"Terror's deadly, elusive liquid alternative"

Friday, August 11, 2006

Terror's deadly, elusive liquid alternative
BY LOU DOLINAR
Newsday (NY)


Liquid explosives, while not undetectable in all circumstances, are far
easier to conceal than their solid counterparts.

Terrorists have a broad smorgasbord from which to choose, ranging from
home-brew that can be mixed in flight, to unstable but widely available
nitroglycerin, to exotic blends -- the use of which could suggest
involvement of a nation-state.

"We've focused for the last 10 years on solid explosives and their
signatures," said William Martel, a professor of international security
studies at Tufts University. "Liquid poses a different problem. Liquids are
ubiquitous -- shaving cream, shampoo, bottles of water, juice, infant
formula."

According to Martel, the most common detection test -- in which a cloth or
tape is swiped over luggage and put through a sensor -- is specifically
designed to pick up residue from solid explosives.

"We didn't start looking aggressively for liquids until a few years ago,"
Martel said. Some, but not all, can be picked up by "sniffer" sensors using
a technique called neutron activation analysis.

Most experts say the main candidate is nitroglycerin. As far back as the
1930s, bank robbers learned to distill it from dynamite or make it directly,
so the technology is well known and within reach of the average terrorist.
It requires a detonator, making it somewhat complex and more readily
detectable as an in-flight bomb. The other potential problem: if poorly
formulated, it can explode without warning.

Nitroglycerin was the explosive of choice for Ramzi Yousef in Project
Bojinka, a terror plot foiled in 1995 in which 11 U.S.-bound flights were to
be bombed.

Vincent Cannistraro, former executive director of the CIA's counterterrorism
center, said he believes the latest plot involved a Yousef formula.

"It's nitroglycerin (plus other things), no question about it," Cannistraro
said. "We know it can't be detected by any security machines in use right
now, and so it scared the hell out of everyone."

Since the Bojinka plot, terrorists have focused on hand-placing tiny bombs
in critical structural parts of airplane cabins, rather than simply checking
bomb-laden luggage into cargo compartments, according to John Pike, head of
Globalsecurity.org, a Washington-based think tank. That's because a bomb big
enough to bring down a plane would be picked up rather easily by routine
baggage X-rays.

The newest form of liquid explosives are so-called "binary" formulas like
FIXOR, recently developed as part of the humanitarian campaign to clear land
mines in Third World countries. They're stable and undetectable until mixed,
and also require a detonator.

A home-brew candidate is triacetone triperoxide, also composed of two
liquids, used by Britain's July 7, 2005 subway bombers. It can be fabricated
from readily available chemicals. ANFO (ammonium nitrate and fuel oil, used
in the 1995 bombing of the Murrah Federal Building in Oklahoma) could also
be mixed in flight, but like nitroglycerin, it can be picked up by some
detection systems.

There are even liquid explosive blends that don't need a detonator, though
their exact composition isn't widely publicized.

 Do you have an opinion about this story?
Share it with other readers in our CAA Discussion Forums

http://www.californiaaviation.org/dcfp/dcboard.php


*****************************************