By Eric Beech
WASHINGTON, March 11 (Reuters) - Deborah Hersman, who headed the U.S. National Transportation Safety Board during high-profile investigations into plane crashes and other transit mishaps, said on Tuesday she would leave the agency in April after almost 10 years.
Hersman's surprise departure comes as the NTSB is gearing up to help with the investigation into the missing Malaysian Airlines flight MH370, which disappeared on Saturday about an hour after it took off from Kuala Lumpur with 239 passengers and crew.
The U.S. agency dispatched a team of investigators to Malaysia this week, and is likely to be among the investigators analyzing the aircraft's black box, if the flight recorder is located.
The NTSB took the lead on two of the biggest aviation investigations in 2013: the battery fire problems that grounded Boeing Co's 787 Dreamliner aircraft for several weeks early in the year, and the crash of an Asiana Airlines Inc jet at San Francisco International Airport in July.
Hersman, 43, often traveled with NTSB investigative teams to the site of major accidents and was the agency's public face at briefings and news conferences.
"I look back at the hundreds of investigations and recommendations that have been issued during my tenure at the NTSB and I have seen the landscape of transportation safety improve before my eyes," Hersman said in a blog post.
Hersman will become president and chief executive officer of the National Safety Council, a safety advocacy group based in Itasca, Illinois, the group said in a statement.
Hersman was named a board member of the NTSB, an independent federal agency with about 400 employees, in 2004 by President George W. Bush and was appointed chairwoman in 2009 by President Barack Obama.
Among the non-aviation investigations led by Hersman have been those involving a commuter train derailment in the Bronx, New York, in December 2013 that killed four, and a collision between a tanker and a container ship in the Houston Ship Channel in 2011.
Hersman's "reassuring confidence has helped lead this country through some of our most difficult recent transportation accidents," said Senator Jay Rockefeller, a Democrat from West Virginia, where she was raised.
"I always trusted that Debbie would put the full weight of the NTSB behind any investigation, and she would be tireless in working to uncover the facts," Rockefeller said.
Hersman worked for the Senate Commerce Committee, chaired by Rockefeller, for five years before joining the NTSB.
Campaigning against distracted, drunken and fatigued driving was among her signature issues.
The NTSB raised the ire of automakers in 2011 by calling for a ban on the non-emergency use of portable electronic devices for all drivers. "Distraction, whether it's hands-free or handheld, whether it's texting or talking, is deadly," Hersman wrote at the time.
"She was the first in the federal government to restrict the people at the NTSB from being on the phone when the car was moving," said Mark Rosenker, who chaired the agency from 2006 to 2008.
Christopher Hart, NTSB's vice chairman, will take over as acting chairman when Hersman leaves on April 25.
Hart, an attorney and licensed pilot, has a long career in transportation safety that includes a stint as deputy director for air traffic safety oversight at the Federal Aviation Administration.
The National Safety Council is a non-profit organization chartered by Congress. It seeks to use education and research to prevent accidental injury and death from incidents ranging from distracted driving to workplace safety to prescription drug overdoses.