Three jetliners took off successfully from New Orleans' Moisant Airport about 10 minutes before Pan American World Airways Flight 759 lifted off in a thunderstorm and crashed into suburban Kenner last Friday, federal safety investigators said today.

One of the planes, a Delta Air Lines DC9 bound for Baltimore-Washington International Airport, was cleared for takeoff about seven minutes before the Pan Am jet in the same direction and on the same runway, a 9,200-foot, east-west strip whose eastward flight path extends over Kenner.

Two other flights, a Republic Airlines DC9 and a Texas International Airlines DC9, were cleared on a north-south runway just after 4 p.m. local time. The Pan Am plane, officials said today, was cleared for takeoff just after 4:06 p.m. and crashed about four minutes later.

Pilots of a USAir jet next in line to take off after Pan Am told safety investigators that they saw smoke on the horizon after Flight 759 departed. Air controllers shifted the USAir plane to another runway, and it took off a few minutes later.

All 145 people aboard the fully loaded Pan Am flight and eight persons on the ground were killed when the Boeing 727 crashed into a residential area.

Fierce winds have emerged as a prime suspect in the crash, and National Transportation Safety Board teams were interviewing pilots of the Delta jet last night in an attempt to obtain helpful accounts of flying conditions.

Investigators disclosed Sunday that minutes before the accident, the airport tower broadcast two warnings that "wind shear," dangerous shifts in wind speed and direction, might be encountered near the airport.

Safety board investigators said today that there is strong evidence that the warnings were broadcast on a frequency heard by taxiing planes and on another frequency heard by incoming and departing aircraft, increasing the odds that the Pan Am crew was forewarned.

Questions about whether air controllers, who are employes of the Federal Aviation Administration, took adequate steps to convey the wind-shear alert to the pilots could become an important issue when liability for the crash ultimately is settled in the courts, aviation specialists said.

As bulldozers and about 1,000 workers continued to clear wreckage and rubble from the three-block area devastated by Flight 759, new details emerged about the weather conditions that its three-man crew faced on takeoff.

Weather radar showed a "Level 2," or moderate, storm northeast of the airport near the time of the accident. Radar also showed a "Level 5," or intense, storm southwest of the airport. The Pan Am plane took off on an east-southeast heading.

Seven minutes before the accident, an observer in the control tower recorded heavy rain and visibility of two miles, with 14-knot winds gusting to 20 knots.

Thunderstorms are common occurrences in New Orleans at this time of year, and planes routinely take off and land as rain falls. As moderate rain fell today, jets swooped low over clean-up crews at the accident site and landed on the runway used by Flight 759.

At the airport, meanwhile, investigators laid out wreckage from Flight 759 on a parking lot and continued to examine engines, control surfaces, hydraulic systems and other pieces, seeking clues to the cause of the crash.

"It's a very painstaking process of a jigsaw puzzle, finding those pieces," said NTSB vice chairman Patricia Goldman, who is overseeing the investigation.

In a makeshift morgue at a Delta hangar at the airport, pathologists continued trying to identify crash victims today. Only 10 bodies have been identified, a spokesman for the Jefferson Parish (county) coroner's office said.

Relatives were not allowed in to identify the bodies, which were being released for burial individually as they were identified.

The first funeral of a crash victim took place today when Lisa Baye, 6, was buried at a local cemetery in a private ceremony. One of the eight killed on the ground, she died of burns Saturday.

Meanwhile, clutching a teddy bear clad in a T-shirt proclaiming "God Loves You," 16-month-old Melissa Trahan was given an excellent prognosis for burns suffered in the crash. She had been found buried under a mattress in her house where her mother and sister were killed.

"She's doing fine," Dr. Gustavo Colon said at a news conference at East Jefferson General Hospital. "She's a spunky little girl who has been injured, but she's healing. She's reacting quite well." Cuts were visible on her hands, legs and forehead.

Pilots know the three-runway Moisant Airport west of here near Lake Pontchartrain as a moderately busy air center with approach and landing patterns that present no particular difficulty.

The airport was not large enough to be among the 22 hub airports at which the Federal Aviation Administration restricted traffic after last year's strike by air controllers.

In Washington today, technicians continued to work on the jet's two flight recorders. Voices on the plane's cockpit tape are extremely faint, which investigators blame on poor maintenance and the machine's age.

NTSB members are considering issuing a recommendation that airlines modernize their planes' recorders, Goldman said.