Former Central African emperor Bokassa spent all day today locked up inside his airplane on the runway of a French airbase as the French government tried to find another country willing to grant him asylum.

"We have inquired on several continents," said a French official as his government continued to grapple with the problem of getting rid of the dictator whom it helped overthrow Thursday night.

French officials no longer are even trying to deny that France organized the successful coup, staged while Bokassa was out of the country, ostensibly on a mission to seek financial aid from Libyan ruler Muammar Qaddafi.

U.S. State Department spokesman Hodding Carter's only comment on the coup -- "Vive La France." -- was noted here with both pleasure and amused expressions of suspicion that it also was meant as a sly dig.

Although he may wind up back there in the end, Libya apparently does not want Bokassa. Informed sources said it had not answered France's request that it take him back.

The French have not permitted anyone to leave Bokassa's plane since it landed at about 8 p.m. yesterday. Bokassa's son, Georges, 29, drove from Paris to the airfield at Evreux in Normandy to meet his father, but the heavy French guard around the plane refused to let him aboard.

The French have communicated by radio with the plane and its crew. Bokassa is said to be insisting on his right to disembark, since he is a French citizen. The French government is trying to get around that legal difficulty by suggesting that he had forfeited his citizenship by serving as a foreign chief of state.

Since France's African colonies gained their independence in 1960, the French have been involved in many overt and covert military operations in their former empire, but this was the first time French forces overthrew a government that Paris recognized diplomatically.

French officials stressed that President Valery Giscard d'Estaing had acted because of Bokassa's systematic violations of human rights. Giscard had publicly criticized President Carter for invoking human rights in international relations.

The French have been shifting their policies on human rights in Africa with the frankly stated objective of garnering the support of the Organization of African Unity for a number of broad French goals, such as establishment of a permanent "trialogue" of western Europe, the Arab world and Africa as a counterweight to the influences of the United States and the Soviet Union.

Another sign of the French policy shift was an unpopular ban on a tour of France by the Springboks, South Africa's national rugby team. The French previously had insisted that South Africa's racist policies were an internal matter of no direct concern to the French government.

There are suggestions here that the French speeded up their operation against Bokassa because they feared the United States might upstage France by breaking diplomatic relations with the former Central African Empire.

Reliable sources here confirm French press reports that Giscard also acted because Bokassa had become personally intolerable to him. This view is supported by an incident that allegedly took place Aug. 1, when Giscard's chief aide for African affairs, Rene Journiac, met with Bokassa to try to persuade him to abdicate quietly.

Bokassa, according to this account, threatened to hit Journiac with his imperial cane, a threat he has often carried out against others in the past. The meeting took place in Gabon, in the presence of Gabonese President Omar Bongo. When Giscard heard of the threat and telephoned Bokassa to complain, Bokassa hung up on him, the sources say.

The man Bokassa allegedly threatened is little known to the general public, but he is the chief administrator of French political interests in Africa, with all that implies in the control of money, intelligence and military forces. Journiac is, an Elysee official recently said, "The most powerful man in Africa."

The French say they decided to restore David Dacko to the presidency of Central Africa because he incarnated legitimacy, having been regularly elected the country's first president, then overthrown by Bokassa in midterm.

Dacko said today that several African presidents had approved of the coup in advance. This group is understood to include Gabon's Omar Bongo, the Ivory Coast's Felix Houphouet-Boigny, Senegal's Leopold Senghor, with whom Giscard recently spent a weekend in Normandy, and Zaire's Mobutu Sese Sekou, who called on Giscard on the eve of the coup for the second time in a week. Mobutu said today that he met with Dacko three weeks ago.

Bokassa's prime minister, Henri Maidou, whom Dacko named his vice president, evidently was also in on the coup from the start. One reliable source said a phone call from Maidou to Paris alerted the plotters that Bokassa had left the country for Libya for 48 hours, and it was safe to set the operation in motion. There are suggestions that Dacko left Paris after that call.