Here in the United States, federal air safety officials are growing increasingly concerned about the threat of terrorists acquiring hand-held missiles and shooting down airliners, something that has been tried at least twice in the past year.
Last November, a commercial Israeli airliner taking off near the Kenyan city of Mombasa was fired on by two anti-aircraft missiles, the kind that were used by fighters in Afghanistan to bring down Russian military aircraft during the decade-long Soviet occupation. The missiles missed their target. In May of last year, remnants of a spent anti-aircraft missile were found near an airstrip used by the U.S. military in Saudi Arabia, in another apparent attempt to bring down an airliner.
Both incidents sent a scare through the aviation industry and set off alarm within the U.S. government, so much so that it has now assembled a multi-agency task force to assess what experts consider to be an increasing risk to air safety in the wake of the September 11 terrorist attacks.
"It appears to be a concern that has increased greatly in recent days because of intelligence information," said Paul Hudson, executive director of the Aviation Consumer Action Project and a member of the government's aviation security advisory committee.
"There's evidence that a large shipment has been received by some terrorists of these missiles," he adds.
It's estimated that there are some 700,000 shoulder-fired, anti-aircraft missiles around the world. U.S. air safety officials fear some of them may have fallen into the hands of terrorists, including Afghan-based al-Qaida whose members could be planning to target commercial aircraft here in the United States.
"This is an existing threat that has been on the minds of people who worry about these things for some time," said Chet Lunner, a spokesman for the U.S. Transportation Department.
"In the wake of 9-11, the very first directive the FAA [Federal Aviation Administration] sent to airlines was reminding them that this threat still existed," he explained.
Although the threat is considered to be highest overseas, the U.S. government is now stepping up surveillance around American airports and training pilots on how to safely land a jet hit whose engines have been hit by missile fire. Many airports in the United States are located in urban areas and experts admit there's only so much that can be done to secure them from a weapon that is easily concealed and can be fired from a car window.
"There is no way that you can be sure that you've protected yourself. For example, you read that they're talking in terms of varying takeoff times. Well, that works in Israel when there are not that all that many takeoffs but if you take a really busy airport with a takeoff every minute, and a terrorist who doesn't care whether it's United or America or Delta or whoever, that's not relevant here," said Dave Bond, a senior editor at Aviation Week magazine.
So far, the risk has not prompted Homeland Security chief Tom Ridge to raise the nation's overall terrorist threat level. But officials from across the U.S. government will meet next week for another threat assessment.
"If a warning hasn't been issued, presumably it will be seriously discussed," said Paul Hudson, of the government's aviation security advisory committee.
There's also the question of whether the government or the airlines would pay for further security upgrades. One option would be to equip commercial airliners with decoy flares, similar to those used by military aircraft, that confuse heat-seeking missiles. But most airlines are already struggling to make a profit in the wake of the 2001 terrorist attacks and are likely to argue that it should be up to the government to pay for security enhancements.