Menace in a bottle

By Laura Meckler, Deborah Ball and Cassell Bryan-Low

The Wall Street Journal

Liquids may be the new box-cutters.

Take an explosive chemical like nitroglycerin, hydrogen peroxide or hydrazine, all relatively easy to obtain. Pour it into a travel bottle of mouthwash or shampoo. Bring along a blasting cap like those found on a firecracker, about the size of a short pencil. Jury-rig a travel alarm clock or a cellphone to provide a charge strong enough to set off the blasting cap. Even a small explosion could bring down a jet aircraft.

For all the advancements in aviation security since 9/11, the ingredients for deadly explosives could be easily carried through airport checkpoints and onto an airplane -- until yesterday, that is. In the wake of the foiled plot to blow up as many as ten airliners, carriers in the U.S. and Europe suddenly banned shampoos, creams, gels, beverages and other liquids from carry-on luggage.

"This is a huge area of vulnerability," says Clark Kent Ervin, former inspector general at the Department of Homeland Security. Terrorists, he says, "are learning, adapting. They develop countermeasures to our countermeasures. We are reactive, and they are proactive."

Aviation officials have been worried about the danger of explosives for years, and the Transportation Security Administration has tried to shift its focus to address the threat. With all the screening for weapons in carry-on luggage, it may now be easier to blow up a plane than to hijack one.

After the 2001 terrorist attacks, security officials banned box-cutters, scissors and sharp objects that terrorists could use to hijack a plane. The TSA allowed small scissors and tools back in passenger cabins in late 2005 because they were spending too much time confiscating these items, and because it allowed airport security screeners to focus on the hunt for bombs.

In a similar vein, after Richard Reid unsuccessfully tried to detonate a shoe bomb aboard a plane in late 2001, the U.S. Congress banned cigarette lighters from U.S. flights. Now, TSA officials complain that they are spending too much time confiscating 30,000 lighters a day. Matches are allowed, but lighters are not. Mr. Reid tried to use a match -- not a lighter.

To focus on explosives, the TSA has installed 93 "puffer" machines that can detect minute amounts of explosive residue on passengers in 36 airports. The machines also have been installed at London's Heathrow airport, and TSA is rolling them out elsewhere.

The TSA also upped the number of bomb-sniffing dog teams. It added teams that watch passenger behavior and try to assess those who exhibit unusual behavior and facial movements. And it gave screeners special training on how to identify bomb-making components hidden in carry-on bags.

Yet experts say the system remains highly vulnerable to plots like the one broken up yesterday in England. Most carry-on baggage passes through an X-ray machine that can easily detect a gun or a knife with its recognizable shape but can miss a bomb component disguised to look innocuous or a bottle of explosive liquid.

"An ordinary X-ray will not be effective in examining a sealed bottle," says Cathal Flynn, former security chief at the Federal Aviation Administration. Screening mass numbers of bottles that come through checkpoints every day is not possible with equipment now available at the checkpoint, he says.

All checked bags are screened for bombs, using CT scans, and those have been considered for carry-on bags, but they are typically very large and would eat up valuable square footage at the checkpoint.

The TSA is planning airport trials with an advanced scanner made by Rapiscan Systems, a unit of OSI Systems Inc., Hawthorne, Calif., which enhances the detection of explosive material. The scanner uses Quadrapole Resonance, a radio-frequency technology that can detect certain explosives in liquids, as well as plastic and sheet explosives, and explosives that might be distributed in packets throughout a piece of luggage and made to resemble innocuous items. The government expects to test the machines at three or four U.S. airports, but they are expensive -- $160,000 each vs. about $35,000 for a basic X-ray.

Another technology that hasn't been deployed by the government would specifically address the threat of liquid in bottles. In the mid-1990s, a small company called Quantum Magnetics, now owned by General Electric Co., began developing a machine that can detect liquid explosives inside bottles. It got some attention in the wake of a 1995 terrorist plot, but has yet to be rolled out in airports.

Dangerous chemicals are easily available. One chemical that has concerned authorities is triacetone triperoxide, known among them as the "Mother of Satan" of explosives because it is so unstable. It is used commonly among suicide bombers in the Middle East and has shown up in a growing number of domestic plots, including in Phoenix where a drug investigation turned into a terrorism probe when authorities found TATP in an apartment there.

Experts say a small amount of explosive material could be devastating. "It may not take a huge blast," says Suraj Lakhani, a researcher on counterterrorism at Royal United Services Institute, a think tank that advises the British government on security issues. "If the person detonating [an explosive] sat near a window or near the fuselage, it could cause a big enough hole to bring the plane down."

Even liquor and matches could be used to start a fire onboard. But aviation and security experts say that as long as airline crews are able to quickly detect and fight a fire in the cabin, it would be difficult for a terrorist to spark a catastrophic blaze. Flight attendants are trained to use portable oxygen and hand-held fire extinguishers at the first sign of a fire, and passenger seats are made of material that only ignites at high temperatures.


Liquid explosives haven't been used much because they are notoriously difficult to transport and can be highly unstable. "The chances of [the explosives] going off while walking around the airport or even when leaving the house is pretty great," says John Chase, a security expert at Kroll Inc., a risk-consulting group and a unit of Marsh & McLennan Companies, Inc.

Yet terrorists have used explosive chemicals on planes before. The latest plot wasn't unimaginable; it reminded several aviation experts of an al Qaeda plot to bomb 11 U.S. passenger jets over the Pacific that was uncovered in the Philippines in 1995. Codenamed "Bojinka," the Serbo-Croatian word for "explosion," the plot also included the assassination of Pope John Paul II during a visit to Manila and crashing a plane into the Central Intelligence Agency's headquarters in Virginia.

Police in Manila stumbled across the conspiracy when they responded to a fire at an apartment rented by Abdul Hakim Murad and Ramzi Yousef, who was later caught in Pakistan and convicted for the 1993 World Trade Center bombing. They found bomb-making materials in a sink and a laptop computer full of coded information. The mastermind of the Bojinka plot -- Khalid Shaikh Mohammed -- later went on to orchestrate the Sept. 11 attacks in the U.S. He was captured in Pakistan in 2003.

In what was believed to be a test run for the Bojinka plot, Mr. Yousef used a liquid bomb on a flight from Manila to Tokyo. He used a stable form of liquid nitroglycerin carried in a bottle labeled as contact lens solution, using cotton as a stabilizer. The device was placed in a life-jacket pouch under a seat before he disembarked during a layover. The bomb exploded on the second leg, killing one passenger but the plane was able to land.

At the time, some airports barred passengers from taking liquids onboard planes but relaxed the rules after several months.

--Lynn Lunsford, Gary Fields, Jonathan Karp and Kathryn Kranhold contributed to this article.

Write to Laura Meckler at laura.meckler@wsj.com, Deborah Ball at deborah.ball@wsj.com and Cassell Bryan-Low at cassell.bryan-low@wsj.com