National Transportation Safety Board (NTSB) Chairman Deborah A.P. Hersman filled two key senior management positions, naming Dr. David L. Mayer managing director and Nancy Lewis director of government affairs.

Dr. Mayer, who has been deputy managing director since January 2005, began his career at the NTSB in 1991 in the office of research and engineering, where he was responsible for transportation safety databases and the design and management of safety studies. In 1996 he moved to the office of aviation safety and also served as deputy chief and acting chief of the human performance division before moving to the managing director's office in 2001.

Meanwhile, Lewis will be responsible for maintaining the agency's relationship with the U.S. Congress and agencies of the federal government. Lewis came to the NTSB in April 2005 as the special assistant to then board member Hersman.

Before joining the NTSB, she worked in the office of general counsel for the Transportation Security Administration and for 13 years before that in the office of chief counsel at the Federal Railroad Administration (FRA). She was also detailed for a year by FRA to the Senate Committee on Commerce, Science and Transportation.