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Olympic fortress: Pentagon pulls out stops for safe Games

(CNN) -- Forget an ounce of prevention. Think tons. Vault-like. Whatever conjures images of impenetrability or extreme defense, the Pentagon has provided it in Salt Lake City, Utah, to make the Winter Olympics as safe as possible.

As the hour nears for the Opening Ceremony on Friday night -- an event President Bush will attend -- the local airport will halt all air traffic. The same will happen during the closing ceremony.

Starting Friday, airspace will be restricted in a 45-mile radius around Salt Lake City. All small aircraft will need special clearance to land there, and they will first have to travel to one of four nearby gateway airports and undergo security sweeps.

Monitoring airspace over the 110-by-35-mile swath of Utah where Olympic events will be held is a major part of the overall effort. The North American Aerospace Defense Command will conduct combat air patrols over the area, using F-16 fighters.

The Army has placed Black Hawk helicopters in key sites at the northern, eastern and western edges of the Olympic staging area.

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Security measures on the ground will be just as tight. The Winter Olympic Games will be the biggest international sporting event held since the September 11th terrorist attacks and will have the largest security presence ever for an Olympic games.

The Pentagon will spend more than $62 million on Olympic security, $45 million more than planned and reflecting post-September 11 funding requests.

There are more than 5,600 military personnel, both active duty and Army National Guard, to protect the Games. By contrast, there are 2,000 athletes and about 3,000 U.S. military personnel in Afghanistan.

A major post-September 11 change involved assigning an additional 3,000 National Guard soldiers from 25 states to perform a variety of duties, including manning screening devices and running mirrors under cars, said an Army official involved in the planning. Prior to September 11, volunteers and civilian law local enforcement were going to perform those tasks.

Underscoring some of the military aspects of the effort, the Army and Marine Corps are placing ground-based radars in the eastern foothills of the Wasatch Mountains to monitor aircraft flying below 10,000 feet or ground movement through the mountains.

One military official explained that while the FAA radars surrounding Salt Lake City airport on the west side of the mountain range are adequate, the eastern side of the mountain foothills proved to be a security "blind spot." Those radars and other airborne intelligence information will be transmitted to Hill Air Force Base in Utah.

Special security measures have also been implemented at Dugway Proving Grounds, about 80 miles southwest of Salt Lake City. Dugway is one of the Army's most closely guarded facilities for testing of chemical and biological defenses and is thought to house some live biological agents.

But security measures do not seem to have affected attendance. All hotels are full.