National Transportation Safety (NTSB) Board Member Robert L. Sumwalt will again serve as the agency’s vice chairman following his designation as vice chairman by President Donald Trump.

The designation of vice chairman was made in conjunction with the President’s intent to nominate Sumwalt for another five-year term as a board member.

Sumwalt officially assumed the duties of vice chairman Friday as the term of the agency’s current Vice Chairman, Bella Dinh-Zarr, concluded Wednesday. Dinh-Zarr, who served as the agency’s acting chairman since March 16, will remain at the NTSB, applying her transportation safety expertise in the capacity of a board member.

“I am honored to have the opportunity to serve our nation as the NTSB’s vice chairman,” said Sumwalt. “I want to thank Christopher Hart for his leadership during his tenure as the NTSB chairman, and Bella Dinh-Zarr for her outstanding work as vice chairman and most recently as acting chairman. Together, they have helped advance transportation safety, making us all safer, while also making NTSB one of the best places to work in government.”

The NTSB has five board members, each nominated by the president and confirmed by the Senate to serve five-year terms. By statute, the president designates, with Senate confirmation, a chairman and also designates a board member as vice chairman. The vice chairman and chairman each serve two-year terms. When there is no designated chairman, the vice chairman serves as acting chairman. Board members whose terms expire may remain on the board until their replacement is appointed.

Sumwalt began his tenure with the agency in August 2006 when he was appointed as the 37th member of the NTSB, whereupon President George W. Bush designated him as vice chairman for a two-year term. President Barack Obama reappointed Sumwalt to an additional five-year term as a board member in November 2011.