Soviet ballerina Ladmilla Vlasova departed for Moscow today after meeting with U.S. officials and satisfying them that she was leaving the United States voluntarily, despite her husband's defection here last week.

Vlasova gave U.S. officials no message for her husband, Bolshoi star Alexander Godunov, nor did she express any desire to see him, diplomat Donald F. McHenry told reporters after meeting with her for 25 minutes. The meeting took place aboard a mobile lounge docked beside the Aeroflot jetliner on which the ballerina and other Moscow-bound passengers had been sitting since Friday at Kennedy International Airport.

"She was asked whether there was anyone she wished to see or anything she wished to do before she left," McHenry said.

"Her answer was 'nyet,'" the deputy United Nations ambassador said.

After the meeting aboard the mobile lounge, which is like those used at Washington's Dulles Airport and belongs to the New York-New Jersey Port Authority, U.S. officials gave permission for the Aeroflot plane to depart. Port Authority police officer Carl Diraimondi had blocked its wheels with his car minutes before its scheduled departure Friday.

The Ilyushin 62, carrying Vlasova and 52 other passengers, took off at 6:38 p.m., 73 hours and 38 minutes late.

McHenry and five other Americans met Vlasova and six Soviet officials aboard the mobile lounge, which remained attached to the Aeroflot plane during their conversation.

"We are satisfied that the principle involved in this incident has been upheld," McHenry said.The ambassador said that the meeting, despite the presence of Soviet officials and the proximity of the Aeroflot plane, was in the "non-coercive" atmosphere the United States had sought from the beginning.

The back stairs of the mobile lounge were left down throughout the conversation, which was translated by a State Department interpreter. Presumably, Vlasavoca could have walked down those stairs with the Americans if she wished.

A White House spokesman said that President Carter was kept abreast of all developments and that "the basic policy was his decision."

McHenry was asked whether the three-day confrontation with the Soviets was worthwhile since the ballerina had told a U.S. official on the plane Friday night the same thing she said today.

"Upholding the right of an individual to express her views is worth it," McHenry replied.

The United States informed the Soviet embassy in Washington Thursday and Friday, the first two days after Godunov's defection, that Vlasova could not leave the country until she had been interviewed to determine her wishes. Nevertheless, Soviet officials escorted her to the airport and onto the jetliner Friday evening.

McHenry laid the blame for the long delay at Kennedy on the Soviets. "This was a simple process that could have been accomplished quickly," said Andrew Young's deputy, who has been mentioned as a successor to the just-resigned U.N. ambassador.

The circumstances of the meeting aboard the mobile lounge were suggested by the United States almost at the outset of the long negotiations, McHenry said.

"I have no idea why they changed their mind," McHenry said of the Soviet negotiators.

The United States appeared to have given some ground, however. McHenry said Saturday that the talks had to take place off the plane, but Sunday he said this was not necessary as long as the atmosphere enabled Vlasova to express herself "freely and calmly."

One of the Americans who accompanied McHenry to the mobile lounge meeting was Godunov's lawyer, Orville Schell, who told reporters repeatedly over the weekend that Godunov was certain his wife wanted to stay in the United States with him.

After the meeting, Schell said he was satisfied with the U.S. government's efforts and agrees with McHenry completely. Schell said Vlasova gave him no message for her husband.

The 36-year-old ballerina spoke of her husband during the mobile lounge meeting, but only mentioned that he had defected and had let two days go by without contacting her.

Godunov, a 30-year-old Bolshoi star who is expected to follow defectors Rudolph Nureyev and Mikhail Baryshnikov to stardom in the West, had discussed defecting several times with his wife, according to Schell.

In their last talk on the subject, while the Bolshoi was in Canada just before coming to New York on its current U.S. tour, Vlasova showed reluctance, but did not reject the idea of defecting, Schell said.

Godunov took an opportunity to contact U.S. officials while he was separated from his wife and then, apparently, asked officials and Schell to help his wife join him.

Schell said Godunov, who remained with friends at an undisclosed location in the New York area, was so concerned by the drama at Kennedy Airport that he could hardly sleep.

Asked today why Vlasova would want to get off the plane, he replied, "She has a husband she loves and they've talked about having a family." The couple has no children.

The long stalemate at Gate 10 of the Pan Am terminal moved rapidly to its conclusion after McHenry and the Soviet deputy U.N. ambassador, Yevgeny N. Makeyev, held a last meeting shortly before 2 p.m.

McHenry's emergence from the Pan Am first-class lounge, where he had been taking calls from Washington with his aides, drove the roughly 55 reporters and photographers waiting opposite the departure gate into a frenzy.

Their frenzy, in turn, attracted passengers and others killing time in the Pan Am terminal who joined the fray.

For more than 40 minutes, newspeople stood on chairs, shoved one another and exchanged media talk such as "I'm feeding level to him" and desperate queries such as "Jim, is Diana in there?" -- meaning in the middle of the sweating knot in the terminal with its 78-degree thermostat.

They got to see McHenry take off his suit jacket and put it back on. A mysterious woman in burgundy stirred excitement by her arrival carrying a black overnight bag. The excitement waned when she was identified as McHenry's secretary.

At 2:54 p.m., the mobile lounge docked at the right side of the jetliner and McHenry led his party out of the terminal building to the lounge's back steps.

He emerged 26 minutes later without Vlasova.

McHenry said the ballerina did not express annoyance or anger over her three days on the airliner.

"She seemed in remarkably good spirits," he said.

At one point she joked with the Americans, challenging them to say whether she looked like a woman who had been coerced into her decision to depart, McHenry said.

The Americans sat on one side of the mobile lounge and the Soviets on the other, McHenry said. He was directly opposite Vlasova.

U.S. officials said the 52 other Soviet passengers who endured the heat and confinement of the plane with Vlasova, despite U.S. urging that they emerge and take other planes to their destinations, were ordered to remain aboard in solidarity with Vlasova.

Soviet officials said that no order had been given, that the passengers had chosen, as patriots, to stay and support the dancer in her travail.

Originally, 112 people boarded the plane Friday night. Early in the impasse the 44 non-Soviet passengers accepted an invitation to leave. Some of the Soviets were taken off the plane last night.

Pan Am handles ground operations for the Soviet airline at Kennedy and tried to make the passengers comfortable. It ran air conditioning from its terminal rather than use the plane's system, which burns fuel.

Pam Am supplied food as requested, but its workers were not allowed their normal access to the Aeroflot plane to deliver supplies, a Pan Am spokesman said. At the Soviets' request, food was carried to the loading ramp in boxes, then taken aboard by Soviets.

Pan Am has 20 gates at Kennedy. At its busiest time in the evening, the loss of one gate blocked by the Soviet plane caused headaches for Pan Am supervisors, but no serious delays for passengers, the spokesman said.

There was a final delay for Vlasova and her fellow passengers after the international incident had been settled, the television camera teams had folded their tripods, the scene at gate 10 had returned to normal and the jet-liner taxied away from the terminal: A sudden rainstorm so heavy that the plane could not take off held it at the head of the runway. When the rain abated, the plane took off. CAPTION:

Picture 1, DONALD F. McHENRY . . . "we are satisfied"; Picture 2, Ludmilla Vlasova beams after talking with American officials. UPI; Picture 3, On far side of Aeroflot jet is Kennedy airport mobile lounge in which U.S. and Soviet officials negotiated. UPI