On 20 May 1965 Peder Skram-class frigate HDMS Peder Skram (F352) was launched at Helsingør Skibsværft, Helsingør Denmark
On 20 May 1950 Tang-class submarine USS Gudgeon (SS-567) was laid down at Portsmouth Naval Shipyard. Leased (later sold) to Turkey on 30 September 1983 as TCG Hizireis (S342).Now a museum ship in Izmit, Turkey.
On 20 May 2009, Dutch yacht 'Onrust' was launched in the Mohawk river.MuseumShip (replica) at the Connecticut River Museum, Essex, CT
On 20 May 1942, River-class frigate HMS Fal was laid down at Smiths Dock Company, South Bank-on-Tees, UK.She was transferred to Burma on 25 May 1947 as UBS Mayu, and has been preserved as a museum ship at Myanmar Naval Training Headquarters
On 12 May 1942 South Dakota-class Battleship USS Massachusetts BB-59 was commissioned with Capt. Francis E.M. Whiting in command.MuseumShip USS Massachusetts BB59 at Battleship Cove, Fall River, MA