In 1942, shortly after the U.S. entered World War II, Chesapeake was given light armament, painted battleship gray and moved to Sandwich, Massachusetts to serve as an Examination Vessel. After the war, she returned to the Chesapeake station. She ended her service at the Delaware Bay station in 1970.
After retirement, she was transferred to the National Park Service, and began a new career as a seagoing environmental center in Washington, D.C. In 1981, as Chesapeake, she joined the Baltimore Maritime Museum's collection of historic ships.
Lightship 116 is a National Historic Landmark