U.S. Flights Vulnerable to Lagging Security

Despite the grim and growing record of anti-American terrorism, placing a bomb on a U.S. airliner is still easier than getting either a gun or a knife on board, senior U.S. counter-terrorism officials said Friday.

And portable missiles, from which commercial aircraft are virtually defenseless, represent a whole new category of threat.

Moreover, while federal officials generally have assumed that the threat level for American planes was low, terrorists have a chillingly high batting average against the world’s airliners. Since 1969, one-third of all such bombing attempts have achieved some level of success. According to Rand Corp. specialist Karen Gardela, at least 22 of 65 bombings have resulted in casualties, ranging from a handful of deaths to more than 300.

Yet U.S. airports and airlines have not fully implemented the tactics or advanced technologies that government and private experts say would be necessary to improve the odds against attack.

From employing bomb-sniffing dogs and new vapor trace particle detectors capable of spotting lightweight, easily hidden plastic or liquid explosives to making structural improvements in cargo bins, both government and industry have been slow to impose the cost and inconvenience associated with greater safety.

Indeed, while intelligence experts repeatedly have warned that the danger of anti-American terrorism is growing, the U.S. security system to a significant degree remains tilted toward the past--focusing its toughest measures on potential hijackers and drug mules in the passenger cabin rather than terrorist bombs in the cargo bay.

“The underbelly to security in aviation is just that--the underbelly, the cargo area,” said William E. Baker, a former senior FBI official who headed the U.S. investigation of the 1988 bombing of Pan Am Flight 103 over Lockerbie, Scotland, which claimed 270 lives. Technology comparable to that used in screening passengers for firearms and other weapons has not yet been deployed to protect cargo holds, he noted.

“We feel particular frustration because 95% of the new technology is American-made,” said a senior counter-terrorism official.

Investigators continued to emphasize Friday that they do not yet know why TWA Flight 800 disintegrated over the coast of Long Island on Thursday evening, killing all 230 people aboard. Officials cautioned that they do not yet have concrete evidence pointing either to terrorism or mechanical failure.

Whatever the cause of the Flight 800 tragedy, however, it has opened a window on the state of security in the U.S. air travel industry. And the evidence seems clear that, while improvements have been made in recent years, the methods used to protect planes in the United States still lag behind both the state of the art and the systems already deployed in some European countries.

Citing a need for a reexamination, Tim Neale, spokesman for the Air Transport Assn., which represents all U.S. passenger and freight carriers, said Friday that the association had launched a review even before the TWA disaster to assess “whether things are changing here in the United States--and whether we need to be doing anything differently.”

Why does the United States lag? The answer blends concern about costs, a laborious decision-making process, fear of public impatience and a sense that the threat is greater overseas. There is also the sheer size of the U.S. industry.

U.S. scheduled air carriers moved 544.3 million passengers last year, and the 1996 total is expected to top 562.7 million, according to the Federal Aviation Administration. Major airports handle tens of thousands of pieces of luggage, cartons of cargo and sacks of mail each day--almost always under severe time pressure.

Giving each item and passenger individual attention--as does El Al, the Israeli national airline, for example--would be a Herculean task.

Yet experts said the sophistication of technology available to terrorists far surpasses the ability to cope of the security systems employed at many U.S. airports.

One deadly version of plastic explosive, for instance, can be rolled into the thickness of three sheets of typing paper and is difficult to detect even when conventional security systems are primed to look for it.

Metal detectors and X-ray machines, the most common airport security devices, mainly track other forms of weapons such as guns and knives. “It’s a common fallacy that all metal detectors and X-ray machines will pick up explosives. Some might, but some won’t,” one official said.

More difficult to place on board are bomb detonators, wiring and timers because they contain components that are more readily detected by existing systems. For that reason, instead of trying to plant a fully assembled bomb, some terrorists have carried the various parts on board jetliners separately and assembled the deadly devices in lavatories.

Although no system is foolproof, a combination of approaches would increase the chances of intercepting explosives, experts said.

The most effective equipment includes the CTX 5000, which was adapted from CAT-scan medical technology and is capable of looking at pieces of luggage in three dimensions and in thin cross-sections. Another device, the so-called vapor trace particle detector, can suck vapor from inside a bag through seams or handle openings and analyze it for tell-tale evidence of explosives.

When used in combination, new enhanced X-ray devices and the computer-aided tomography (CAT) used in a CTX 5000 can identify suspicious items, which a vapor trace particle detector then can examine without the need to open a bag.

Test runs in several cities, including Los Angeles in 1994 and an ongoing test in Atlanta during the Olympics, have concluded that the CTX 5000 provided “unparalleled detection capability for all types of explosives in many configurations,” according to FAA documents.

Although the technology is American, the FAA has not required that either device be deployed nationwide. After additional tests ending in 1997, the FAA is scheduled to decide what to do.

The technology has been slow to take hold in part because earlier versions of the devices yielded so-called “false-positive” readings, leading security personnel to pull out many bags that turned out to be harmless. The machines could not tell the difference between the nitrogen traces given off by some explosives and, for example, wool sweaters that also have a nitrogen complex.

“Over the last 18 months to two years, the machines have gotten much better, as have the people who used them. They have to be well-trained,” a U.S. expert on aviation technology said.

A State Department specialist said he is not aware of any U.S. airports where the vapor trace particle detectors are used.

Thirty-one airports in the United States and Puerto Rico have bomb-sniffing dogs, all trained at Lackland Air Force Base in San Antonio, according to a Lackland spokesman. But FAA spokesman Les Dorr said they “are not routinely used to sniff baggage.” They can be used if there is a specific reason--what appears to be a suspicious piece of luggage. “The decision to use them is made at each airport,” Dorr said.

“Dogs can be extremely good and often better than many machines, but unlike a machine that you can turn on and off, you don’t know when a dog is working and when it isn’t. A dog’s nose is an extremely sensitive thing,” a senior counter-terrorism official said.

Since the bombing of Flight 103 over Lockerbie, the FAA has implemented 38 steps to improve civil aviation. They include placing federal security managers in 19 of the largest U.S. airports and liaison officers in 17 overseas locations. Also included is upgraded training for screeners and other security personnel and requiring employment investigations and FBI vulnerability assessments at major terminals.

But those steps are still not enough, experts both in and outside government said. “I would not be surprised if a bomb were on board [Flight 800]. Civil aviation security is more effective than it used to be, but it is still not infallible,” said Moses Aleman, a longtime FAA security official who now is president of AVSEC Inc., an aviation consulting firm in Washington.

“There are always vulnerable areas. Technology also has a hard time keeping up with terrorist groups.”

Times staff writer David Willman and researchers D’Jamila Salem-Fitzgerald in Washington and Lianne Hart in Houston contributed to this story.