President Carter's intelligence chief says a new inquiry should be made into the failed Iranian hostage rescue mission attempted two years ago today.

Retired Navy Adm. Stansfield Turner, director of the Central Intelligence Agency during the Carter presidency, called the raid a "searing national experience" that has not been completely plumbed for the lessons it holds for the nation.

Gen. David C. Jones, chairman of the Joint Chiefs of Staff and the principal architect of the rescue mission, which ended in flaming disaster on the Iranian desert, said yesterday that such an investigation would serve no useful purpose because there is little about the raid that has not already been explored.

This article was reported and written by staff writers Scott Armstrong, George C. Wilson and Bob Woodward.

This difference of opinion over whether a new review is in order comes at a time when other senior officials involved with the April 25, 1980, midnight attempt to extract 53 hostages from Tehran are confirming that the operation was much bigger and bolder than the public has been told to date.

A series of interviews conducted by The Washington Post disclosed a sharp difference in perspective among top military leaders, some lower level planners and other Carter administration officials who knew what American troopers and warplanes were prepared to do. Contingency plans included rushing in a backup force of 90 more commandos if the initial assault force of 100 men under Col. Charles A. (Chargin' Charlie) Beckwith got trapped in Tehran or the nearby airport destined to be the takeoff point for their long-distance escape from Iran.

Military leaders insisted they were counting heavily on speed, surprise and stealth and believed it might even be possible to pull off the rescue without firing a shot at anybody. Carter and his top aides were willing to accept limited casualties and some officials believed there would inevitably be deaths, perhaps hundreds if the firepower available to Beckwith was called in.

Noting such conflicting viewpoints and arguing that the raid has too many policy implications to ignore any longer, Turner said:

"It is now time to appoint a small group to examine how the operation was planned and executed. The purpose would not be to look backward and cast blame but to look forward and learn the lessons that surely lie buried in" the complicated mission.

"Some of the questions that should be addressed would be: What does the experience tell us about national decision making? About our military capabilities, organization and motivation? About the problems of totally secret military operations."

Contended Jones in a separate interview:

"We're not going to have another situation just like the Iranian situation. They never repeat themselves. Let's look at the fundamental problems like organization rather than taking an isolated case. We don't need to go back and look at things that happened two years ago. Let's get on with solving those fundamental problems," with reorganizing the Joint Chiefs of Staff, a priority high on Jones' list.

Reforms made since the 1980 raid, particularly integrating military forces of the various services into a ready-to-go anti-terrorist outfit, Jones said, make the United States "much better off today" to pull off a rescue successfully. He noted that a panel of officers under retired Adm. James L. Holloway III has already delved into the Iranian rescue mission and issued a critical report.

Turner and some other former senior administration officials and military planners are known to think that the Holloway investigation was too limited and amounted to the military investigating itself.

That Carter's chief intelligence executive, who was in on the top secret planning for the raid, is willing to urge a new inquiry strongly suggests there is still, on the second anniversary of the raid, a lot more that could be told.

Interviews with Carter administration officials, military leaders and people who went on the raid buttressed that viewpoint in bringing these fresh disclosures, some of them contradictory, about the most daring rescue ever attempted by the American military:

* Getting into the embassy undetected depended in part on information secured by the CIA from a handful of infiltrated agents and bribed guards among the student militants, including some who were scheduled to be on duty as guards the night of the raid.

Some Carter administration officials said the plan called for all the guards to be killed, while military leaders insisted the "Delta" force under Beckwith was equipped with special hand and leg cuffs that could be snapped on the guards in an instant--and would have been if the troopers had sneaked into the embassy as anticipated. Military leaders doubted the CIA or anyone else had managed to co-opt the guards, but acknowledged they were not responsible for that part of the mission.

* Although Carter firmly ordered that every effort be made to keep the loss of Iranian life to a minimum, he gave the chairman of the Joint Chiefs virtually a free hand once the mission got under way.

One top Carter aide who participated in the planning meetings recalled that the president "said the military could use what was necessary to get the Delta team Beckwith's men in and then get the Delta team and the hostages out." Jones said everybody understood before launch that the military was to go to great lengths to avoid bloodshed.

* Carter increased the air support himself in what one aide called "military overkill."

While acknowledging three C130 gunships and dozens of fighters and fighter-bombers were committed to provide cover directly over Tehran, along the exit routes and over Iranian air force fields, military leaders said they would not have strafed or bombed unless things went wrong on the ground. No more than four U.S. fighter planes would have been over Iran at any one time, top military leaders said.

(As it turned out, Carter ordered the rescue mission aborted during the first phase because of mechanical failures in two of the eight helicopters and the return of a third to the Nimitz aircraft carrier after running into an unpredicted dust storm on the way to the first stop, called Desert One, in the Iranian back country near Tabas, 270 miles from Tehran. Eight American servicemen were killed in a refueling accident at Desert One after the mission had been called off.)

* The Air Force had three C130 gunships deployed, code-named Hammer, one to orbit over the embassy compound, the second to cover Iranian warplanes at the Tehran airport and a third to protect the raiders as they left Iran. The gunships were authorized to lay down a curtain of machine-gun fire to repel any crowd that might try to block the way of the rescue team and hostages, who were to rush across the street to a soccer stadium to board helicopters.

* The Pentagon deployed to Egypt a 90-man backup force code-named Python. It was to rush in to help Beckwith's team if an emergency developed. An 83-man force of Army Rangers also was deployed to seize the escape airfield outside of Tehran called Manzariyeh.

* Soon after taking over the CIA, the new director, William J. Casey, forwarded a highly classified CIA report to President Reagan that seriously questioned whether the covert and overt support of the rescue team was adequate.

Several former Carter aides vehemently denied that there was any such inadequacy, while military officials said they were often furious that the CIA could not give them better information to help ensure success of the raid. Turner is said to believe that CIA infiltrations and penetrations in Tehran were good, ranging from "adequate to superlative."

* One reason for the expected success of the latter stages of the mission, which were planned in detail but never executed, was that the Delta team helicopters would be disguised with Iranian military insignia.

Iranian agents accompanying the Delta team would be dressed in Iranian uniforms as well. This was expected to generate mass confusion near the embassy and create the impression that the American raiders were an Iranian military outfit responding to a rescue or a coup attempt.

* Iranian air defenses guarding U.S. entrance routes had been sharply reduced on the planned rescue night because a high-ranking Iranian defense official recruited by the CIA had ordered the mobile ground-to-air missile and radar facilities relocated to the northwestern border of Iran or sent out on maneuvers. Several U.S. military leaders said they had no knowledge of this arrangement.

* Before he resigned because of his objections to the mission, Secretary of State Cyrus R. Vance told Carter that the overall hostage crisis was not causing extensive damage to national security.

The planned rescue mission might, however, harm national security, he warned. Vance said the Iranians might well round up another bunch of Americans, such as oil company employes and journalists, putting the U.S. government back in the same bind.

* Counting air crews and backup forces of troopers, more than 400 Americans and others supporting the mission could have been involved on the ground in Iran at the moment when the raiding party was to free the hostages.

* Carter withheld final approval for the mission until the weekend of April 19-20 and never seriously considered a punitive or retaliatory strike against Iran, though his national security adviser Zbigniew Brzezinski repeatedly urged such action. Brzezinski also suggested that in order to emphasize the mission's importance, the president send Brzezinski along with Beckwith's team. Carter quickly dismissed the idea.

* Consideration was given to knocking out the main radio transmitter in Tehran during the raid in order to prevent a warning broadcast that might trigger retaliation against the 200 U.S. civilians and journalists in Iran. Carter finally rejected the option.

The rescue mission is likely to grow increasingly controversial as new details and disputes emerge from the books now being written by at least six Carter administration officials.

The U.S. Embassy in Tehran was overrun on Nov. 4, 1979. Concerned that the militants might kill the hostages, a small cadre of Pentagon planners working in the Office of the Joint Chiefs of Staff began outlining rescue contingencies that afternoon.

Initially, military and civilian officials doubted a successful, small-scale rescue of the hostages could be done.

W. Graham Claytor, deputy secretary of defense under Carter, recalled: "The entire problem was that the hostages were in Tehran, which is way inland. If it had been on or near the coast, we could have got them out . . . . That was a big, unprecedented problem."

There was no U.S. base nearby, and, as Claytor says, "We had no plan, no training, no intelligence."

The planners concentrated their approach on the Egyptians, who had several airfields near the Aswan dam that looked promising and were within 1,400 miles of the Iranian coast. By December, Egyptian President Anwar Sadat had agreed to provide a staging base at Qena, an airfield north of the dam. U.S. radar surveillance planes and airborne command posts moved in almost immediately.

During the late winter, a negotiating back channel between White House chief of staff Hamilton Jordan and Iranian officials began to look promising to Carter. When the negotiations ran into trouble, the White House began to consider asking U.S. allies to join in an economic boycott of Iran. But these new strategies would take months to implement and months more to work. The level of White House frustration was building daily.

"We got into a posture of threatening reprisals," one senior official said. "We got in a box. It was negotiate, negotiate, then threaten, threaten, and what could we do next? The rescue mission was the only military option that could lead to the release of the hostages."

On April 16, the Pentagon planning group briefed the president on a mission it thought could succeed.

After flying from Qena airbase in Egypt and stopping at Masirah Island, Oman, the first day of the mission would open at 6:55 p.m. when an MC130 transport plane with a radar-guidance system that allowed it to fly undetected would penetrate the Iranian coast.

The entry point near Chah Bahr, where U.S. construction crews and military planners had been building a large naval base when the shah, Mohammad Reza Pahlavi, fell, was chosen because it was largely deserted. The Iranian coastal radar system left a substantial gap--one that was supposed to have been filled, at least sporadically, by the Airborne Warning and Control System (AWACS) the shah had ordered but never received.

Five more planes would follow north and then northwest through the mountains. All six would then head for an unpaved but hard landing strip 500 miles inland in the middle of the Iranian desert. The spot was near a road that intelligence experts expected to be lightly traveled.

The first plane would arrive 34 minutes before the others so it could swoop low to check the unmarked spot and land with a specially trained company of Rangers who would secure the area and set out infrared markers on the edge of the runway.

Within the next hour, Beckwith's Delta team would arrive in two more MC130s, accompanied by three C130s carrying fuel. Behind them would come the eight slower helicopters flying from the aircraft carrier USS Nimitz.

After an hour to refuel the helicopters, the Beckwith force of 100 men, plus the dozen or so Iranian agents, would board them and fly for 2 hours, 13 minutes, straight toward Tehran.

Fifty miles southeast of the city, the choppers would deposit the Delta team out of sight of trains moving along nearby tracks; then fly three miles away to a bulldozed hideout in the mountains, code-named Figbar. Guards were deployed around the hiding spots and would have temporarily detained any intruders.

Eight trucks would pick up Beckwith's team before dawn at an old caravan stop near Figbar and drive them on a main highway and then on a back road to a remote warehouse (code-named Charley) provided by a local merchant. The trucks would be dispatched at intervals resembling normal commercial pick ups and deliveries.

During the next day, covert teams previously filtered into Tehran under false passports issued by other countries, would brief the Delta team. At the end of the day, the Delta team would break up into smaller units and, masked by commuter traffic, drive the last 15 miles to hideouts in the city, where they would remain until late that night.

The most recent intelligence report from informants among the militants indicated that there were likely to be as few as 15 guards in the entire embassy compound. Only three or four would be stationed outside. One habitually leaned his rifle against the building and slouched against the wall. The stories about extensive booby traps and mines appeared to be false.

"We had an intelligence breakthrough at the last minute," said one senior official. "We had predicted where the hostages were . . . and we learned later we were right."

Drum Beat, the code word for the moment when Beckwith's assault team was to hit the embassy wall, was scheduled for 10 minutes after midnight. One group would cut phone and electrical lines. One official said perhaps only one guard on the outside of the wall would have to be killed to get inside without detection.

Based on intelligence and a study of architectural drawings of the two buildings housing hostages, the team knew where the guards and hostages were likely to be. The team was confident it could overcome the guards silently, before they could harm the hostages.

The president "was not naive that we were going to tie the hands of the guards," one senior Carter aide said last week. "You weren't going to spend time tying the hands of people and jeopardize the mission." They would all have to be killed, even those on duty who had helped.

When the hostages were assembled, the hostages and raiders would move to the northeast corner of the compound. Using the code word Dynamo, Beckwith would call in the helicopters, the group would move briskly across the broad intersection of Roosevelt Street to a nearby soccer stadium. Their movements would be covered by a prepositioned combat control team on the corners of the stadium's walls.

Two helicopters would arrive at the stadium moments later. Two more that had been loitering above a construction site five miles north would arrive seven minutes after that, and another two (if they made it to Tehran) a few minutes later. In all, the plan alloted 30 minutes to load the helicopters.

In the event that crowds gathered, the Iranians accompanying the Delta team, but dressed as if they were Iranian revolutionary guards, were prepared to shout in Persian either that they were trying to prevent a rescue attempt by the Americans or a coup attempt. The planners hoped that in the impending confusion the crowd would disperse.

If the crowd got out of control or if snipers began firing, one of three AC130s (code-named Hammer) circling overhead would spray the streets with bullets. Armed with a rapid-fire cannon and four machine guns, and aided by searchlights and infrared night-viewing devices, the Hammer team also was carrying special ammunition that would explode on hitting the pavement.

The briefers assured the president that the spectacle of the AC130s laying down a carpet of bullets would frighten off even the most zealous Iranian.

While the main Delta team hit the embassy, another squad would hit the ministry of foreign affairs, where three ranking diplomats were being held. The ministry was in the middle of a cloister of government buildings. However, the area would be virtually deserted on Friday night. The buildings was considered to be lightly guarded and easy to enter. Two helicopters were to pick up the team and fly south to Manzariyeh.

The helicopters and AC130 would fly for 38 minutes south from Tehran toward the deserted Manzariyeh airfield secured by a team of Rangers. There they would board three C141 transports, two of which were flying hospitals, and head south and then west over the Persian Gulf, across Saudi Arabia and on to Egypt.

There also were Iranian air bases with F4 fighter-bombers purchased during the shah's regime. They were clearly within striking distance of the route of the cumbersome helicopters and AC130. The F4s at the Tehran airport posed a particular threat, since it was directly on the route south.

The Pentagon planners knew that the Iranian pilots had never been trained in night fighting. Still, the possibility that some planes would attempt to interdict the force in the nearly three hours it would be in Iran before exiting could not be ignored.

To combat the threat from Iranian warplanes, U.S. electronic warfare planes would be in place not only to jam radar and communications but to detect when the F4s were about to take off.

They would be able to order in a portion of the 48 F4s and A6Es off the carrier Coral Sea and 24 A6Es from the Nimitz to bomb Iranian runways. A dozen A7Es from each of the carriers could provide additional cover against Iranian ground forces. And if planes should get off the ground, the 24 F14s from the Nimitz could join the F4s in intercepting Iranian planes.

If possible, the plan was to minimize the damage to Iranian airfields so that they would not be vulnerable to attack by some other regional force. The superior equipment, such as special night-flying vision devices available to the better trained American pilots, should make the contest no match.

The White House had prepared a message to the Russians to explain the rescue mission if there was any indication that the Soviets were, in the words of one Carter aide, "getting the wrong idea that this was anything more than just a hostage rescue."

If Soviet forces made a move, the U.S. was ready to call in additional forces from Europe and two carrier groups sailing toward the Indian Ocean.

When Gen. Jones and his briefers finished describing these plans at the April 16 meeting in the White House Situation Room, they introduced Beckwith. Beckwith assured the group that there was no team better suited for the task--anywhere.

Carter asked lots of questions and wondered if there were anything more he could do to assure the mission's success.

Jones was blunt, according to the notes of one participant. "We want to answer all your questions now, Mr. President, and not be bothered with questions about why not do this, why do that" during the mission.

"Once you start," Carter pledged, "I'll stay out of your business."

After the meeting, Jordan approached Vance, who had opposed the mission on the grounds that it would not work, while negotiations combined with economic sanctions eventually would. Jordan asked the secretary if he felt better about the plan.

Yes, he replied, but indicated he still opposed it. "Don't forget, I was at the Defense Department for years and the military will never tell you they can't do anything."