The remains of eight American servicemen killed during the ill-fated rescue mission in Iran 11 days ago were flown to Switzerland today on their way home to the United States.

Greek Catholic Archbishop Hilarion Capucci accompanied the remains to Zurich aboard a Swissair flight.

In Zurich, the remains will be turned over to the Swiss government and the Geneva-based International Committee of the Red Cross, which will cooperate with U.S. government officials in returning them to their families in the United States.

Iranian authorities had insisted that the United States government be kept out of the procedures which, along with the labyrinthine bureaucratic problems involved in embalming the remains, were described by one knowledgeable source as "Kafka-cubed."

Capucci, Swiss Ambassador Erik Lang and Papal Nuncio Annibale Bugnini yesterday signed papers at the Tehran morgue permitting the remains to be transferred to the airport in the archbishop's keeping.

Informed sources said the remains were placed in nine lead-lined caskets specially flown in from Switzerland last week.

The United States insists that only eight men were killed when a helicopter and a C130 fuel tanker collided and exploded in the desert rescue operation.

The nine caskets apparently were used because Ayatollah Sadegh Khalkhali has maintained that nine Americans were killed in the incident.

Informed sources said, however, that the Tehran coroner could only account for eight men, despite the recent discovery of more remains at the site of the accident.

The sources said that because of the condition of the bodies, only three of the victims could be identified by their dog tags.

Meanwhile, the spokesman for the Iranian joint chiefs of staff last night announced that authorities had located the final American helicopter used in the rescue effort.

After suggestions at midday that the United States had made a new helicopter incursion far inland -- based on nomads' claims that they had sighted four unidentified helicopters flying overhead Sunday -- the spokesman said that the downed helicopter was part of the failed rescue operation.

The helicopter was found abandoned in the desert about 370 miles southeast of Tehran, along the route taken by the ill-fated American rescue mission. It had been forced down because of technical failure and a companion craft picked up the crew.

The spokesman said maps and documents had been found in the helicopter, which will be transported to Tehran.

The student militants holding the hostages announced last night that they had transferred more Americans to three additional cities -- Kerman, Arak and Mahallat.

Earlier, as part of their plan to disperse the Americans in the wake of the abortive rescue operation, the militants had said they had sent other hostages to eight provincal cities as well as keeping some at the embassy itself.

Meanwhile, President Abol Hassan Bani-Sadr yesterday proposed a five-nation inquiry into the Soviet intervention in Afghanistan. In a meeting with visiting Cuban Foreign Minister Isidoro Malmierca, the Iranian president said three Moslem and two non-Moslem nations should be represented in the investigation.

But both he and Foreign Minister Sadegh Ghotbzadeh stressed Iran's condemnation of the Soviet invasion. The foreign ministers said the only solution was Soviet military withdrawal from Afghanistan.