Reza Najafi - Associate Professor, Islamic Azad University, Tonekabon, Iran

In countries near the ocean; sea; Lake; and marinefood and commercial resources are of greatimportance; At sea and on the coast and on land,the defense of national resources comes firstTherefore, in order to preserve these resources, ithas defended its maritime borders by using thenavy, air force and submarine.Separate ships with all the necessary weapons -even building ships on which it is impossible toknow and where helicopters and jets can movesafely. And to hide from the eyes of ships and theAir Force, they also built small, large submarineswith the most dangerous torpedoes, which are themost important defense weapon of success, andover time, scientists have been able to find thesesubmarines using sound and heat radars;Determine where the submarines are hiding, as wellas to prove the torpedoes faster; Using othersubmarines that could descend to great depthsagainst enemy submarines, which made it difficultfor flying fighter jets to fire bullets at submarines,and vice versa for submarines to fire aircraft. Andit made war jets and even hitting enemy ships hard.Because until the submarine came up to attack withair weapons (out of water) under the bullets of theenemy - every day countries have been looking forstronger weapons and more guaranteed defense,and of the highest financial importance for theircountry's capital.