What is considered the best way to locate a submarine?

Locating a submarine effectively is a complex task, and using another submarine is often considered the best method for several reasons. Submarines are designed to operate stealthily underwater, which makes them challenging to detect using conventional surface ships or aerial surveillance. Another submarine, however, can utilize advanced sonar technology and tactics to detect other submarines in the vicinity.

Submarines can navigate at various depths and follow the target closely, utilizing passive sonar systems to listen for sounds of the enemy submarine without giving away their own position. This stealth advantage, combined with the sophisticated technology in modern submarines, makes them particularly adept at anti-submarine warfare operations.

Other methods like surface ships or aerial surveillance rely on different technologies, such as radar, sonar buoys, and other detection systems, but these can be less effective due to the underwater environment's noise and obstructions. While satellite technology can monitor surface activities and detect submarines at periscope depth, its capability to locate submarines operating deep underwater is limited. Thus, using another submarine presents the highest likelihood of detecting and tracking an adversary's underwater craft.