A helicopter-and-truck rescue mission by an American construction firm yesterday transported 77 Americans out of the combat zone in Zaire's Shaba Province, virtually eliminating any need for a U.S. paratroop evacuation mission to Africa.

Alarm about some 2,500 Europeans stranded in the battle area, however, continued to run high. Belgian Foreign Minister Henri Simonet told his nation's parliament that Europeans were being hunted down in the rebelheld town of Kolwezi, the heart of the copper mining center in the former Belgian Congo.

Diplomats in Zaire said that at least 11 foreigners had been killed so far in the fighting, now in its sixth day, including four Belgian mining officials and an Italian. A French Embassy counselor in Kolwezi said in a radio broadcast that "the rebels have gone a bit wild . . . They are shooting all over the place . . ."

Although 1,500 troops of the American 82nd Airborne Division will remain in a precautionary state of alert, Carter administration officials said, there is no current expectation that they will be used except possibly to help evacuate Europeans. About 13 Americans reportedly remain in the the embattled area around Kolwezi, plus about 2,000 Belgians, 400 French citizens, and about 174 British and Commonwealth nationals.

Zairian paratroopers, originally Israeli and French-trained, yesterday reportedly recaptured the military airport of Kolwezi from rebel forces who staged a surprise attack from across the Angola border on the night of May 11-12, the Zaire news agency, AZAP, announced.

There were continuing reports yesterday that some officials of the Carter administration are anxiously seeking a way to make a show of force against the major Cuban military presence in Africa, supported by Soviet weaponry.

Tere is no tangible evidence, U.S. officials concede, that Cuban troops are among the so-called "Katanga gendarmes" who are the attackers in Shaba Province, although U.S. officials say they believe these troops were trained by Cubans in Angola.

There is talk in Washington that some officials are anxious to provide clandestine support to the anti-Marxist guerrillas led by Jonas Savimbi who have continued to fight on in Angola since that nation's 1975-76 civil war. That conflict officially ended in a victory for President Agostinho Neto's Popular Movement for the Liberation of Angola, supported by the Soviet Union and Cuba, but about 20,000 Cuban troops remain to help fight Savimbi's guerrillas.

"We don't discuss contingency plans," said one official. Under legislation known as the Clark Amendment, sponsored in 1976 by Sen. Dick Clark (D-Iowa), chairman of the Seate Foreign Relations Subcommittee on Africa, clandesine U.S. aid to anti-Marxists in Angola was cut off and the United States is prohibited from further military involvement in Angola.

Sen. Robert Dole (R-Kan.) yesterday introduced a bill to modify the Clark Amendment, saying his modification "would make it absolutely clear" that the original amendment in no way restricts U.S. assistance to neighboring Zaire.

A senior U.S. official strested yesterday that there never was any intention to deploy American airborne troops to Zaire for anything but a mission to rescue civilians. That requirement, for Americans, "appears to have passed," he said, as a result of the evacuation conducted overnight for employes of Morrison-Knudsen International, a construction firm based in Boise, Idaho.

Using a truck convoy to transport 65 Americans, and a helicpter to pick up 12 others, Morrison-Knudsen transferred the Americans from the Kolwezi region to Musonoi, a camp 52 miles north of Kolwezi and well out of the combat zone.

Morrison-Knudsen has been building a 1,020-mile electricity transmission line from Zambia across Zaire. In the evacuation, company spokesman Bob Smith said, "Everything went off very well," without any exposure to firing.

Thirteen Americans were left behind in Kolwezi, including several whom reportedly chose to remain, missionaries, and "a nurist" - some of. Other reports, however, refer to foreign nationals being held in Kolwezi as "hostages."

Kolwezi is almost 1,000 miles from Kinshasa, the capital at Zaire, but the most vivid, although second-hand, account of the confusion on the fighting scene came from Kinshasa. IT was in the form of a telephone conversation between a French Emassy counselor and the Europe One radio station.

The counselor said that in Kolwezi eight Belgians and one Italian were killed. "For the moment we know nothing about any losses in the French colonoy," he added.

"We have the impression that the rebels have gone a bit wild," he said. "They have been pillaging and they have been killed. They are shooting all over the place and . . . it seems that they are no longer under very strict discipline.

"We have gained the impression that the whole of the European colony there is really in the position of being hostages," he said. "It seems that the attackers have separated the able-bodied men from their families" with women and children ordered to stay in private homes with the men assembled elsewhere.

The British Foreign Office said that the United States, France and Belgium will act together if foreigners have to be evacuated. French Air Force cargo planes were reported to be on standby alert. In Belgium, Foreign Minister Simonet said the situation is especially confused because "the Zairlan armed forces are not, shall we say, up to conducting a regular battle . . ." However, he said, "There is no question of undertaking an [evacuation] operation without" Zaire government approval.

State Department spokesman Hodding Carter III said the Zaire government now has made a specific request for the United States to send emergency aid beyond the $17.5 million level of military assistance scheduled for that nation.

Zaire has asked for "spare parts, medical supplies, communications equipment and petroleum supplies" in "relatively modest amounts," Carter said.

There is a legislative tangle, however, Carter said, because Zaire currently is "technically ineligible" to draw against U.S. credits because it is in arrears on repayment of its loans. Carter called this "a relatively minor matter that can be cleared up with the Zaireans." Under legislation sponsored by Sen. Edward W. Brooke (R-Mass.) in 1976, this barrier can be overcome if nations in arrears on loan payments take "appropriate steps" to clear the default.