Navy Day is celebrated in India on December 4 to invoke the memory of the launch of Operation Trident during the Indo-Pak war on 1971, and as a mark of reverence to those who were martyred in the war.Navy Day is celebrated in India on December 4 to invoke the memory of the launch of Operation Trident during the Indo-Pak war on 1971, and as a mark of reverence to those who were martyred in the war.