WASHINGTON (AP) _ The military is exploring ways to stop the around-the-clock anti-terrorism patrols that fighter jets have been flying over American cities since Sept. 11, defense officials said.
But four months after the devastating attacks on U.S. soil, any decision on ending the combat air patrols may come down to largely a political calculation of how safe Americans would feel without them, they said.
As a part of heightened homeland defense, the missions began after terrorist hijackers crashed jetliners into the World Trade Center and the Pentagon. They have flown constantly over New York and Washington since then.
Other patrols are flown randomly over other major metropolitan areas and key infrastructure, and jets are on alert at 30 bases across the country to scramble if called.
The military also has been authorized to order pilots to shoot down commercial aircraft if necessary.
Officials have been looking to cut back on the program for some time, knowing from the outset that the high-tempo use of manpower, equipment and money couldn't be kept up for long with the existing people and budget, one defense official said on condition of anonymity.
Now that four months have passed and aviation security has been improved somewhat, some wonder it if might be time to start rethinking the patrols, the official said.
The operation uses 11,000 people and 250 aircraft, another official said, also in return for anonymity. Those figures include maintenance crews, pilots for 100 F-15 and F-16 fighter jets, as well as crews for tankers needed for midair refueling and AWACS _ Airborne Warning and Control System _ planes to provide radar information.
At the Pentagon, Rear Adm. John Stufflebeem said Monday that pilots and crews of airborne warning aircraft may be operating so intensely that they are not getting their usual training for other missions.
``Maybe we're not getting the training that we need done now for our rotations overseas, so that's being looked at,'' he said. Stufflebeem is deputy director of operations for the Joint Chiefs of Staff.
The fighter pilots, mostly from Air National Guard units, go up for flights of two to six hours. The jets are refueled about every two hours, meaning some go through two midair refuelings on a single sortie.
From Sept. 11 to Dec. 10, the operation flew 13,000 missions. The cost was $324 million, Defense Department spokeswoman Susan Hansen said.
Air Force officials had no immediate comment Sunday.
The North American Aerospace Defense Command, which runs the operation, said periodic review of missions is standard procedure in the military.
``We continuously analyze our ongoing operations ... as a matter of prudent military planning,'' said Maj. Barry Venable, a spokesman for NORAD in Colorado Springs, Colo.
``We will continue to execute our role (in homeland defense) until the national leadership directs otherwise,'' he said.
NORAD says that through Dec. 10, its jets responded 207 times to problems such as unidentified aircraft, planes violating restricted air space and in-flight emergencies.
Not included in the figure is the case in which two jets escorted a Paris-to-Miami flight to Boston later last month after a passenger tried to ignite what authorities said was an explosive hidden in his shoes.
In 92 of the cases, jets on alert on the ground were scrambled to respond.
In the other 115 cases, NORAD diverted jets that already were in the air flying combat patrols.
Pentagon officials said privately that there is mounting stress on the people and planes that can affect readiness for other missions.
And while they believe the patrols are a deterrent to would-be attackers and give some Americans a greater sense of security, they also argue that scrambling planes against attacks is a measure of last resort. Security should be tightened on the ground before problems become airborne in the first place, they maintain.
One alternative to constant patrols would be to keep planes on ground alert, as was done before Sept. 11. They were on alert at a handful of places before it was ordered at 26 bases, then grew to the current 30.
In addition, airliner and airport security has been tightened in the last few months. Thousands of National Guard troops are on duty at the nation's airports. Screening of passengers and carryon baggage has been increased.
And under a new aviation security law, airlines are required starting next weekend to inspect all checked baggage for explosives.
Many officials believe it's still not enough.
Homeland Security Director Tom Ridge noted Sunday that the nation is still on high alert.
Though speaking about security in general and not specifically about the sky patrols, Ridge said in a CNN interview that much remains to be done. ``We still have to be very, very vigilant,'' he said.
The combat air patrols are the first of their kind to fly over the United States since the Cuban missile crisis in 1962.