Hersman, 43, has been chairman of the accident investigation agency since July 2009. The NTSB is coping with its busiest stretch since the 1990s.
Her profile has been raised this year as the public face of the board's investigations into what caused a battery to catch fire on the Boeing 787 Dreamliner, and the July 6 crash in San Francisco of Asiana Airlines Flight 214, the first fatal passenger airline accident in the United States in four years.
"I am grateful for the faith that President Obama has placed in me and look forward to working with my fellow board members to make transportation - across all modes - safer for our citizens," Hersman said in an e-mailed statement.
The safety board chairman, who must be confirmed by the Senate, helps guide probes, hold hearings and recommend safety improvements, without authority to implement them.
Obama separately signed an order making Hersman the acting vice chairman, which doesn't require Senate approval, said Kelly Nantel, the agency's spokeswoman, in an interview.
That allows Hersman to continue running the agency if the Senate doesn't approve the nomination before Hersman's current term ends. The Senate is scheduled to go on recess for five weeks starting Thursday.
Christopher Hart, who has been the vice chairman, was also renominated by Obama Thursday to remain on the board.
Hersman's name was mentioned earlier this year as a possible successor to Ray LaHood as Obama's transportation secretary by Sen. Jay Rockefeller of West Virginia, one of Congress' most senior Democrats. Obama instead chose Anthony Foxx, who was mayor of Charlotte, N.C.
A former staff member on the Senate Commerce Committee that Rockefeller now heads, Hersman was appointed to the safety board in 2004 by President George W. Bush.