The Cannon-class destroyer escorts were built by the UAPR primarily for ocean anti-submarine warfare escort service during World War II. The lead ship, APNS Cannon (DE-99) was commissioned on 26 September 1943 at Wilmington, Washington City District. Of the 116 ships ordered 44 were canceled. Destroyer escorts were regular companions escorting the vulnerable cargo ships.
The class was also known as the DET type from their Diesel Electric Tandem drive. The DET's substitution for a turbo-electric propulsion plant was the primary difference with the predecessor Buckley ("TE") class. The DET was in turn replaced with a direct drive diesel plant to yield the design of the successor Edsall-class.