Tactics Switch May Have Boosted Navy’s Invasion Toll : Panama: A last-minute change increased the exposure of commandos sent to sabotage Noriega’s plane. Four died in the ensuing exchange with the dictator’s loyalists.

Pentagon officials assessing last month’s Panama invasion believe that an 11th-hour change of orders could have contributed to the high casualty toll suffered by a group of Navy SEALs in an attack on Punta Paitilla airport, The Times has learned.

Only hours before the Panama invasion’s “H-hour” on Dec. 20, three commando platoons--about 48 men--were moving secretly toward the airport to destroy Panamanian leader Manuel A. Noriega’s specially equipped airplane to prevent him from using it to escape.

But at the last minute, the units of the Navy’s sea-air-land commando force received new instructions: They were only to disable the plane by wrecking the undercarriage so the plane could not take off, an assignment calling for near-surgical precision.

That decision, apparently made by Gen. Maxwell R. Thurman, commander of the Panama-based Southern Command, reflected a desire to minimize damage to the populous residential area surrounding the airport, officials said.

But it required the SEALs to get much closer to the aircraft than the plan they had rehearsed. It also required them to move more fully into the open, where they were exposed to a small but heavily armed Panamanian force in the fierce fire-fight that ensued.

Four SEALs were killed in the operation, and three were so badly wounded that their return to the Navy’s elite commando service is considered improbable.

The SEALs’ tactical change apparently was compounded by flawed U.S. intelligence that underestimated the type of protective force that the Panamanians would have in place at the airport, officials said.

The revised orders and faulty intelligence are prompting some criticism among military analysts, who contend that either a larger force should have been used or the target should have been subdued first with artillery.

“It did expose them to more risk,” said one defense official with a detailed knowledge of the operation.

Had they known earlier about the larger threat and the new assignment, the official said, “they would have fought a different battle. They would have stood off and softened the place up (with mortar fire). They’re not in the John Wayne business.”

“Someone made a bad decision,” another official said. “The SEALs were doing something they weren’t trained to do. The mission they did is normally a (Army) Ranger mission.”

The unforeseen restriction on the use of heavy firepower and the unexpected ferocity of the small band of trained Noriega forces have caused soul-searching on the part of the SEALs’ leadership and in the Pentagon office responsible for the commandos’ training and equipment.

“It was a mistake,” said one knowledgeable source. “It looks like a few guys bought it who didn’t have to. It’s fair to say that people are taking a look at it.”

The Pentagon review, he said, is intended to determine if such last-minute changes can be avoided in future operations.

Complicating the SEALs’ task, officials said, was the critical intelligence failure. In briefings before the operation, the SEALs were told that the only security at Paitilla airport would be untrained and lightly armed civilian security police.

Described by one official as “rent-a-cops,” the security police were considered more likely to run than to stand and fight.

Instead, a small band of Gen. Noriega’s elite special operations forces awaited the SEALs, armed with automatic weapons--including a Browning automatic rifle, according to one on-scene report.

The Panamanians, tipped off to the arrival of the invading U.S. forces by waves of arriving transport planes, had taken up positions in a spot with a panoramic view of the airfield--and an unobstructed line of fire on the SEALs advancing toward Noriega’s aircraft.

While no Panamanian leader made a move toward the aircraft, intelligence analysts operating offshore warned the SEALs that armored personnel carriers filled with Panamanian soldiers were approaching Paitilla, spreading fears that the troops at the airport were being reinforced. But officials said that contrary to earlier published reports, the armored personnel carriers bypassed Paitilla and continued onward to defend Noriega’s military headquarters.

As a platoon of SEALs advanced on Noriega’s aircraft, they saw a Panamanian gunman and opened fire. Besides the U.S. casualties, a Panamanian intelligence officer who later surrendered to U.S. forces revealed that three Panamanian commandos had perished in the attack and eight Panamanians were taken away in ambulances.

Ironically, the Americans came under such intense fire that they were forced to abandon hopes of disabling the airplane with minimal firepower. In the end, the SEALs used “all they had,” according to one source, destroying Noriega’s plane and at least two other aircraft, as well as Paitilla’s hangar.

The wounded SEALs waited in some cases for hours for medical evacuation, a problem that officials attributed partly to communications lapses.

These problems have prompted Navy officials, in “lessons-learned” reports submitted to the Pentagon, to stress the SEALs’ need for communications channels and specially equipped helicopters of their own. The requested choppers, a version of the Navy’s LAMPS 3 anti-submarine helicopter, are being built and delivered to the SEALs as early as this week.

The U.S. casualties made the Paitilla operation one of the bloodiest exchanges of the entire Panama invasion, which left 23 Americans and more than 500 Panamanian soldiers and civilians dead. Officials said the Navy will recommend that several of the commandos who participated in the Paitilla attack receive awards for their valor.

Several SEALs dashed onto the Tarmac to drag the wounded to safety as Noriega’s gunmen raked the airfield with fire.

One of those killed, Lt. (j.g.) John P. Connors, was maneuvering with his squad to reinforce a group of SEALs under fire, said one knowledgeable source. To join the SEALs in Panama, Connors had left a hospital where he was being treated for a skin disease contracted while training in Brazil.

Elsewhere in Panama, Navy SEALs successfully sank escape boats and secured critical facilities without serious casualties. In those areas, the SEALs conducted more traditional missions: Moving in small teams of about 16 men, they conducted sabotage missions and other operations, usually with enough stealth to avoid engagements with Panamanian soldiers.

The SEALs’ Paitilla mission was a somewhat unconventional assignment for them, according to knowledgeable officials. Pentagon sources said that any further bolstering of the force would have removed the elite service even further from the missions it was intended and trained to conduct.

Said one knowledgeable source, “SEALs don’t do missions where you have to ‘soften up’ the target in advance” with artillery.

“This was a large force for the SEALs,” said another defense official. “But if they’d gone in with that guidance from the beginning and known what was there, they wouldn’t have done it this way and maybe taken fewer casualties.”