WASHINGTON (AP) _ The Air Force has successfully tested a bomb designed to enable its fleet of B-2 Stealth bombers to attack targets anywhere in the world, day or night, in all weather conditions.

``The new Northrop Grumman-designed weapons system (provides) our B-2s with unprecedented near-precision, adverse-weather conventional weapons capability,'' Brig. Gen. Thomas B. Goslin said Thursday.

The weapon, code-named GATS/GAM, comprises a standard 2,000-pound bomb equipped in the tail kit with a global positioning system receiver, a satellite-based locating device. The unit is linked electronically with the B-2's sophisticated radar, which pinpoints ground targets and feeds the data to the bomb.

The combination allows the weapon to accurately hit targets such as bridges, command bunkers, and missiles in zero visibility, the Air Force says. Infrared, electro-optical or laser-guided bombs of the type used in the 1991 Persian Gulf War are rendered ineffective by cloud, rain, snow or smoke, which their sensors and laser beams cannot penetrate but to which radars are impervious.

Post-Gulf War assessments showed that ``smart'' weapons were far less effective against Iraqi targets than originally thought.

Goslin said the GATS/GAM will do the same job as a cruise missile such as those fired in recent months against Iraqi targets. At $192,000 each, however, the weapon is 10 times cheaper than a single cruise missile.

An additional advantage of GATS/GAM is that it allows B-2 bombers to attack from altitudes of over 40,000 feet, where the danger posed by surface anti-aircraft missiles is reduced significantly. During the Gulf War, mid- to high-altitude bombing tactics used to avoid having planes shot down resulted in inaccurate strikes, even with precision weapons.

``The precision, accuracy of the delivery, combined with the B-2's great range and payload and its ability to strike in adverse weather, will add a significant dimension to the Air Force's ability to project U.S. power anywhere in the world,'' said Goslin, commander of the 509th Bomb Wing at Whiteman Air Force Base, Mo.

The 509th is the only unit to operate the radar-evading strategic bomber.

Three of its planes were used in the first live GATS/GAM drops Oct. 8 at the Nellis Air Force Base range in Nevada, Goslin told reporters. Sixteen bombs destroyed the same number of individual targets, without a miss.

At $1 billion apiece, the B-2 is the most expensive aircraft ever built. With a crew of two, it is difficult to detect in flight because it has no vertical tail surfaces and the plane's skin absorbs rather than reflects radar signals.