Deep in the hull of this 18-level aircraft carrier, in a place where few members of the crew are allowed to venture, Airman Brandy Powell builds bombs.

"It's a rush," said Powell, 18, of Golden, Calif., standing under the fluorescent lights of the bomb assembly room. Next to her were row after row of olive-green steel tubes stacked from floor to ceiling.

The 12-foot-long tubes -- each filled with explosives and bearing three rings of yellow paint around their pointed noses -- are the building blocks of her trade.

Powell joined the Navy eight months ago and is on her first tour of duty aboard the lead U.S. carrier in the Persian Gulf. She looks more likely to be found at a McDonald's after school than among rows of JDAMs, or Joint Direct Attack Munitions, "smart bombs" equipped with guidance fins and satellite targeting systems.

Powell is a "mag rat," one of about 100 people who work inside the 40 or so magazines, or bomb storage rooms, that are scattered across the ship. When airstrikes are flown, these people work like short-order cooks, piecing together specific bombs ordered for specific missions.

"It's a fast-paced job," she said. "I love building bombs."

Elsewhere in the magazine where Powell works were rows of GBU-16 and GBU-12 bombs. They were tied with chains to the floor to make sure they didn't move when the ship rolled. In another place, missiles lay clustered in green tubular cases.

All told, there were about 300 tons of explosives in the room.

Military leaders say if there is a war with Iraq, about 80 percent of the bombs dropped by U.S. forces will be smart ones -- conventional free-fall bombs that have been fitted with electronic guidance systems by people such as Powell. In the Persian Gulf War of 1991, only 10 percent of the bombs were smart bombs.

Some smart bombs home in on the reflections of laser beams that are aimed at the target; others use signals from Global Positioning System satellites to strike specific geographic coordinates. The guidance systems dramatically increase the number of hits and reduce civilian casualties from misses. Military strategists say the weapons are revolutionizing concepts of air power.

If Turkey prohibits the United States from flying combat missions from air bases in that country, naval officers expect that aircraft carriers such as the Lincoln will get extra duty in mounting the air assault.

At the entrance to the carrier's rear bomb assembly area, a metal plaque proclaims: "Weapons Assembly, Peace Through Power, When You Care Enough to Send the Very Best." Lighters and matches are prohibited in the assembly area, which has a high-power sprinkler system that can fill the area floor to ceiling with water in two minutes.

For now, the mag rats, wearing the red shirts of the ordnance division, spend most of their time maintaining and checking their supply of basic bombs, which weigh between 500 and 2,000 pounds. They are of various vintages -- some date from the Vietnam War.

The newest bomb guidance systems are the JDAMs, which have been part of the Lincoln's arsenal for about five years, according to Gunner Anson Michael Klaphake, 35.

If the Lincoln's F-14 Tomcats and F/A-18 Hornets get orders to hit Iraq, the rats will spring into action, working under closely calibrated rules to avoid accidents.

In one of two assembly rooms in the ship, they will hoist bomb bodies from pallets and lift them onto a conveyor belt in the middle of the room. Then they will attach laser guides, GPS devices, fuses and other components as ordered by the ship's tacticians for specific missions.

It takes about 10 crew members to build a bomb, and they will work at a pace that completes one every 10 to 12 minutes, said Lt. Paul Dosen, the weapons assembly officer.

As the bomb-making turns out a steady flow of ordnance, sailors will store completed bombs in the mess halls, on the flight deck, anywhere there's room. "We could also build them in the hangar bay if it gets that busy," Dosen, of Chicago, said.

The assembled bombs will be lifted by special elevators to the hangar or the flight deck to be attached to warplanes headed for Iraq.

Klaphake, of Melrose, Minn., has been building bombs in the Navy for almost 17 years. Early on, he used to think about what he was making and how it would be used. Now, he says, he never considers it. "It's my job," he said. "It's like you're in a factory and you're making a product. We just work on missiles and bombs."

Airman James Snider, left, and colleagues examined a cartload of GBU-35 bombs on the flight deck of the USS Abraham Lincoln last month.