The Weapons: Inside the High-Tech Arsenal

By Philip Elmer-DeWitt

For years, American military hardware has been the butt of bitter jokes, taxpayer complaints and congressional investigations. To judge by the cost overruns and testing mishaps, the U.S. arsenal seemed to consist of planes that spun out of control, tanks too cumbersome to maneuver and spare parts with Tiffany price tags. What a difference a war makes. Now that U.S. Patriots are chasing down Scuds and laser-guided bombs are nailing targets in Iraq, the once derided weaponry has become the star of the war. Suddenly, everybody is a weapons buff.

For military planners, the apparent success of their high-tech equipment in the early weeks of the battle is sweet vindication. Though Operation Desert Storm still relies in part on armaments of Vietnam War and even World War II vintage, the Pentagon has staked its reputation on its state-of-the-art showpieces. For 40 years, it has pursued a sometimes controversial doctrine that says the best way to counter a potential adversary's superior numbers is with superior technology. Now military experts are watching the payoff with excitement but also apprehension. The high-speed electronics and precision engineering that make the new weapons so effective also make them vulnerable.

The most visible symbol of the U.S.'s technological edge -- those pinpoint strikes on Iraqi targets -- actually represents some fairly straightforward bombing. The key technology is a simple laser detector on the nose of a glide bomb that is electronically linked to adjustable fins in the bomb's tail. All the pilot has to do is point a pencil-thin laser beam at his target and push a button. A stabilizing computer keeps the beam locked in place, freeing the pilot to pitch and roll as necessary to evade enemy fire while the bomb rides along the beam's reflection, flying into the target like a moth to a flame.

The real technological marvels in the U.S. missile array are the sea- launched Tomahawk cruise missiles that smashed Iraqi air-defense systems early in the war. Packed with advanced electronics and several different guidance systems, they are essentially flying computers capable of sailing through the goalposts on a football field from a range of several hundred miles. They can also perform dizzying acrobatics, as witnessed by U.S. reporters who, before they were ousted from Iraq, watched with amazement as a Tomahawk streaked below their hotel windows and made a pair of swooping 90 degrees turns to avoid the Al Rasheed in downtown Baghdad.

The secret of the Tomahawk's precision flying is a two-step guidance system. First, a radar altimeter compares the topography of key landmarks along the missile's flight path with detailed contour maps stored in its computer memory. Then, as the Tomahawk approaches its target, a small digital camera, acting as an electronic eye, compares the view from the nose cone with a library of images prepared from satellite photos. If the missile sees that it is even slightly off course, it makes adjustments.

One of the biggest uncertainties before the war started was how the Patriot system would fare. The antimissile missile is guided by a sophisticated phased-array radar consisting of more than 5,000 radar antenna elements that can detect and track 100 targets at a time and follow any given one far more rapidly than the rotating cone of conventional radar. But the system had never been tested against a Scud.

During the first week of the war, the Patriot performed better than had been expected, hitting 95% of its targets as opposed to the 60% experts had predicted. But the system, which was designed as an antiaircraft weapon and later modified to shoot down missiles, is not infallible. Many of the Scuds that got through last week were actually struck by Patriots but not destroyed. Investigators say part of the problem seems to be that Scuds tend to break up as they re-enter the atmosphere. In at least one case, a Patriot struck the tail end of a disintegrating Scud, leaving the warhead intact to complete its mission.

Another surprise for the allied command is how well its pilots -- and equipment -- are performing at night. One concern had been the efficacy of night-vision goggles, which had been blamed for dozens of crashes over the past decade. These goggles, which are standard issue for ground forces, rely on the same light-gathering technology used in video camcorders to amplify ambient light up to 60,000 times. But pilots flying over Kuwait and Iraq had another window into the darkness. Affixed to F-16s, F-15Es and other attack aircraft is an imaging system called LANTIRN (low-altitude navigation and targeting infrared system for night), which illuminates objects with infrared beams. This system projects the view on a phosphorus screen in the cockpit. Objects appear as yellow-green shapes in an image that resembles a photographic negative.

Should the ground war start, the biggest technological question mark may be the Army's M1 and M1A1 Abrams tanks, the most advanced armored vehicles ever built. The M1 features a 120-mm gun that can fire accurately even while the tank is running over rough terrain, thanks to a built-in ballistic computer and sophisticated stabilizers. Both models carry a chemical fire-suppression system that can put out a flame in a quarter of a second and are shielded by armor plates containing nonradioactive uranium 2 1/2 times as dense as steel. But some specialists fear that the tanks, which rely on computerized controls and finicky electronics, could be undone by desert dust. Another worry: that their gas-guzzling turbine engines could run dry in mid-battle.

Working behind the scenes and above the war zone is the largest fleet of spy satellites ever arrayed. There are at least seven different types of "birds" passing over the gulf, ranging from sharp-eyed Keyhole photo-reconnaissance satellites, which can spot an object the size of a football from 500 miles, to the eavesdropping Magnum, which monitors enemy radio communications using antennas the size of baseball diamonds.

At least one early-warning satellite is parked over the Indian Ocean at all times, using its infrared eye to scour Iraqi territory every 12 seconds for the hot flare of a missile launch. Upon detection, an astonishing split-second relay of signals is set into motion. First, the satellite sends its data simultaneously to an Air Force ground station in Woomera, Australia, and to the U.S. Space Command's Missile Warning Center near Colorado Springs. Computers in Colorado instantly sort through the information, identify individual missiles, project target areas and flash the results by satellite back to the gulf. All this happens in time for air-raid sirens to sound four to five minutes before the missiles complete their seven-minute journey. A new, more direct route may increase the odds of intercepting the Scuds. According to this week's issue of Aviation Week & Space Technology, Patriot batteries are receiving unprocessed alerts directly from the early-warning satellites.

None of this would work were it not for the intricate communication network that now crisscrosses the gulf. This elaborate command-and-control system enables allied generals to coordinate not only the American land, sea and air forces but also those of its coalition partners. The brains of the operation are housed in a government building in Riyadh, where an encrypted book of flight schedules and bombing targets is generated every 24 hours and is broadcast to individual commanders by satellite, microwave and secure telephone lines.

How do the generals keep straight the tens of thousands of details involved in organizing up to 3,000 missions a day? "We have a lot of computers," says Lieut. General Charles Horner, the allied air commander. The exact number of machines is unknown, but a Texas supply house reports that Central Command gave it a rush order last month for 1,300 desktop computers, 1,300 laser printers, 350 laptops, 10 local-area networks and an assortment of peripheral equipment (including dust covers and cleaning kits) with a delivery date of "no later than Jan. 14."

The danger with any endeavor so dependent on advanced electronics and jewel- like engineering is that when such systems encounter unexpected trouble they usually do not just slow down; they crash. The Pentagon has not shown any TV pictures of "smart" bombs flying a perfect path into the side of a camel. But as the Scud hits have demonstrated, mistakes do happen. One aircraft expert says the desert sand has wreaked havoc with the British Tornado jets, lodging in the turbine engine blades and melting into glass. If blades on U.S. jets are faring better, it may be because enginemakers imported tons of Saudi sand for tests several years ago and modified their equipment accordingly.

Another natural phenomenon that might cause trouble is electromagnetic radiation from the sun. Heightened solar-flare activity, expected over the next few months, could disrupt military communications and satellite traffic. Air Force officials have called this issue "too sensitive for comment."

It is still too early to say whether the Pentagon's grand doctrine of fighting superior numbers with superior technology will ultimately prevail. It may yet be possible to foil the world's most sophisticated -- and expensive -- weapons with countermeasures, some of which are literally dirt cheap. They include burning smoke pots to deflect heat-seeking missiles, draping targets with pictures of bomb craters to discourage further attack, and hunkering down in caves and sand dunes to wait out the blitz. In the end, no electronic marvel is going to liberate Kuwait. That is a job that will probably fall to the ultimate biological weapon: the G.I.

With reporting by Sue Butler/Cocoa Beach, Jerry Hannifin/Washington and Lara Marlowe/Dhahran