Post-9/11 Air Patrols See False Alarms

July 21, 2002 -- Since Sept. 11, U.S. military fighter jets have responded to more than 400 domestic airline incidents requested by the FAA, and at times, the 24-hour combat air patrols were costing the U.S. Air Force up to $60 million a week.

But not all of the intermittent patrols were responding to real threats.

For example, last October the pilot of a Delta Airlines flight requested an escort after a passenger wrote a note disagreeing with the pilot's decision to change course due to bad weather.

Another example took place on Nov. 13, as two F-16's escorted a United Airlines flight into Denver because its pilots were slow to respond to a call. That was a false alarm as well.

Crying Wolf?

A spokesman for the nation's largest pilot's union said the problem is there are only vague standards for what should be considered a real threat. Experts say the uncertainty can lead to trouble.

"If you cry wolf, the system after a while is going to degrade and it's going to be less responsive, and so when you really need it to react it's not going to be there for you," said Jim Carafano a senior fellow at the Center for Strategic and Budgetary Assessments, a nonprofit public policy research institute that aims to promote innovative thinking about defense planning and investment strategies.

Though the fighter jets no longer patrol 24 hours a day, the intermittent combat air patrols still are costly. In addition, the military keeps dozens of fighters across the country on "strip alert" — meaning fully armed, fueled and ready to go. But, is all of this really necessary?

"Look, it is worth it," said Randy Larsen, of the Institute for Homeland Security. "Three thousand people were killed on Sept. 11. … This is a small price to pay."

Real Threats

And, there have been some real threats that were diverted by fighter jets.

For example, in December two F-15's shadowed an American Airlines flight diverted to Boston after a flight attendant noticed passenger Richard Reid trying to light a match to his shoe, which was later found to be laden with explosives.

In April, the Department of Defense announced it would be scaling back on the combat air patrols. Still, officials said the jets continue to patrol the skies over New York City and Washington, D.C.

However, they believe that as flight crew training improves, cockpit doors are reinforced, and ground security is upgraded, fewer fighter jets will be activated.

ABCNEWS' Martha Raddatz contributed to this report.