The family of a woman killed when Comair Flight 5191 took off on the wrong runway and crashed in flames sued the airline Friday, blaming it for the nation's deadliest airplane disaster in five years.

The lawsuit accuses Comair of negligence and says passenger Rebecca L. Adams suffered "conscious pain and suffering" when the plane went down Sunday morning and quickly burned with 49 people still inside.

The only survivor was the co-pilot, who remained hospitalized Friday but was upgraded from critical to serious condition.

The regional jet had left the gate before dawn with 50 people aboard. Somehow, the pilots mistakenly turned onto the wrong runway, one too short for the twin-engine plane, and tried to take off. The plane crashed in a field just beyond Lexington's Blue Grass Airport.

The crash "could not have happened if those having control of the instrumentality had not been negligent," attorney Bobby Wombles of Lexington said in the lawsuit.

Nick Miller, a Comair spokesman, said he couldn't comment on pending litigation.

"Comair extends its heartfelt sympathy to everyone affected by the accident and our focus remains addressing the needs of family and loved ones in cooperating the investigative process," Miller said.

Earlier this week, a Texas law firm ran a full-page ad in the Lexington Herald-Leader promising to get maximum damages for the families of victims who hired it.

Comair, a subsidiary of Delta Air Lines Inc., operates 850 flights to 108 cities daily. Both airlines filed for bankruptcy protection last year.

The Lexington airport board met in a private session Friday morning to discuss "proposed litigation" against it as well. Michael Gobb, the airport director, said at least one family of the victims had told the airport it intends sue.

Federal officials have been looking into how the commuter jet ended up on the 3,500-foot-long runway, the shortest of two runways at the Lexington airport and meant only for small planes.

The taxiway to the 7,000-foot-long main runway had been altered by repaving one week before the crash.

In addition, only one air traffic controller was in the tower. The controller had had only two hours of sleep before starting work and had turned his back to do administrative work as the plane headed down the runway, according to the National Transportation Safety Board. The FAA has since added a second controller.

Nearly a week after the crash, the first funerals began for the crash's victims.

Clark and Bobbie Sue Benton had boarded Flight 5191 for a trip to the Caribbean and vacation. They were buried Friday near Stanford in south-central Kentucky.

"We're asking difficult questions," the Rev. Wayne Galloway said at their funeral, attended by more than 300 people at Calvary Hill Baptist Church. "Why? Why do bad things happen to good people."

Another memorial service was planned Friday in Lexington for Larry Turner, who oversaw the University of Kentucky's extension service.