on 1 April 1981 Balao-class submarine USS Bowfin SS-287 became a museum ship in Pearl Harbor, HI.MuseumShip at USS Bowfin Submarine Museum & Park, Honolulu, HI
On 1 April 1990, Hawaiian Chieftain starts her maiden voyage to French Polynesia, arriving in Papeete on April 20.
on 1 April 1994 Project 641 (Foxtrot-class) diesel-electric attack submarine Foxtrot B-39 was decommissioned.
on 1 April 1943 Gato-class submarine USS Croaker SS-246 was laid down at Electric Boat Co.. Groton, CT.MuseumShip at Buffalo and Erie County Naval and Military Park, Buffalo, NY
On 1 April 1988, T-47-class destroyer Maillé-Brézé D-627 was decommissioned.MuseumShip Maillé-Brézé, Nantes, France
On 1 April 1915 M29-class monitor HMS M33 was laid down at Workman Clark for Harland and Wolff.MuseumShip at the National Museum of the Royal Navy, Portsmouth, UK
On 1 April 2005, Gearing-class destroyer ROCS Te Yang (DDG-925) was decommissioned at Kaohsiung, Taiwan.She is the former USS Sarsfield (DD-837), and is now a MuseumShip in Tainan City.