FAA Scientists Strive to Strike Fear in the Hearts of Terrorists

Dan Riley’s desk is cluttered with about a dozen hand grenades.

The desk is in a back corner of a modest, concrete-block building, tucked away behind a stand of scraggly pines. There, in their quiet enclave, six miles inland from the raucous bustle of the glittering Boardwalk casinos, Riley and his eight cohorts match wits with international terrorists.

The challenge for these scientists of the Federal Aviation Administration’s Aviation Security Branch is to find better, more efficient ways to protect the more than 400 million passengers who board airliners in the United States each year from those who would kidnap, kill, maim and destroy for politics or profit.

Civilian jetliners make inviting targets--filled with unarmed, innocent, unsuspecting victims. There is a guarantee of worldwide publicity for anyone who attacks such a plane in an effort to further a cause or collect a ransom.

It is up to Riley and the others from the Security Branch at the 5,000-acre FAA Technical Center here to make those aircraft, and the people in them, less vulnerable--to foil hijackers and terrorists who would destroy a plane with weapons or explosives such as the grenades Riley keeps for study at his desk.

It is a task complicated by the fact that most of the security systems must be paid for and used by commercial airlines, private businesses that want to keep the need for security, and the means used to assure it, as unobtrusive as possible.

To accomplish their task, the Security Branch is spending $12 million a year, pushing technology to the limits and relying on some old-fashioned logic. To improve its understanding of terrorists’ methods, the agency even blows up sections of airplanes in re-created attacks.

Last month, after years of secrecy, the agency leaked a few details about two new pieces of bomb-detection hardware--a neutron-radiation device that can scan baggage and cargo to detect the nitrogen compounds present in every known explosive, and “mechanical dogs” that can sniff out the minute traces of vapor emitted by such compounds.

Now, for the first time, the scientists who are testing these and other systems are talking publicly about their research with infrared detectors that can find concealed, non-metallic weapons people are carrying; dual-energy and high-dose X-ray machines that can ferret out such weapons in baggage and bulk cargo, and motion detectors that can catch terrorists attempting to sabotage or hijack planes.

They also talked about a plan, called Least Risk Analysis, to be used if the systems fail.

In recent years, a new urgency has been brought to the work the Security Branch began in the late ‘70s after a locker bombing at New York’s La Guardia Airport that killed 11 and injured 70.

The apparent bombing over the Atlantic in June, 1985, that killed all 329 aboard an Air India flight from London to Montreal was followed in April, 1986, by a bombing aboard a Trans World Airlines plane en route from Rome to Athens that claimed four lives. A month later, there was a bomb explosion on an Air Lanka jet at an airport in Sri Lanka that killed 20 people boarding the plane.

Chris Seher, assistant manager of the Security Branch, said these and dozens of other incidents have shown that there are five basic ways a terrorist can sneak weapons or explosives aboard an aircraft: on some passenger’s person, in carry-on luggage, in checked baggage, in air cargo and on the person of unauthorized personnel gaining access to the plane while it is on the parking apron.

“There’s no one technique out there that’s going to work on all of those avenues to an airplane,” Seher said, noting that systems suitable for inspecting luggage and cargo may not be suitable for checking people, and vice versa.

“X-ray is absolutely great for screening a bag, but we’re not going to be allowed to X-ray all people who walk on board an airplane, certainly not with the dose levels needed to find explosives,” he said. “People make two, three four connections a day. You’re not going to give them four X-rays a day.”

On the other hand, he said, infrared sensors that can safely locate non-metallic objects on people cannot penetrate some baggage and cargo containers.

The detection devices most familiar to airline passengers are probably the metal detectors, shaped much like a standard, rectangular door frame, through which passengers must pass before they are permitted to board an airplane.

“They’re designed to detect things like handguns and knives, and they work pretty well,” Seher said. “They even detect the Glock 17, the so-called ‘plastic handgun,’ which it really isn’t.”

The Glock 17 has a metal barrel, slide and spring and a metal-lined magazine; the frame and receiver are plastic.

“But there are factual reports out there that there are handguns being developed with even less metal,” Seher said. “People are talking about either all plastic someday, or ceramic.”

Against that day, he said, the Security Branch is funding some research on infrared detection systems that would scan the body with harmless light rays below the visible spectrum, detecting anything abnormal--”anything different than the body image you would get when you walked through with just the normal type of things.

“We hope it could be used in a walk-through portal, like the metal detector,” Seher said. “The question would be the false-alarm rate.”

A remaining concern is explosives carried on the person, especially plastic explosives, which can be molded into any shape and even fabricated into clothing.

“Everything gives off a vapor, including explosives,” Seher said. “Dogs work very well with dynamite and have had some success with other explosives. But plastic and some of the others give off less vapor, and dogs don’t detect them as well.”

Airlines Must Approve

An additional problem is that any of the detection systems used must ultimately win the approval of the airlines. Seher noted that sniffing dogs are hardly the sort of detection system likely to win the hearts, and patronage, of the flying public.

As a result, he said, the FAA is looking at a different type of sniffing device--a “mechanical dog” that promises to detect vapors that are extremely faint--less than one part per million parts of air. It is the vapor-detection system developed by Thermedics Inc. of Woburn, Mass., that inhales the vapors surrounding people and objects and carries them to a chamber that provides a chemical analysis of the fumes.

The Thermedics system--already in use at several U.S. embassies--is scheduled for testing by the FAA in mid-1988.

Another technique employed by airport security people is the use of profiles developed after the careful study of dozens of known and captured terrorists that tell how a potentially dangerous passenger is likely to behave, how he might respond to questions and what he is likely to be wearing.

Seher and other FAA officials declined to talk about the profiles, noting, as others have in the past, that there is simply no advantage in tipping one’s hand to the potential terrorist.

“You know, our best threat against them is what they don’t know about,” Seher said.

“What they don’t know about worries them. . . .

“There are literally thousands of weapons found where people ditch them at airports in ash cans, toilets, you name it,” he said. “They’re not sure how well our systems work and they don’t want to be caught.”

Turning to the subjects of checked and carry-on luggage and cargo--other avenues a terrorist might pursue in an effort to introduce weapons or explosives--Seher talked about X-ray machines, another type of equipment familiar to most airline passengers.

The X-ray machines--rectangular boxes about the size and shape of a refrigerator lying on its side--are positioned beside the metal detectors at most airports. While the passenger is being scanned for metal, baggage is passing through the X-ray machine on a conveyor belt to determine if there is anything dangerous inside. Checked luggage and cargo often undergo similar X-ray inspection.

“It’s a pattern-recognition technique,” Seher said. “The operator can only recognize a pattern he’s familiar with”--guns, knives, grenades, bottles that might contain flammables, and the timing and detonation devices used to set off explosives. “It’s labor-intensive, using video screens monitored by humans, so there are human failings,” Seher said.

He said the FAA is attempting to develop improved training programs “to enhance operator alertness”--a need some critics have voiced publicly in recent years.

In addition, the Security Branch is looking at automated computer software that might be programmed with thousands of recognition points to make it capable of warning the operator to take a closer look.

Machines that X-ray baggage and cargo from two different views to give an operator better perspective have proven effective. A “dual-energy” X-ray under Security Branch development that scans baggage and cargo with twin beams of different intensity gives an operator an improved picture of the composition and thickness of what he is looking at. “High-dose” X-ray machines that can penetrate heavy crating and sheathing are being used to inspect checked luggage and cargo on some high-risk flights today to troubled areas of the world.

Could Check Carry-On Luggage

Because plastics and some other explosives can be molded into apparently harmless shapes, the Security Branch is getting ready to look this summer at devices that bombard objects with neutrons. The neutrons react with nitrogen, the common component of all explosives. Gamma rays produced by this reaction are analyzed by a computer, which would reveal whether explosives are present.

While designed primarily for cargo and checked baggage, some FAA people think the devices could be adapted for carry-on luggage as well.

While the indirect radiation hazard from this process is said to be minimal, it is considered too dangerous to use directly on passengers.

Another technique used to check carry-on and checked luggage is the slow, meticulous hand-inspection system employed by El Al Airlines, a victim of numerous terrorist attacks.

“It works,” Seher said. “But it doesn’t seem a practical solution for the (vast) American domestic market.”

One technique employed by El Al that has attracted Security Branch interest is the so-called “baggage-reconciliation” system, which is scheduled for implementation on overseas flights this December by all U.S. airlines.

Under this system--which employs the theory that most terrorists are not suicidal--checked baggage is placed on a plane only if the person who checked the luggage is also on board the plane.

El Al uses a cumbersome and time-consuming manual method of making the cross-checks; Seher said the Security Branch is attempting to develop a quicker and more efficient computerized technique.

Even if the passengers, hand luggage, checked baggage and cargo have been inspected and cleared, airlines still face the possibility that unauthorized outsiders with weapons and explosives will gain access to planes.

Again largely because of public-relations consciousness, airlines here are reluctant to employ the sort of armed guards, chain-link fences and attack dogs favored for physical security by some nations.

Subtle Security Systems

Here, the physical security systems are more subtle, relying on television cameras and electric eyes. Seher said research work is being done on advanced heat, pressure and motion sensors that could enhance existing systems.

Regardless of the system, the quarry is the same--”the bad guys . . . and the sort of things the bad guys could reasonably be expected to get,” Riley said as he eyed his desk-top collection of grenades--metallic and plastic, ranging in size from a golf ball to a beer can--that are thought to be available to the underworld through international arms merchants.

“Our job is to detect things--abnormalities,” Riley said. “If we don’t know what that abnormality is, we have to find out.”

“And let’s suppose that all our technical equipment has failed, and that an explosive is aboard an aircraft and the aircraft is up in the air,” Seher said.

If the bomb is in a cargo hold, about the only thing to do in most cases is to land at once and evacuate the plane. Most aircraft do not provide on-board crew or passenger access to cargo holds.

But Seher said that if the bomb is in a passenger or crew compartment, people aboard the plane can employ techniques developed by the Security Branch through research called Least Risk Analysis.

Scientists at the Security Branch re-created an attempted bombing of a Braniff Airlines plane on a flight from Washington to Texas in March, 1982, in which the device failed to explode, and the bombing of a Pan American World Airways jet over the Pacific five months later that killed a teen-age passenger whose seat was over the explosive.

Detonations Filmed

Sections of jetliner fuselage similar to those involved in each incident were hauled to the Atlantic City test center and outfitted with seats and dummies. Explosives of the same types and amounts were then detonated in the same positions and the procedures were recorded on film and instruments.

Drawing upon such experiments and the experience and expertise of the FBI and airplane manufacturers, Seher said, the Security Branch has determined where explosives can be detonated aboard a plane with the minimum possible damage to its airframe, propulsion, communications, landing and control systems.

Seher said logic has dictated that the cockpit crew would follow a three-part scenario while heading for the nearest airport: descending to a low altitude and depressurizing the plane so a bomb blast would not cause explosive decompression, lowering the landing gear so “they’d have it down in case they lose that ability later” and placing the explosive in a “least-risk” location.

“It’s classified as to exactly where you would put it on each airplane, but it is almost always . . . at a door,” Seher said. “The thought is that you put suitcases and wet blankets on it to dampen the effect inside. . . . The blast will, in most cases, just take the door out.

“Of course, we hope it never comes to that. . . . “