Whooshing sound of a submarine propeller

As the audio starts, the audience is immediately immersed in the deep-sea world, with a compelling whooshing sound echoing through the environment. This is the powerful sound of a submarine propeller slicing through the vast ocean depths. The sound is not harsh or grating; rather, it's a rhythmic, pulsating whoosh, like a giant heart beating in the abyss. The propeller's noise is consistent, a testament to the marvel of human engineering that allows massive structures to glide effortlessly underwater. The audio is synthetic, yet it perfectly mimics the real-life sounds. It's as if one is inside the submarine, feeling the vibrations and the hum of the propeller. There's an undercurrent of excitement in the sound, a suggestion of exploring the unknown and venturing into the mysterious deep blue. The sound is not just from the propeller alone. Subtle hints of the sub's mechanisms, the creaking metal, the hum of the engine, are interw