts of aircraft can it hit? Why is it so effective? You will also learn about the role of the Stinger missile in Afghanistan.

All of the expensive technology that goes into a fighter jet, attack helicopter or bomber wouldn't be much use on the battlefield without any ordnance. While they're not as expensive or complex as the military vehicles that carry them, guns, missiles and bombs are the end technology that finally gets the job done in combat. And most of today's missiles and bombs are pretty impressive aircraft in their own right. Smart weapons don't just sail through the air; they actually find their own way to the target.

Sidewinder Image Gallery 

 

In this article, we'll look at one of the oldest and most successful smart weapons in the U.S. arsenal, the legendary AIM-9 Sidewinder missile. As we'll see, the small and simple Sidewinder is a highly effective combination of electronics and explosive power, brought together with incredible technical ingenuity.

On March 11, 2003, the United States Air Force tested one of the largest conventional bombs ever built. It is called the MOAB -- Massive Ordnance Air Burst. It is a bomb designed to destroy heavily reinforced targets or to shatter ground forces and armor across a large area.

 

 

Photo courtesy U.S. Department of Defense MOAB is currently the largest conventional bomb in the U.S. arsenal.  See more MOAB pictures.

 

In this article, we'll examine this new high-powered bomb and see where it fits into the U.S. arsenal.

A dirty bomb is an explosive designed to spread dangerous radioactive material over a wide area. When people hear "bomb" and "radioactive" in the same sentence, their minds jump to nuclear war pretty quickly. But it turns out that a dirty bomb's primary destructive power would probably be panic, not radiation damage.

A dirty bomb is much closer in power to an ordinary explosive than it is to the widespread destructive force of a nuclear bomb. But the fear of contamination could be debilitating, in the same way that 2001's anthrax scare in the United States terrorized much of the American populace, even though only a few people were infected.

In this article, we'll find out what dirty bombs are and what they do. We'll also explore what might happen if one actually went off in a public area, and consider some of the consequences of this sort of attack.

Conceptually, a dirty bomb (or radiological dispersion bomb) is a very simple device. It's a conventional explosive, such as TNT (trinitrotoluene), packaged with radioactive material. It's a lot cruder and cheaper than a nuclear bomb, and it's also a lot less effective. But it does have the combination of explosive destruction and radiation damage.

High explosives inflict damage with rapidly expanding, very hot gas. The basic idea of a dirty bomb is to use the gas expansion as a means of propelling radioactive material over a wide area rather than as a destructive force in its own right. When the explosive goes off, the radioactive material spreads in a sort of dust cloud, carried by the wind, that reaches a wider area than the explosion itself.

The long-term destructive force of the bomb would be ionizing radiation from the radioactive material. Ionizing radiation, which includes alpha particles, beta particles, gamma rays and X-rays, is radiation that has enough energy to knock an orbital electron off of an atom. Losing an electron throws off the balance between the atom's positively charged protons and negatively charged electrons, giving the atom a net electrical charge (the atom becomes an ion). The free electron may collide with other atoms to create more ions. (See How Atoms Work for more information on subatomic particles.)

If this happens in a person's body, the ion can cause a lot of serious problems, because an ion's electrical charge may lead to unnatural chemical reactions inside cells. Among other things, the charge can break DNA chains. A cell with a broken strand of DNA will either die or the DNA will develop a mutation. If a lot of cells die, the body can develop various diseases. If the DNA mutates, a cell may become cancerous, and this cancer may spread. Ionization radiation may also cause cells to malfunction, resulting in a wide variety of symptoms collectively referred to as radiation sickness. Radiation sickness can be deadly, but people can survive it, particularly if they receive a bone marrow transplant.

In a dirty bomb, the ionizing radiation would come from radioactive isotopes (also called radioisotopes). Radioactive isotopes are simply atoms that decay over time. In other words, the arrangement of protons, neutrons and electrons that make up the atom gradually changes, forming different atoms. This radioactive decay releases a lot of energy in the form of ionizing radiation. (See How Nuclear Radiation Works for details on radiation and radioactive isotopes.)

We're exposed to small doses of ionizing radiation all the time -- it comes from outer space, it comes from natural radioactive isotopes, it comes from X-ray machines. This radiation can and does cause cancer, but the risk is relatively low because you only encounter it in very small doses.

A dirty bomb would boost the radiation level above normal levels, increasing the risk of cancer and radiation sickness to some degree. Most likely, it wouldn't kill many people right away, but it could possibly kill people years down the road.

Anyone who's been through a prolonged power outage knows that it's an extremely trying experience. Within an hour of losing electricity, you develop a healthy appreciation of all the electrical devices you rely on in life. A couple hours later, you start pacing around your house. After a few days without lights, electric heat or TV, your stress level shoots through the roof.

 

An e-bomb would destroy most electrical machines in its path.  See more e-bomb pictures.

But in the grand scheme of things, that's nothing. If an outage hits an entire city, and there aren't adequate emergency resources, people may die from exposure, companies may suffer huge productivity losses and millions of dollars of food may spoil. If a power outage hit on a much larger scale, it could shut down the electronic networks that keep governments and militaries running. We are utterly dependent on power, and when it's gone, things get very bad, very fast.

An electromagnetic bomb, or e-bomb, is a weapon designed to take advantage of this dependency. But instead of simply cutting off power in an area, an e-bomb would actually destroy most machines that use electricity. Generators would be useless, cars wouldn't run, and there would be no chance of making a phone call. In a matter of seconds, a big enough e-bomb could thrust an entire city back 200 years or cripple a military unit.

The U.S. military has been pursuing the idea of an e-bomb for decades, and many believe it now has such a weapon in its arsenal. On the other end of the scale, terrorist groups could be building low-tech e-bombs to inflict massive damage on the United States.

In this edition of HowStuffWorks, we'll examine the basic concept behind e-bombs, and we'll take a look at some major bomb technologies.

Tomahawk cruise missiles frequently appear in the news because they are the U.S. weapon of choice for a variety of quick-strike operations. With all of the missiles in the U.S. arsenal, have you ever wondered why cruise missiles seem to come up so often?

Cruise Missile Image Gallery 

 

In this edition of HowStuffWorks, we will look at cruise missiles so that you can understand what they are, how they operate and why they are ideal for certain scenarios.

The basic concept of a bomb could hardly be simpler. A conventional bomb consists of some explosive material packed into a sturdy case with a fuze mechanism (yes, that's fuze, not fuse). The fuze mechanism has a triggering device -- typically a time-delay system, an impact sensor or a target-proximity sensor -- which sets the bomb off. When the trigger goes off, the fuze ignites the explosive material, resulting in an explosion. The extreme pressure and flying debris of the explosion destroys surrounding structures (see How Grenades Work for information on explosives and fuzes).

 

Photo courtesy U.S. Department of Defense An F-15 Strike Eagle drops GBU-12 laser-guided smart bombs. See more smart bomb pictures.

A "dumb bomb" is a bomb with only these elements, dropped from an airplane (such as the B-2 bomber). The bomb is considered "dumb" because it simply falls to the ground without actively steering itself. Needless to say, it's some feat hitting a target precisely with this type of weapon. A bomber might have to drop dozens, or even hundreds of dumb bombs to take out a target effectively.

"Smart bombs," by contrast, control their fall precisely in order to hit a designated target dead on. In this article, we'll find out how the major types of smart bomb accomplish this.

Smart Bomb Basics
A smart bomb is essentially an ordinary dumb bomb with a few major modifications. In addition to the usual fuze and explosive material, it has:

• an electronic sensor system
• a built-in control system (an onboard computer)
• a set of adjustable flight fins
• a battery

When a plane drops a smart bomb, the bomb becomes a particularly heavy glider. It doesn't have any propulsion system of its own, like a missile does, but it does have forward velocity (by virtue of being dropped from a speeding plane). It also has flight fins that generate lift and stabilize its flight path.

 

Photo courtesy U.S. Department of Defense This smart bomb, the Enhanced Guided Bomb Unit-27, has an optical sensor system, an onboard computer, adjustable flight fins and a battery that powers everything.

The control system and adjustable fins give the bomb a way to steer itself as it glides through the air. While the bomb is "in flight," the sensor system and control system track the designated target on the ground. The sensor system feeds the control system the relative position of the target, and the control system processes this information and figures out how the bomb should turn to steer toward the target.

To actually turn the bomb, the control system sends a message to actuators that adjust the flight fins. These fins work the same basic way as the various flaps on an airplane. By tilting the fins in a particular direction, the control system increases the drag acting on that side of the bomb. As a result, the bomb turns in that direction. (See How Airplanes Work for more information).

This adjustment process continues until the smart bomb reaches its target, and the fuze mechanism sets off the explosive. Smart bombs generally have proximity fuzes, which set off the explosive just before the bomb reaches the target, or impact fuzes, which set off the explosive when the bomb actually hits something.

The main difference between the different types of smart bomb is how the sensor system actually "sees" the target in the first place. We'll look at how smart bombs have done this in the past in the next section.