What Really Happens Inside a Submarine During Deep Dive

Added: 2026-05-16

[00:00:00]When a submarine begins a deep dive, it does not simply sink into the ocean. An entire chain of systems starts working together instantly.

[00:00:10]The first thing that happens is the ballast tanks begin filling with seawater.

[00:00:14]As the submarine becomes heavier, it slowly loses buoyancy and starts descending beneath the surface.

[00:00:21]But, going deeper creates a huge problem. Pressure.

[00:00:26]Every few meters underwater, the force pushing against the submarine increases dramatically. During deep dives, the hull can experience thousands of tons of external pressure trying to crush the vessel inward.

[00:00:38]Inside, crews constantly monitor depth, oxygen, pressure systems, and hull integrity.

[00:00:45]And surprisingly, the submarine does not dive straight down.

[00:00:49]Small control fins adjust constantly to guide the vessel smoothly through the water, almost like an underwater aircraft. As the submarine reaches extreme depths, the metal hull can even begin making cracking and popping sounds from the pressure outside.

[00:01:07]But, the most impressive part is this.

[00:01:10]Even deep underwater, hidden in darkness and pressure, the submarine remains carefully balanced between sinking and floating.

[00:01:19]One small mistake and the ocean takes control immediately.