Stewart Plane Black Box Found

Investigators have uncovered what they hope will be a crucial clue as to what caused the plane crash that killed golfer Payne Stewart and five others, reports CBS Affiliate Station KELO-TV in Sioux Falls, South Dakota.

Recovery crews found the "black box" among the wreckage of the Learjet that crashed in a field Monday near Mina, according to Bob Benzon of the National Transportation Safety Board.

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Model of the Learjet that crashed in South Dakota.

Federal investigators say the cockpit voice recorder may have picked up sounds at the end of the flight that could shed light on what was happening inside the plane. Though the Learjet had no flight data recorder that could provide mechanical information, the cockpit voice recorder has a 30-minute loop that usually records over itself.

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Officials are trying to find out if the Learjet's cabin suddenly depressurized, causing everyone aboard to black out. The jet crashed four hours after leaving Florida. Investigators are trying to determine how the plane flew 1,400 miles across the country, apparently without someone at the controls.

Benzon said investigators want to recover various parts of the plane's pressurization system, such as door and window seals and valves.

Many Sports Figures Have Died In Plane Crashes

March 31, 1931 Knute Rockne, Notre Dame football coach, in Kansas.

Oct. 30, 1954 Wilbur Shaw, President of Indianapolis Motor Speedway, in Decatur, Ind.

Feb. 16, 1961 18 members of the U.S. figure skating team, in Belgium.

Feb. 15, 1964 Ken Hubbs, 22, Chicago Cub second baseman, in Utah.

July 24, 1966 Tony Lema, 1964 British Open champion, in Munster, Ind.

Sept. 26, 1969 25 members of Bolivian soccer team "The Strongest", in the Andes.

Oct. 2, 1970 14 Wichita State football players, in Colorado.

Nov. 14, 1970 37 Marshall University football players, in Huntington, W.Va.

Dec. 31, 1972 Roberto Clemente, Pittsburgh Pirate outfielder, from San Juan, Puerto Rico en route to Nicaragua to aid earthquake victims. Aug. 2, 1979 Thurman Munson, New York Yankee catcher, in Canton, Ohio.

July 19, 1989 Jay Ramsdell, CBA Commissioner, in Sioux City, Iowa.

April 1, 1993 Alan Kulwicki, NASCAR's 1992 champion, in Blountville, Tenn.

April 18, 1996 Brook Berringer, Nebraska quarterback, two days before the NFL draft, when the small plane he was piloting crashed in Raymond, Neb.

He said one of the crucial valves on Stewart's doomed plane had been replaced the Saturday prior to the incident.

He said the valve was changed to balance engine thrust on the plane Â— not because of any prior problem with cabin pressure. After the replacement, the plane pressure-regulation system worked fine during a short flight on Saturday, he said.

Benzon said he does not know whether such a valve has ever been a factor in a crash.

By Wednesday evening, investigators had removed more than half the wreckage from a crater that initially was 10 feet deep. Crews also found several passenger oxygen masks and both the jet's engines inside the main impact point - a 10-foot deep, 30-foot wide crater.

Federal officials are also looking into three other incidents involving Learjets that crashed under circumstances similar to Stewart's, The New York Times reported Thursday.

Benzon acknowledged there were similarities between the Stewart crash and the other incidents, but told The Times "that oxygen deprivation isn't the only thing that could have happened."

Meanwhile, the 29 players in the Tour Championship field, PGA Tour officials and hundreds of fans gathered around the first tee at 7:45 a.m. Thursday for a memorial service for Stewart. Tom Lehman offered a prayer. A lone bagpiper walked down the fairway.

Payne Stewart
Career Highlights

"If we're not playing golf, I don't know how else we can honor him," PGA Tour commissioner Tim Finchem said. "There's not much of a forum to remind people about Payne. This provides us a way to tell what he was all about."

"He will still live on definitely in golf," golfer Davis Love III said, "but he will live on as a great father."

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