Why `Smart' Bombs Miss -- Clouds Affect Laser's Ability To Guide, Officials Say

WASHINGTON - Only about 60 percent of the U.S. laser-guided bombs dropped in Operation Desert Storm have hit their targets, and the 40 percent that miss have been off by as much as thousands of feet, according to past and present government officials who are familiar with U.S. intelligence reports.

Before the war, Pentagon officials estimated it would take 10 days to complete the air campaign, according to members of Congress who were briefed. By then, they said, the U.S. bombing would have destroyed Iraq's air force, air-defense sites, command-control systems, Scud missile launchers and its nuclear-, chemical- and biological-weapons facilities.

However, after nearly two weeks of warfare, Pentagon spokesmen have reported that while all these targets have been damaged, none except the nuclear-weapons factories has been destroyed.

The Desert Storm results are consistent with the most recent tests of laser-guided bombs, known as the Paveway III program. Of 39 bombs dropped in those tests, only 19 hit their targets, according to a retired Air Force officer familiar with the tests.

The officer, who requested anonymity, said successful bombs landed within 10 feet of their targets, but the misses landed as far away as five miles.

There are four types of laser-guided bombs in the U.S. arsenal, with payloads ranging from 500 to 2,000 pounds, but they all work on the same principle. A laser beam is aimed at the target, and the bomb homes in on the beam, following it all the way to the target, where it explodes on impact. However, several officials say the beam does not shine through smoke, dust, clouds or rain. Instead, it reflects and refracts these particles, distorting the path of the bomb.

John Lehman, the secretary of the Navy under President Reagan, told CNN television Saturday that laser-guided bombs ``do go ballistic if . . . suddenly a cloud comes between the plane and the target . . . and they'll go wide.''

Lehman, who remains enthusiastic about high-tech weapons, said friends in the Pentagon tell him about 60 percent of laser-guided bombs have hit their targets in Iraq, which he said was ``consistent with the test performances.''

An administration official familiar with preliminary assessments of the Gulf war confirmed this finding yesterday.

In Vietnam, U.S. planes dropped more than 250 laser-guided bombs and hit fewer than 40 percent of the targets, according to a former Pentagon official who studied the bomb-damage assessments.

In the 1983 war in Grenada and the 1986 bombing of Libya, the performance of the bombs was even worse, this former official says. The unclassified version of a report by the U.S. General Accounting Office said the laser-guided bombs had ``significant problems'' in those two wars, and that old-fashioned iron bombs - which simply fall out of bomb-bays - destroyed a higher percentage of targets.

But older-style bombs have problems of their own: ``Dumb'' bombs tend to sink far into desert sand before exploding, minimizing their impact.

``We've seen bombs that go 40 meters (about 130 feet) into sand and never explode,'' said a Kuwaiti air force pilot, 1st Lt. Talal Raqueeb, after a bombing run over Iraqi tank and troop concentrations in Kuwait.

Lehman said that, as a result of the misses in Iraq, ``there probably have been at least 2,000 or 3,000 civilian casualties.''

The Pentagon officially has no estimate of Iraqi civilian casualties. Iraqi President Saddam Hussein has not released high estimates of casualties either, leading many officials to suspect the figures are low.

-- Knight-Ridder Newspapers contributed to this report.