Did Missed Switch Bring Down Medical Flight?
The Detroit Free Press is reporting that the copilot of a Cessna Citation carrying an organ transplant team may have mistakenly turned on the aircraft's autopilot instead of its yaw damper, possibly leading to the crash of the aircraft in Lake Michigan off Milwaukee on June 4, 2007. Both pilots and the four members of the University of Michigan medical team were killed. The paper quotes a report from the NTSB's Recorded Radar and Airplane Performance Study Group, which did a computer simulation of the flight, as saying the results of the simulation are "consistent with the copilot inadvertently pushing the autopilot button instead of the yaw damper on the airplane center console." Shortly after takeoff, the cockpit voice recorder captured comments from the pilot that he was "fighting the controls" and blaming the problem on runaway trim. But the NTSB team says the results of the simulation "do not appear consistent with a pitch trim runaway."
The research team said that when they simulated runaway trim it didn't result in the rolling motions the pilot reported as he fought for control. According to the interim factual summary, the control problems started 18 seconds into the flight and the pilot is heard to say: "I'm fighting the controls. It wants to turn left hard" and "…she's rolling on me. Help me help me." The simulation report is one of many that will be taken into consideration when the board meets later this year to determine probable cause.