On 21 September 1944, LCI(L)-351-class large landing craft USS LCI(L)-1091 was commissioned with LTjg. Henry S. Allen Jr. in command
MuseumShip Blog
On 21 September 1973, Gearing-class destroyer USS Eversole DD-789 was struck from the Naval Vessel Register. She was transferred to Tukey on 11 July 1973 as TCG Gayret (D-352), an is now a museum ship in Izmit, Turkey.
On 21 September 1945, Motor Torpedo Boat PT-617 was completed at Electric Boat Co., Bayonne, NJ. The boat was assigned to MTB Squadron 42 and slated for service with the Pacific Fleet, but this was later cancelled.
On 20 September 1969, Lütjens-class guided-missile destroyer FGS Mölders (D186) was commissioned, Kapitän zur See Günther Fromm commanding.
MuseumShip at Deutsches Marinemuseum, Wilhelmshaven, Germany
On 20 September 1967, Cunard's QE2 was launched at John Brown and Company, Clydebank, Scotland, christened by Queen Elizabeth II
Museum
The QE2 Dubai, United Arab Emirates

