The USS Flagstaff (PGH-1) was the only gunboat of her class to be built. Laid down in June 1966 by aircraft manufacturer Grumman, she was commissioned into service in September 1968. As an experimental vessel, she had an operational evaluation period before being deployed to the conflict in Vietnam; she was used in high-speed patrol missions until 1970. She returned to the US at that point, being used in various readiness trials and serving as a testbed for many systems. Loaned several times to the US Coast Guard to evaluate the suitability of hydrofoil craft, she ultimately produced unsatisfactory results. Eventually, she was returned to the navy and sold for only $30,000.

She is a premium gift rank III American motor gunboat, introduced during Update "Alpha Strike" as a reward for the Battle Pass: Season XV, "Northern King". Being incredibly lightly armoured, she stands out as the fastest vessel in the US Naval tree, even faster than the USS Tucumcari found in the tech tree. This, of course, comes at the cost of even minimal protection, so captains can expect to use their mobility rather than protection to mitigate enemy fire. It also amusingly comes equipped with the turret of the M551 as its main armament, giving it a hard-hitting punch against enemy coastal vessels.