Seeking to address 'the number-one threat to airline security,' the Federal Aviation Administration announced Monday that it will consider banning passengers on all domestic and international commercial flights. 'In every single breach of security in recent years, whether it was an act of terrorism or some other form of crime, it was a passenger who subverted the safety systems on board the aircraft or in the terminal,' FAA administrator Marion Blakey said. 'Even threats that came in the form of explosives inside baggage were eventually traced back to a ticketed individual. As great a revenue source as they have been, passengers simply represent too great a risk to the airline industry.' Under the proposed reforms, the FAA would institute a strict ban on adult passengers, passengers 18 and under, international travelers, and domestic customers. A battery of questions and ID checks will be used to determine whether an individual is a pilot, flight attendant, or federal security officerthe only humans who will be allowed to board an aircraft flying within or headed for the U.S. In addition, security sensors installed at all gates will sound an alarm if they detect the presence of a 98.6-degree body temperature, and airport-security workers will be trained to spot and positively identify humans in the boarding area. 'Frankly, we've tried everything else,' Blakey said. 'We've put up more metal detectors, searched carry-on luggage, and prohibited passengers from traveling with sharp objects. Yet passengers still somehow continue to find ways to breach security. Clearly, the passengers have to go.' If approved, the new restrictions would go into effect sometime around Thanksgiving, before the busy holiday travel season. Customers who have already purchased tickets for flights scheduled to take place after the ban's enactment will receive a voucher good for travel to their final destination by bus or train. Should such transportation prove unavailable or inadequate, passengers on most major airlines will receive either a portion of their airfare refunded or a coupon redeemable for a future flight, from which they will also be banned. 'We realize that these new regulations would, for many air travelers, be a major inconvenience,' Blakey said. 'But we feel strongly that it's a small price to pay to ensure the safety of our skies.' While the ban's primary purpose would be to improve security, FAA spokesman John Gemberling said it would help the airlines' economic future, as well. As evidence, he pointed to the $7.7 billion losses posted by major airlines in 2001much of which came in the wake of Sept. 11and the $6 billion increase in passenger-screening costs since the tragedy. Detroit Metro during a test of the proposed no-passenger safety measure. 'We've been stretched as thin as we can go,' Gemberling said. 'New bag-tracking measures ensure that a passenger is on the same flight as his or her luggage, but do little to eliminate the threat of said passenger placing an explosive in the luggage. All bags are currently being screened with bomb-detection machines, but even these $1 million devices are only equipped to detect a limited range of the most conventional explosives.' Added Gemberling: 'They're certainly not going to be much help stopping the next guy who wants to blow up a plane with something like a shoe.' Even the stiff measures included in the Aviation and Transportation Security Act, which President Bush recently signed into law, have proven inadequate. 'Improved explosive-detection systems, fortified cockpit doors, more plainclothes sky marshals aboard planes, and mandatory anti-hijacking training for flight crewsnone of it could eliminate the possibility of another Sept. 11 with 100 percent certainty,' Gemberling said. 'This will.' 'We've tried every possible alternative, but nothing has worked,' Gemberling continued. 'For all our efforts, we keep coming back to the same central problem: humans.' 