The United States today asked the International Civil Aviation Organization (ICAO) council for its strong condemnation of the Soviet Union for shooting down the Korean Air Lines jetliner two weeks ago and killing all 269 people on board.

A majority of delegates to the extraordinary session of the council appeared willing to approve some form of condemnation, but the strength of a possible resolution remained at issue when the council adjourned until Friday.

"Obviously what we want is the strongest possible vote," a U.S. official said. "There are questions about whether the resolution would condemn the Soviet nation or the act."

In addition to condemnation, the United States and others are seeking a full ICAO investigation of the incident, Soviet compensation of victim's families and Soviet assurances that such an attack against an unarmed civilian airliner will not be repeated.

Also before the delegates is a French proposal to start a lengthy process of amending basic ICAO rules so member nations would agree "to abstain from resorting to the use of force against civil aircraft." Current rules say members "should abstain from using weapons."

The ICAO is a United Nations agency that normally deals only with technical aviation matters, such as international navigation rules or aviation noise standards.

Occasionally the ICAO is thrust into superpower politics and, although it is related to the United Nations, no member of its council has a veto. Thus a condemnation resolution may well pass because only the only communist nations on the 33-member council are the Soviet Union, Czechoslovakia and China.

Such a resolution would carry no sanctions, but ICAO officials said it would harm how the Soviets are viewed in international opinion.

In 1973, after the ICAO condemned Israel for downing a Lebanese civilian airliner off course near the Suez Canal, the Israelis apologized and compensated families of the 108 persons killed. That is the only ICAO condemnation resolution in the organization's 39-year history.

Judging from comments by representatives of nations attending this meeting, world opinion of the Soviets has dropped considerably. Further, many nations have imposed temporary sanctions against Aeroflot, the Soviet airline.

Vadim Sazhin, a Soviet representative, told the council today that there is no reason for "the discrimination that has been taken in several countries against Aeroflot."

J. Lynn Helms, chief of the Federal Aviation Administaiton and head of the U.S. delegation, said the Soviets attacked the KAL Boeing 747 without warning although it was clearly a commercial airliner. Soviet delegates responded that the 747 was flying in coordination with a U.S. spy plane and that the 747 failed to answer demands for identification.

That the flight was 310 miles off course and penetrated Soviet air space when downed by a fighter firing two missiles has not been disputed.

The Soviets also repeated here charges that U.S. and Japanese military officials knew the plane was off course but did not warn it.

In prepared remarks, Helms appeared sensitive to that complaint, saying the ICAO's Air Navigation Commission "should study ways to facilitate coordination between civilian and military aircraft and their respective air traffic control systems."

As the Soviet delegates presented their complaint, with the aid of an overhead projector and a pointer, Helms rapidly took notes. At his turn to speak, he said markings on the Soviet chart showed that Flight 007 had traveled 620 miles in 32 minutes, a feat that would require more than twice the maximum speed of a Boeing 747.

Other countries then asked the Soviets to provide copies of the chart. "I cannot promise to provide it immediately," Soviet delegate Ivan Orlovets said. "It will be presented in the U.S.S.R. special commission report."

The Soviets said they have a special commission investigating the incident.