home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
TIME: Almanac 1990
/
1990 Time Magazine Compact Almanac, The (1991)(Time).iso
/
time
/
010989
/
01098900.004
< prev
next >
Wrap
Text File
|
1990-09-17
|
2KB
|
44 lines
NATION, Page 27A Deceptive Killer
Few things so deadly have ever looked so innocent. They have
the appearance and consistency of soft taffy and can be molded,
stretched or cut into any shape. They burn so safely that American
G.I.s in Viet Nam used them as emergency cooking fuel. Yet plastic
explosives pack roughly twice the force of an equivalent amount of
dynamite. Many nations, including the U.S., produce them for
military purposes. But large amounts have made their way into the
hands of terrorist groups around the world, posing a fiendishly
difficult problem for airline security. Because the explosives can
be so easily formed into innocuous shapes, they can pass undetected
through security checks. The deadly plastic is also odorless and
cannot be sniffed out by trained dogs.
The Federal Aviation Administration has been working with two
U.S. companies to solve the problem. Starting next summer, the FAA
will receive five new devices developed by San Diego-based Science
Applications International Corp. for screening checked luggage. The
machine bombards luggage with neutrons that interact with the
nitrogen in explosives, touching off a characteristic pattern of
gamma rays. In tests conducted last summer at Los Angeles and San
Francisco airports, the devices spotted more than 95% of suitcases
containing test samples of explosive materials. But because they
employ dangerous radiation, the machines, which cost as much as $1
million each, cannot be used on passengers.
That is not a problem with the system designed by Thermedics
in Woburn, Mass. It uses jets of warm air to collect vapors given
off by either luggage or the clothing of passengers, who would be
required to step into a three-sided booth. The vapors are then
subjected to six different computerized chemical tests that
together take about 25 seconds. In a five-day trial run at Boston's
Logan Airport last October, the system, which would cost roughly
$250,000, nabbed 50 out of 50 test samples sent through.
Another technological approach would not prevent bombings, but
it could help identify those who commit them. Explosives can be
chemically "tagged" so that telltale traces can be used to
determine their origin after a blast. If producer nations could
agree on a tagging system for military explosives, it would
increase the chance that future terrorists might be tracked down
and brought to justice.