The Supreme Court removed yesterday the last legal barrier to immediate flights by the Concorde supersonic jet transport into New York's John F. Kennedy International Airport.

Air France and British Airways, who have been seeking Kennedy access for their beak-nosed jetliner for more than 16 months, announced that they will begin full commercial service to New York on Nov. 22.

They also plan a limited number of "proving flights," or test runs, to Kennedy, beginning Wednesday. Airline and manufacturing representatives met yesterday afternoon with Kennedy officials to work out details.

This was all made possible by one simple sentence on the court's Monday order list: "The application for a stay . . . is denied."

The Post Authority of New York and New Jersey, which operates Kennedy airport, has sought a Supreme Court ban on Concorde operations there while the Port Authority appealed a lower court ruling. That ruling, by the Court of Appeals for the Second Circuit (in New York), ordered the Port Authority to permit Concorde operations to begin "forthwith."

The Port Authority can still appeal to the Supreme Court, but Concorde operations can proceed along with the legal case.Observers felt there was little long-term hope for Concorde opponents in the Supreme Court, since the justices probably would have left the ban on Concorde in place if as many as four of the nine felt inclined to review the lower court opinion. It takes four votes to accept a case for review.

Port Authority Chairman Alan Sagner said that the appeal would be pursued.

"We want to see quieter aircraft at oour airports," Sagner said, "not noisier ones . . . In this regard the circuit court order to let the Concorde land is a step backwards which we regret and deplore."

Noise-weary citizens living around Kennedy, one of the world's busiest airports, have been vociferous in their opposition to Concorde flights. They have promised that if the plane, which crosses the Atlantic at twice the speed of sound, is permitted to land at Kennedy, its passengers will spend twice as long as their flight time trying to get out of the airport. They have held several traffic-stopping demostrations on access roads leading to Kennedy.

Faced with such vigorous citizen protests, the Port Authority has been reluctant to move on the Concorde issue. At some point its reluctance became illegal, the circuit court had held.

The Concorde has been flying from London and Paris to federally operated Dulles International Airport here since May, 1976, under a test program authorized by the Ford administration. A similar test was approved for Kennedy, but blocked by the Port Authority.

In recent new draft regulations, the Carter administration has proposed that the 16 existing Concords be permitted to land at major U.S. airports, provided they obey a curfew and meet local noise regulations. It will be some months before those regulations are adopted, but the administration has said it continues to support a 16-month test for Concorde at New York.

An Air Force spokesman said that airline would maintain its full-seven-days-a-week service to Washington when it begins serving New York once a day.

A spokesman for British Airways, which also offers seven-days-a-week service to Washington, said it would cut two flights from Washington to begin twice-a-week service to New York, then expand to four times a week to New York with a further reduction in Washington flights.

In New York yesterday, the Port Authority began to hold public hearings on three proposed noise rules. Two of them would have the effect of banning Concorde from Kennedy, the third would permit a three-month test for Concorde there.

Concorde's manufactures, while never denying that their plane is nosiy, have maintained from the beginning that they could meet the present noise standards at Kennedy as they are now enforced against older, noisier jets such as the Boeing 707 and McDonnell-Douglas D-C8.