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An eye on airline security technology.

ANYONE WHO HAS been to an airport is familiar with airport security checkpoints and the directions the security personnel give: "Please put your bag on the X-ray conveyor belt. Place your keys and any metal objects in the plastic box, and walk through the metal detector." A generation of travelers has grown accustomed to these directions and probably does not recall air travel without security checkpoints.

In the late 1960s and early 1970s, commercial aircraft hijackings were a common occurrence. In 1973, the Federal Aviation Administration (FAA) instituted security regulations to inspect carry-on bags for bombs and weapons and search passengers electronically before they boarded aircraft. Local police officers were also required to assist with security at airports.

The public accepted these new procedures, and hijackings were successfully reduced.

When x-rayed, weapons such as guns, knives, and hand grenades can be detected in carry-on bags, and metal detectors beep at the presence of any metal object large enough to be a weapon.

X-ray machines and metal detectors are easy to operate. Operators are trained, retrained, and constantly evaluated and tested by the FAA. Each X-ray machine and metal detector is tested daily with an FAA-approved testing device.

Checkpoint security personnel are trained in equipment use, X-ray interpretation, and FAA regulations and emergency procedures.

While the battle against hijackings has been successful, the threat to airlines has evolved from hijackings to terrorist bombings, which are more difficult to prevent.

With a modest amount of explosive, a battery, and a timer, a terrorist can elude the security checkpoint, metal detector, and X-ray machine by placing the improvised explosive device in a checked bag.

In early X-ray machines, explosives appeared as shades of black and gray. Nowadays, X-ray machines enable operators to observe color variations, which identify explosives more readily.

IN ADDITION TO STATE-OF-THE-ART TECHNOLOGY, all US carriers have instituted a specialized security program for international flights from high-risk countries. The program is modeled after the system used by the Israeli airline, E1 A1, and is commonly referred to as a risk analysis system.

This specialized system provides full security for all aspects of each flight, including special procedures for loading cargo, conducting aircraft searches, monitoring catering services, guarding the aircraft, x-raying all baggage, and interviewing each passenger.

Interviews are structured to detect--through profile indicators and observation--passengers who appear suspicious. Suspicious passengers are then given special security treatment, and passengers who do not receive clearance are refused transportation.

While most US carriers introduced the risk analysis system voluntarily, it is now mandated by FAA regulations for all US carriers.

The risk analysis system is expensive and labor intensive. One major US carrier has more than 1,200 security personnel assigned to this program, with an annual cost exceeding $30 million.

While the program provides the highest level of security for US citizens flying on American carriers, it creates a competitive disadvantage for foreign carriers because of the cost and intrusive nature of the passenger questioning.

Thus far, the FAA has not required a similar security program for foreign carriers, including flights carrying large numbers of American citizens to and from the United States.

As mentioned, the risk analysis system includes an in-depth interview of each passenger. During the interview, the security agent checks the passenger's documentation, including ticket, passport, baggage tags, and if necessary, his or her reservation record. Other aspects of the interview and security process cannot be discussed in a public forum.

If a security agent determines that a certain passenger requires special scrutiny, the individual will be body-searched. All carry-on and checked baggage and their contents will be x-rayed. The baggage will be x-rayed empty and thoroughly examined for weapons and other dangerous objects.

With today's X-ray machines, operators are able to enlarge and examine items in detail. Color variation makes it easier to identify explosives.

The security process extends beyond the passenger. In high-risk cities, each aircraft is searched before departure and guarded at all times while it is on the ground. Checked bags are marked (using a confidential code that changes daily), x-rayed, and their position in the cargo hold is noted so the bags can be removed quickly if necessary. Once the checked bag is in the custody of security agents, care and control are maintained until the aircraft departs.

A similar procedure is followed for cargo, catering, and duty-free items. Everything is examined and kept under the care and control of security agents. Cargo and shipping documents are examined. In addition, cargo is delayed 24 hours, and if appropriate, background inquiries are made to determine the shipper's credibility.

Cargo is placed in containers under the supervision of security agents who escort it to the plane. Suspicious cargo may be examined by hand, x-rayed, and subjected to a decompression chamber to resolve security questions.

SECURITY PROCEDURES ARE COSTLY AND time-consuming. Extensive research is underway for technology that will screen carry-on and checked baggage quickly and thoroughly. Ideally, the device would instantly screen a passenger and his or her baggage and be 100 percent successful in detecting weapons or explosives.

This utopian device is not yet available; however, several promising devices are under development and, in some cases, undergoing field testing. Many of the new devices are designed to detect explosive compounds by detecting nitrogen.

Explosives are organic compounds composed of carbon, oxygen, and usually large amounts of nitrogen. Plastic explosives are the choice of terrorists for several reasons. They are stable, oxidize instantly (this avoids the need for a strong containment object like a metal pipe, which is easily detectable under X-ray), are twice as powerful as dynamite, and are as malleable as putty.

Plastic explosives are difficult to detect because they can be shaped into thin sheets and used to line luggage or molded into any configuration.

One of the devices undergoing testing is the thermal neutron analysis (TNA) machine, which is operational at Gatwick Airport outside of London and at Washington Dulles International Airport outside of Washington, DC.

A TNA machine emits low-energy neutrons that interact with the nuclei of atoms inside the baggage. These interactions produce gamma rays, which in turn detect the nitrogen in explosives. The TNA system also includes add-on X-ray machines that are used to quantify suspicious items detected by TNA in baggage.

While the TNA machine holds promise, it is slow, extremely large, heavy (14 tons), and costs approximately $1 million per machine. It also has an unacceptable high false alarm rate. In addition to these problems, several machines are required to handle two or three flights for only one carrier at one airport, making space and cost prohibitive factors, especially when many US carriers have ceased operations and others are in bankruptcy.

Airlines are not the targets of terrorists. They are merely surrogates that are easily accessible to terrorists protesting government policies. Because of this, suggestions have been made to require government funding of explosive detection devices. This idea, however, does not appear to be feasible at this time.

Public Law 101-604 requires that the FAA undertake an intensive review of threats to civil aviation and have new equipment and procedures to meet the technological challenges presented by terrorism in place at all major airports by November 1993. This is a formidable task, and development and evaluation of other devices is underway.

One of these devices is the fast neutron analysis (FNA) system. It is more costly than the TNA system and is based on a different source for detecting explosives. Several different concepts of this system are under development in the United States and abroad.

Another system is the pulsed fast neutron analysis (PFNA) system. It is similar to the FNA, except that a pulsed beam of neutrons is used to detect the explosive material.

Thus far, only the feasibility of the PFNA has been determined. Considerable research and testing are required before a prototype machine is available. This is also a large and costly machine and will not be available for five to seven years.

Other technology based on nuclear-based explosive detection systems would include nuclear resonance absorption, associated particle production, and pulsed neutron backscatter systems. All these systems are in the early stages of development, and their capability and feasibility are unknown at this time.

Other technology that holds more immediate promise are vapor detection systems and what is commonly referred to as enhanced X-ray detection systems. Vapor detection systems are in use at some German airports and in US government installations, both stateside and abroad.

This system is based on gas chromatography, which samples molecules from air samples obtained from baggage. A collector, about the size of a mailbox, sucks in an air sample from baggage. The collector is then inserted into a 4-foot-high console that mixes the air sample with ozone in a chamber. By a process called chemiluminescence, a weak light is produced if an explosive is present. The analysis of the air sample takes only a few seconds.

Other vapor detection systems in use or under development are gas chromatography, ion mobility spectrometry, two-stage mass spectrometry, and fluoroimmunoassay.

The enhanced X-ray detection systems also hold promise for more immediate use in an airline or airport environment. The current X-ray scanners have been used for many years to detect weapons and less sophisticated explosive devices. More advanced systems are already in use or under development. These include dual- or multienergy scanners, backscatter X-rays, and computerized tomography systems.

Another dual-energy X-ray system undergoing testing in an airport is based on a system using medical instrumentation technology. This technology is tied to high-tech computer capability that permits a fast analysis of baggage examined by the machine. The data processing is equivalent to approximately 150 desktop computers.

Another promising realm for applying technology to airline security is the hardening of aircraft. If an aircraft can be designed to withstand a minimum level of explosive material, the technology to detect such material in checked baggage, cargo, or carry-on baggage will be considerably enhanced and simpler to develop.

For example, a machine that detects 1 pound of explosive material will have a high false alarm rate and may not always detect 100 percent of such material. If the aircraft could be hardened to withstand 2 or 3 pounds of explosive material, the detection rate would increase substantially.

Changing the design of aircraft is a long-term proposition. Developing baggage containers that could withstand explosive devices, however, could be undertaken in the short term. Such containers would have to be lightweight and reasonable in cost. Protecting the integrity of the aircraft and passengers in flight is a topic that requires more focus, both from the Federal government and the airline industry.

Airline security is complex because the nature of the industry is complex. In 1991, 1.2 billion passengers around the world traveled on airlines. When considering baggage carried by each passenger and cargo boarded on the aircraft, as well as catering and all the other activities necessary for the departure of each flight, the complexity of airline security is evident.

Ensuring the security and safety of each flight is a monumental undertaking that requires both human and technological expertise. During the past several years, the US airline industry has worked closely with the government to ensure that the best equipment and procedures are used to create and maintain the highest level of security for passengers. This effort will continue because of the commitment by both the airline industry and the government.

Homer A. Boynton is managing director of corporate security for American Airlines in Dallas. He is the chairman of the ASIS Subcommittee on Airports and Airlines.
COPYRIGHT 1992 American Society for Industrial Security
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1992 Gale, Cengage Learning. All rights reserved.

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Title Annotation:Transportation: Screening
Author:Boynton, Homer A.
Publication:Security Management
Date:Jun 1, 1992
Previous Article:Private Investigation Methods and Materials.
Next Article:Keeping the mob at bay.

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