This Day in Naval History – May 21
1850 - Washington Navy Yard begins work on first castings for the Dahlgren guns
1917 - USS Ericsson (ERIXF) fires first torpedo of war
1944 - During preparations for the invasion of Saipan an accidental ordnance blast on LST 353 sets off cataclysmic ammunition explosions at West Loch, Pearl Harbor, killing 163 and injuring 396. Six tank landing ships (LST-39, LST-43, LST-69, LST-179, LST-353, LST-480), three tank landing craft (LCT-961, LCT-963, LCT-983), and 17 track landing vehicles (LVTs) are destroyed in explosions and fires.
1964 - The initiation of the standing carrier presence at Yankee Station in the South China Sea.
(Source: Navy News Service)