Operation Z (1944)

Operation Z[nb 1] was a defensive plan put into place by the Japanese during World War II to defend the Marianas Islands, and in particular, Saipan.

[1] With the impending invasion of the Marianas Islands, Admiral Mineichi Koga, on March 8,[3] sponsored Operation Z, as a defense against the American attack.

This plan was approved by the Imperial Japanese Navy General Staff, with a formal title of Combined Fleet Secret Operations Order No.

[4] Throughout the spring of 1944, the aircraft losses for the Japanese continued to mount which was severely endangering the success of the operation; however the death knell occurred on March 31, 1944, when Mineichi Koga and some of his staff were killed in two separate plane crashes,[1] while the remainder were captured.

Traveling mostly on the surface for speed, and diving only when needed, the submarine survived depth charging twice, arriving near the American naval base in Darwin, Australia on May 19.