Stewart's Learjet 35 According to the FAA, Stewart's 23-year-old, eight-passenger plane had logged more than 10,000 flight hours and had no history of serious mechanical problems

October 27, 1999
Web posted at: 12:08 a.m. EDT (0408 GMT)

In this story: Recovery of remains is top priority Cabin pressure valves Cockpit voice recorder probably silent 23-year-old jet advertised in 'premium condition' No test to prove oxygen deprivation Memorial service for Payne Stewart RELATED STORIES, SITES

MINA, South Dakota (CNN) -- Investigators plan to use heavy equipment Wednesday to find and recover pieces of the Learjet that nose-dived into the ground with golf champion Payne Stewart and five others aboard.

"That will be slow going," National Transportation Safety Board Vice Chairman Bob Francis said Tuesday night, "because of the difficulty of working in the crater, how deep it is and the fact that everything is mixed in with the earth."

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The jet hit the ground with a force that broke it into thousands of pieces and created a crater 10 feet deep.

Small parts of the aircraft's pressurization and oxygen systems have been located.

Recovery of remains is top priority

Investigators spent their first full day at the site Tuesday, searching the ground outside the crater for human remains and identifiable pieces of the plane.

It was a grim task, performed in a soggy cow pasture with a cold wind blowing.

"The teams are working together," said Francis. "Obviously, the forensics has a higher priority. But you try to do it in a way that you give that priority without disadvantaging the accident investigation."

All collected human remains will be sent to Sioux Falls, South Dakota, for identification by the medical examiner. The FBI is assisting in the recovery and identification, said Francis.

He also said plane wreckage would be moved to a hanger at the Aberdeen Airport to give system investigators time to study the parts.

"The issues are: What was damaged, what might have been an issue prior to impact and if there's any possibility that the impact cleared a piece of the system that had been a problem previously," Francis said.

Officials have cautioned that there will be no quick explanation for why no one was conscious at the controls for four hours Monday, when the jet flew 1,400 miles from Florida to South Dakota before running out of fuel and slamming nose-first into the ground.

Investigators have asked that anyone who shot amateur video of the plane's flight should come forward with the tape.

Cabin pressure valves

A new question surfaced Tuesday about whether upgraded valves regulating cabin pressure were installed in the Learjet as required by a directive from the Federal Aviation Administration.

Sudden decompression is being investigated as a possible contributing factor in Monday's crash. Stewart and five other people died. The FAA directive, issued January 3, 1995, covered the type of Learjet involved in the crash.

The president of the charter company that owned the doomed aircraft, James Watkins, said he was not personally aware of the FAA's directive, and it was not immediately clear if the plane had received the upgrade.

The FAA directive tells Learjet owners to replace valves "to prevent rapid decompression of the airplane due to cracking and subsequent failure of certain outflow/safety valves."

Owners had 18 months to comply with the directive. Sunjet purchased the plane after any such maintenance would have been completed in order to comply with the directive.

Nonetheless, a Sunjet spokesperson, who declined to identify himself, said, "Obviously if it was an (FAA directive), we would have had to comply with it ... Absolutely."

The FAA also limited planes to an altitude of 41,000 feet until the valves were placed because of the possibility they could fail.

In the plane's last radio transmission above Gainesville, Florida, the pilot was instructed to climb to 39,000 feet.

Later, the plane, apparently on autopilot, cruised 1,500 miles straight up the nation's midsection, across half a dozen states. Authorities say the plane was "porpoising," fluctuating between 22,000 and 51,000 feet.

Cockpit voice recorder probably silent

Investigators had not yet retrieved the plane's cockpit voice recorder.

Even if found, however, the device may not hold the answers. The tape in the voice recorder recycles every half hour meaning it is unlikely to still contain information about the first half hour of the flight when the jet is believed to have had problems.

Stewart and the others on the plane presumably were already unconscious or dead by the last half-hour of the flight.

The jet did not have a flight data recorder.

23-year-old jet advertised in 'premium condition'

In addition to the federal investigators at the crash site, another team went to Florida, where the flight originated and the Learjet was based.

"We're asking (Sunjet Aviation, the company that owns the plane) for records on service difficulty reports and other records of this aircraft," Francis told CNN.

"We're (also) looking at our own records for any incidents or accidents (involving Learjets) that we've got records of that may be relevant," he said.

Sunjet Aviation, located in Sanford, near Orlando, said it had purchased the Learjet 35 about a month ago. It was built in 1976 and had a good maintenance record, according to the Federal Aviation Administration.

The Sunjet web site had listed the airplane as being for sale. It was described as being in "premium condition inside and out."

The company described both pilots of the chartered, twin-engine plane as experienced -- Michael Kling had 4,000 hours flying time while co-pilot Stephanie Bellegarrigue had 1,700 hours.

According to the NTSB, Kling -- a former military pilot -- had 37 hours flying time on this particular type of aircraft and had just been rated for the Learjet one month ago. The agency said Bellegarrigue had 250 hours in both the Citation and Learjet.

No test to prove oxygen deprivation

The possibility that the plane suddenly lost cabin pressure, causing the occupants to pass out and possibly die, is just one theory investigators will consider, Francis told CNN.

"There are lots of places where there are openings to the outside atmosphere in an aircraft," he said, "so those are the kinds of things that we'll be looking for."

Some tissue samples from the victims' remains were removed from the scene. Brad Randall, a special state medical examiner, said they would be tested for substances such as carbon monoxide, but there is no specific test that can be done on samples that would show oxygen deprivation.

The Learjet 35 left Orlando at 9:09 a.m. Monday and, within minutes, air traffic controllers lost contact with it, leading to speculation the plane may have suddenly lost cabin pressure soon after taking off for Dallas.

Planes that fly above 12,000 feet are pressurized, because the air at altitudes above that lacks enough oxygen for comfortable breathing. If a plane loses pressure at higher altitudes, those aboard could slowly lose consciousness or, if an aircraft broke a door or window seal, perish in seconds from lack of oxygen.

Once reaching a cruising altitude, pilots often switch on the autopilot. If they pass out, the plane could continue on until it ran out of fuel.

Fighter jets sent after the Learjet followed it for much of its flight but were unable to help. The pilots drew close and noticed no structural damage but were unable to see into the Learjet because its windows were frosted over.

Officials said at the altitude the plane was flying, the air temperature would have been minus 70 degrees.

The FAA routed air traffic around the Learjet and kept planes from flying under it.

Memorial service for Payne Stewart

Stewart's 10-year-old son collects flowers left by well-wishers at the family home in Orlando, Florida

A memorial service for Stewart, who lived in Florida, was scheduled for 11 a.m. Friday at the First Baptist Church in Orlando.

With his traditional knickers and tam-o'-shanter hat, Stewart, 42, was one of the most recognizable players in golf. He had won 18 tournaments over his career, including two U.S. Open titles.

He also was part of the team that helped the United States stage a historic comeback to beat Europe for the Ryder Cup last month.

When the crash occurred, Stewart was on his way to Texas for a business meeting on a proposed golf course near Dallas and to play in this week's Tour Championship tournament in Houston.

Although the show will go on at the Champions Golf Club, the pro-am event Tuesday was canceled. But PGA chief operating officer Henry Hughes said the 72-hole tournament will resume later this week. Tour officials are making black ribbons for everyone to wear in Stewart's memory.

Stewart and his wife, Tracey, had two children, Chelsea, 13, and Aaron, 10.

Correspondents Leon Harris, Charles Zewe, Susan Candiotti and The Associated Press contributed to this report.

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