The lawsuit, brought by the families of Stewart and his close friend and agent Robert Fraley, who also died, could result in a jury award worth millions if the planes manufacturer is found to be at fault.
Or testimony could show that a lack of pilot training and plane maintenance caused the Learjet 35 to lose pressure soon after takeoff from Orlando, killing all aboard within minutes. The plane then began an eerie journey across America before running out of fuel and nose-diving into a South Dakota pasture.
The case, which began Tuesday, is expected to take six weeks to argue.
The Oct. 25, 1999, crash came months after Stewart won the U.S. Open, his third major championship. That victory was one reason an attorney for the families calculated that Stewart, who was 42, could have earned more than $200 million in winnings, endorsements and other ventures if his career had not been cut short.
The evidence is going to show this case is first and foremost about trust and responsibility, said Daniel Barks, a lead attorney for the families. Learjet violated that trust. ... They wagered the lives of Bob Fraley and Payne Stewart.
Barks will try to pin the crash on defects within the outflow valve and its adapter, which sit near the front nose of the aircraft. The valve helps maintain pressure in the cabin during flight and depressurizes a plane upon descent.
Barks said poor design, lack of testing and weak materials caused the adapter to fail, exposing a 3-inch hole and allowing depressurized air into the cabin.
Learjet attorneys dont dispute that the cabin lost pressure that day, but they say the valve adapter worked as it should have.
This adapter did not fail, said Robert Banker, attorney for Learjet. Theres nothing wrong with that adapter.
Bankers team notes the part was approved by the Federal Aviation Administration and remains in more than 300 aircraft. The part has no history of failures, the defense contends.
Learjet will try to blame Sunjet Aviation, the planes operator, which closed not long after the crash, with failing to maintain the aircraft. They pointed out a history of problems the company had with maintenance and finances.
And the attorneys said Sunjets pilot, Michael Kling, had not been adequately trained and perhaps could not respond to a rapid depressurization quickly.
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