Cheney, Powell Given Upbeat War Appraisal : Persian Gulf: They meet with battlefield commanders to get advice on waging a ground war. U.S. officials report wide-scale destruction and desertions among Iraqis.

RIYADH, Saudi Arabia —  President Bush’s top defense advisers descended into a war room Saturday to hear straight talk from battlefield commanders about the Persian Gulf War. The commanders offered facts, analysis and hunches about whether Bush should order a ground assault into Kuwait--and what it might cost.

Secretary of Defense Dick Cheney and Gen. Colin L. Powell, chairman of the Joint Chiefs of Staff, met for 8 1/2 hours--longer than expected--in the map-lined war room at the Saudi Defense Ministry with Gen. H. Norman Schwarzkopf, commander of U.S. forces in the Gulf, and others at the top of the Central Command.

The session was wrapped in secrecy, but if public statements from military leaders in the command were any guide, Cheney and Powell heard that the 24-day war against Iraq has done a mighty job of “softening” the enemy, destroying a fifth or more of its artillery and armor and provoking desertions on what may be a significant scale. Marine Brig. Gen. Richard I. Neal succinctly described the military commanders’ mood at the critical briefings as “upbeat.”

Neal, deputy operations director for the Central Command, gave this assessment of the war thus far: Nearly 20% of Iraq’s tanks in the Kuwaiti theater have been destroyed, along with more than 20% of its artillery and about 15% of its armored personnel carriers.

Cheney and Powell, who leave Saudi Arabia today, will bring what they heard to the White House on Monday and offer recommendations to President Bush, who has said he will decide about whether and when to order a ground assault into Kuwait to remove the occupying army of Iraqi President Saddam Hussein.

In other developments:

* U.S. officials in Washington disclosed that American warplanes for the first time this week began dropping a huge conventional bomb on Iraqi forces. Known as the BLU-82, the bomb creates a massive shock wave and levels everything within hundreds of yards.

* U.S. Navy officials confirmed that a missile narrowly missed the Nicholas, a frigate running patrols in the northern Persian Gulf. The officials said it was unclear what kind of weapon was fired or whether it was of allied or enemy origin. Shrapnel struck the superstructure of the frigate but caused no injuries or serious damage.

* British Prime Minister John Major told an audience of young Conservative Party members in London that Hussein “cannot win.” He also said it would be “most agreeable” if the Iraqi people overthrew Hussein before a ground war began. But in Baghdad, a newspaper printed by the Iraqi Defense Ministry said victory by Hussein’s forces is certain.

In a briefing for reporters, Gen. Neal gave this breakdown of damage to Hussein’s army: Of 4,000 Iraqi tanks in the Kuwaiti theater of operations, 750 have been destroyed. Of 3,200 pieces of artillery, Iraq has lost about 650. Of 4,000 armored personnel carriers, about 600 have been destroyed.

“These are destroyed,” Neal repeated for emphasis. “This is a critical point. A lot of things have been damaged, but unless we see a tank belly up, its treads off, turret askew, we will not count it as a kill.”

Destruction of artillery is considered critical because such weapons are a specialty of the Iraqi army, and some military experts have said that Iraq’s guns are superior in range to U.S. artillery. And finally, the destroyed armored personnel carriers weaken the capability of the Iraqi army to engage in mobile battles.

In addition, Neal said, 35 key highway and seven important railroad bridges have been attacked in a stepped-up effort to cut supply routes from Baghdad south to the Kuwaiti theater of operations.

Deserters

But perhaps the most tantalizing information to emerge was U.S. confirmation of reports, previously attributed to Saudi sources, that Iraqi soldiers--hungry, filthy, tormented by bombing and sick of war--are deserting their posts and heading north out of Kuwait and toward home in Iraq.

“A lot of people are deserting up north,” Neal said. “They don’t know where they are. They’re being told they are three or four days from Saudi Arabia. . . . They’re afraid of Westerners. They have been told Westerners will torture and brutalize them.”

He declined to estimate how many were heading north.

But he said it was “probably true” that they exceeded the 1,000 or so who have surrendered to allied coalition forces to the south.

“To a man, they talk about the endless bombing,” said Neal.

The fate awaiting deserters who go north was unknown, but Saudi commanders have said they have been told by some Iraqi prisoners of war that Iraq maintains “execution battalions” behind the front lines to discourage desertions.

Col. Ahmed Robayan, a spokesman for the Saudi command, said the latest group of 21 deserters who headed south into allied hands included an Iraqi lieutenant colonel--the highest-ranking officer to defect thus far. He said that the group also included three lieutenants.

In addition, someone, possibly a Kuwaiti resistance fighter, sent a message to the allies south of the Saudi-Kuwaiti border.

An unmanned, remotely guided plane patrolling the coast of Kuwait beamed back a video image of an oil tank farm--and near it, something that looked like a set of fortifications. As the camera zoomed in for a closer look, it became clear that the image was actually a giant set of letters etched into the sand.

Each letter was at least three stories tall. They formed a message clearly aimed at allied pilots winging overhead.

The message said: “FREE KUWAIT.”

The Air War

U.S., British, French and Saudi fliers pressed the allied air war with another 24 hours of bombing. They flew more than 2,400 missions--for a total of 57,000 so far in the war, including both combat and support sorties.

In the air, F-15 pilots reported having seen the Scud missile that was launched into Israel before dawn Saturday. But the early morning cloud cover was so heavy, Gen. Neal said, that the missile surprised them.

“It came up through, and they were flying overhead,” Neal said. “When they went down to try and find the launch site, because of the weather they were prohibited from making actual visual sighting of the launch site.”

Nonetheless, the pilots killed a second missile launcher before it could fire.

The missile that was launched fell in Tel Aviv. It caused considerable damage and injured about 20 people, none seriously.

Cheney and Powell

For all the terror and destruction that rained down on this day, however, much of the eager attention was directed at the meeting among Defense Secretary Cheney, Gen. Powell and their top allied commanders.

Cheney and Powell were described by Gen. Neal as mostly “in the listening mode.”

He said they stayed in the allied war room longer than scheduled, unexpectedly scrubbing a morale-boosting visit with rank-and-file troops at a Patriot anti-missile battery nearby. Instead, they gathered facts, analysis and soldierly hunches to take back to President Bush to advise him about a possible ground advance.

Each of the three military services and the Marine Corps were represented by senior generals. Cheney also asked to hear from Army division and brigade commanders who would be the ones to execute any presidential order to engage Iraq’s half-million-man army inside occupied Kuwait.

“Very, very impressive,” said a senior military adviser of the high-tech, straight-talk briefing.

When he was asked about the mood of the military commanders, Neal said, “It was upbeat.”

This was the first chance for Cheney to meet with commanders and assess the war at a working level. Military and defense experts said the session allowed both Cheney and Powell to draw out the commanders’ professional hunches.

These, the experts said, were likely to go beyond the extremely conservative battle assessments that the Central Command has made its trademark.

“I don’t think you’re going to see a circle on a calendar” as a result of the war room meeting, said a senior Pentagon official in the defense secretary’s traveling party. “There are a bunch of things we need to have in our basket before we can proceed to the gate. And we have a lot more to do yet.”

The Bomb

The big bomb described in Washington, nicknamed the “Big Blue 82,” is a 12,600-pound explosive.

A senior Pentagon official said that several were dropped somewhere in the Kuwaiti theater last week. “It’s a big noisemaker,” the official said, adding that it is being used both for its explosive power and for its effect on enemy morale.

The largest weapon used previously in this war had been a 2,000-pound bomb.

Big Blue was last employed in Vietnam, where it was used to clear helicopter landing zones. It is detonated only 38 inches above the ground, where it sends intense shock waves for hundreds of yards. It flattens trees and buildings and kills everything in its path, according to published descriptions of its effects.

The unguided bomb was dropped from C-130 transport planes in Vietnam.

Officials would not specify which planes are dropping it in the Gulf war or against what targets it is being used.

The Nicholas

The narrow miss at the Nicholas came when an unidentified missile crossed the bow of the frigate and detonated about 20 yards away.

Lt. Mark Walker, a Navy public affairs officer, told combat pool reporters that crew members aboard the ship reported seeing a bright flash, and lookouts felt the heat of the blast.

Cmdr. Dennis Morral, the ship’s commanding officer, said he initially believed that the vessel had drawn too close to the nearby battleship Wisconsin as it fired its huge guns and that part of a spent shell might have fallen nearby.

Fragments from the missile have been sent ashore for analysis.

It was believed the weapon might have been a stray surface-to-air missile or perhaps an artillery-type unguided rocket or an anti-ship missile.

Where it came from remained a mystery.

Britain’s Leader

In London, Prime Minister Major started his speech as five B-52s, laden with 500-pound bombs, took off through snow flurries on their first mission from Fairford in western England--apparently heading for a bombing mission over the Gulf. During the morning, observers saw U.S. crew members sweeping snow off the wings of the eight-engine Stratofortresses before loading the bombs on board.

Major said that while the timing of an allied ground attack in the Gulf is uncertain, results are not.

“He (Hussein) faces defeat,” Major said.

In Baghdad, however, Al Qadisiya, the Iraqi Defense Ministry newspaper, said that “Iraq will not conceal the fact that the ground battle would be severe and painful. But the results will be more painful (for the Americans and their allies) than they imagine.”

The paper was quoted on Baghdad Radio as renewing calls for terrorism.

It said terrorists should double “their heroic operations and deal painful blows to the interests of the aggressors worldwide.”

A military communique said there were 250 air raids in Baghdad during the night and morning.

The allies, it said, suffered “significant losses.”

Times staff writers Kim Murphy in Dhahran, Saudi Arabia, Kenneth Freed in Nicosia, Cyprus, William Tuohy in London and John M. Broder in Washington contributed to this article.