No Simple Solution for Luggage Checks

Times Staff Writers

With no effective mechanisms in U.S. airports to detect liquid explosives, federal security officials are confronting a difficult choice: Wait for a technological breakthrough, or permanently impose limits on passenger luggage that would be unpopular among travelers and airlines.

The threat of liquid explosives -- underscored by the disruption of a suspected terrorist plot in Britain on Thursday -- has been known to security agencies for more than 10 years and exposes the vulnerability of U.S. aviation security systems today.

Because of bureaucratic conflicts and other security priorities, no technology has emerged to detect possible liquid explosives in the screening process at airports.

Some are now questioning whether airline passengers should be forced to cut back permanently on the amount of luggage they can carry onto flights to allow easier searches by hand. That issue, which is likely to be debated in the months ahead, is the latest test of travel convenience versus security in the post-Sept. 11 world.


“What needs to be done is pretty simple: You can’t have carry-on bags, and you can’t be in the terminal unless you’re going to fly,” said Joseph J. Trento, coauthor of “Unsafe at Any Altitude,” an upcoming book on aviation security.

A major hurdle in imposing such rules is resistance from passengers and the financially strapped airlines, which are loath to lose more business, Trento and other experts say.

“There’s a tension between the security preference, which would be smaller [carry-on] bags, and the traveling public and airlines,” said U.S. Navy Rear Adm. Cathal L. Flynn, a former associate administrator of civil aviation security for the Federal Aviation Administration. “The debate goes back years.”

It is more difficult to detect objects in larger bags, which also take longer to search, and Flynn said permanent limits on carry-on luggage should be considered.


But he warned that those steps could put more pressure on other parts of the system.

Limiting carry-ons means “more bags going into the checked-baggage screening, and that is, in some instances at peak loads, already at the point of being overwhelmed,” he said.

Higher costs and the need for more manpower also complicate the hunt for elusive materials, such as the components of a liquid bomb, said Scott D. Bates, a lecturer at the National Defense University.

Security officials could start inspecting bags by hand instead of screening them, but the ensuing delays would require redesigning terminals and adding extra aviation security personnel -- now capped by Congress at a maximum of 45,000 nationwide.


Aside from tightening restrictions on travelers, there are technological security options, but they have been slow in coming.

Although there are machines that can detect liquid explosives -- the Department of Homeland Security reportedly has tested several -- they are not used at U.S. airports.

Machines that can detect traces of explosive materials are in 33 airports nationwide but are only used when a passenger has been selected for secondary screening.

Bureaucratic red tape within Homeland Security and the administration’s funding priorities are often cited by critics as reasons for the lack of progress on developing better detection systems or getting them into use.


In 2003, the Transportation Security Administration redirected more than half of the $110 million it had allocated for research and development to pay for screeners, according to Cathleen A. Berrick, the Homeland Security and Justice director at the Government Accountability Office.

In August 2005, a reorganization by Homeland Security Secretary Michael Chertoff moved oversight of TSA research projects from the aviation agency to his department’s Science and Technology Directorate, which had been widely criticized for its lack of direction and productivity.

“They have all sorts of mandates and money to find and deploy the very best technology available,” said Michael Greenberger, director of the Center for Health and Homeland Security at the University of Maryland in Baltimore. Yet, “it is a completely opaque and seemingly inert part of the department.”

Homeland Security spokesman Russ Knocke said that in announcing the department’s reorganization, Chertoff “made very clear we were going to drive our organization and policies by risk, and TSA is no different.”


“Not long ago, TSA made the decision to allow small scissors on airplanes,” Knocke said. “That allowed screeners to focus on looking for items of truly significant consequences like explosives, including liquids, and equipment like the detonators needed for that equipment.”

Knocke noted that the department had invested $732 million this year on aviation-explosives detection.

One factor in the slow response to security concerns has been the TSA’s relative youth, some observers say. The aviation security agency was formed two months after the attacks of Sept. 11, 2001, and immediately faced a series of sweeping mandates from Congress that left little time for research.

Berrick, the GAO director, said that only in the last year had the aviation agency been able to branch out and begin addressing a wider range of threats.


One project initiated last fall involves training dogs to detect TATP -- the peroxide-based explosive thought to be part of the suspected airline plot in Britain -- said Jimmie C. Oxley, a chemistry professor and explosives expert at the University of Rhode Island, which provides training aids to the agency.

The FBI has also been working with the aviation agency on peroxide detection for canines, said Ann Todd, spokeswoman for the FBI laboratory in Quantico, Va.

Some experts say that a reliance on technology or even canine screening is somewhat misguided.

“There’s no way to remove all the risk, and as Americans we don’t like to hear that,” said Bates, the National Defense University instructor.


“We like to think technology can solve anything, but it’s really good old-fashioned intelligence that will make the difference.”



Detecting explosives


The explosive that the suspected terrorists might have used was triacetone triperoxide. Detection technology exists, but it is complicated and time-consuming and is currently not used in airports.

Testing liquids

A button releases a liquid into a testing container. . .

. . .where it fuses with the substance so it can be analyzed.


The liquid then changes color to indicate if the substance is explosive.

Single-use peroxide detectors cost approx. $20 each.


Enhanced X-ray screeners


X-ray detectors compare the density of screened objects to a database of known explosives, including peroxide-based liquids.

Mass density examples (kgm)

Nitroglycerin: 1,600

TNT: 1,700


Black powder: 1,800

C4: 1,640

Ground nuts: 1,400

Nylon: 1,140


Silk/wool cloth: 200


Sources: Technion Research Institute; Guardian Technologies; National Materials Advisory Board; Associated Press