AB Class, 1913-1938
The U.S. Coast Guard’s AB Class vessels were known as Harbor Cutters, despite not meeting the modern Coast Guard’s definition for cutter. The smallest sized AB Class cutters were documented at 45 feet in 1918 and the largest were documented at 64 feet in 1923 (AB-19 and 20 Class).
Coast Guard history:
There isn’t much documented information about the AB Class Harbor Cutters. There is no known reference for exactly what the AB Class designation stands for. From what is known, early vessels used were built in 1913 and were former supply or cable boats that were purchased. It is safe to assume that these wood-hulled vessels were used to patrol harbors in a much different fashion than today, since shipping was still the major source of commerce transportation between continents.
Specifications for AB-19 and 20 Class cutters to be built for the Coast Guard were first documented in 1923. The specifications listed above are what we know about the size and make up of the vessel. By 1927, the AB’s (AB-24) length specification was listed at 52 feet with a 3’ draft and 34 ton displacement.
In between 1927 and 1935, the AB Class designation was changed from Harbor Cutter to Harbor Craft, the length was changed to 63’-6", and they were equipped with ice-breaking capabilities by the 1930s.
In 1934, AB Class Harbor Cutters were harbor craft operated by the Customs Service that were transferred to and operated by the Coast Guard. These vessels were made up of mostly ex-seized boats.
The exact year is not known when the Coast Guard decommissioned the AB-Class Harbor Craft vessels.
-PA3 Sebastian Warren, USCGR, 7 October 2000