A Comair commuter jet took off from a short runway used by private aircraft rather than a longer one typically used by commercial jets before it crashed Sunday morning, a National Transportation Safety Board official said. Comair Flight 5191 crashed about half a mile past the end of the runway shortly after takeoff Sunday morning, killing 49 of the 50 people on board. The sole survivor, first officer James Polehinke, was in critical condition at a Lexington hospital. The Delta commuter flight had been cleared to take off from the 7,000-foot Runway 22 at Lexington's Blue Grass Airport, sources told CNN earlier Sunday. Instead, evidence at the scene indicates the plane took off from Runway 26, which is about half as long, NTSB member Debbie Hersman told reporters Sunday evening. "We're still working on determining what was going on in the cockpit, what information was discussed between air traffic controllers and the pilots," Hersman said. "That's part of our investigation, and we hope to have more information about that later."