Salvage workers trudged across a muddy mountainside Thursday searching for bodies and clues to explain why a pilot steered his Boeing 707 straight into the peak, killing all 144 people aboard.

At least 90 bodies have been recovered, along with one of the jet's two flight recorders, said Olivia Baptista, a spokeswoman for the Vila do Porto town council."There are no survivors," she said. She said 40 to 50 bodies were found Thursday and 50 were found Wednesday, shortly after the crash.

The smell of oil hung in the damp air, and a light rain fell on debris that included playing cards, a book of fairy tales and vacation clothing, still neatly folded.

The U.S. charter plane, carrying 137 Italian vacationers and a seven-member American crew, was preparing for a refueling stop on Santa Maria island when it slammed into 1,794-foot-high Pico Alto mountain. It was headed to the Caribbean.

Civil aviation officials said the 20-year-old jet had a history of minor service problems.

Access to the wooded crash site was very difficult, said Jose Martins Freitas, chief of the Azorean rescue services. "The ground is slippery, and it's foggy," he said.

The Italian government sent a plane to the Azores with medical personnel and firefighters to help salvage efforts, and the Vatican said Pope John Paul II issued a message of sympathy for relatives of victims.

Witnesses said the plane hit a slope, bounced over a road, lost an engine and crashed into the mountain. Bodies were spread in an area with a 1.8-mile radius about 24 miles northeast of the airport.

Construction worker Jose Barro said he and the village priest heard the crash and ran to the site. "We tried to find someone alive to get them out," he said. "But we only found dead bodies."

Mayor Jose Humberto Chaves of Vila do Porto said the aircraft was making "normal maneuvers" preparing to approach the airport's main runway but should have been at 3,000 feet and was "much too low."

The jet's pilot had not reported any trouble in a radio conversation with the airport three minutes before the crash, the Portuguese news agency LUSA reported. Earlier unconfirmed reports said the pilot had requested a runway be cleared for an emergency landing.

"The plane was very low, everything seemed perfectly normal, then it turned and flew straight into the mountain," said Manuel Vairos Figueredo, mayor of the fishing village of Santa Barbara near the airport.

"There was a tremendous explosion. The plane burst into flames and trees around it caught fire. Nobody could possibly have survived," Vairos Figueredo said.

Santa Maria is the easternmost island of the Azores, a Portuguese archipelago 750 miles west of Portugal. The crash site is about 8 1/2 miles from Vila do Porto, capital of the 40-square-mile island.

The jet belonged to Independent Air Corp., a company based in Smyrna, Tenn. The company said the plane was flying from Bergamo, Italy, to the Dominican Republic. It was chartered by the Dominican firm Dominair by six Italian travel agencies.

The Federal Aviation Administration reported fog in the area with a visibility of five miles below 500 feet and scattered clouds at 500 feet.

The craft was one of two Boeing 707s the company owns, said A.L. Pittman, president of Independent Air. He said it had 12,500 cycles, or takeoffs and landings, and fewer than 50,000 hours in the air. FAA spokesman Jack Barker said that was not excessive.

In Seattle, Boeing spokesman Tom Cole said the plane began service in 1968.

FAA records show seven service difficulty reports on the plane over the past six years, agency spokeswoman Bobbie Mardis said.

She said they dated from January 1983, when a report said the plane's No. 2 engine was shut down due to turbine failure.

Several travelers quoted by Italian news media said they had flown on Independent Air Corp. 707s on previous trips to the Caribbean and complained about problems with seats, tray tables and air conditioning in the jets.

Italian state radio said the tourists aboard the flight paid "bargain" prices for the package tour vacation in the Caribbean, "maybe too cheap."