When The Hunt for Red October came out in 1984, and with it the invention of the techno-thriller genre (author Tom Clancy's claim to literary greatness), one of the stars was a modified Typhoon-class nuclear-powered ballistic missile submarine (SSBN). That novel, of course, was adapted to film in 1990.
The book and the film featured two different versions of the silent drive. The book used impellors, while the film used magneto-hydrodynamic propulsion. Now, something that is somewhat similar to the latter version of the Red October's silent drive could be a reality… thanks to the People's Liberation Army Navy.
A 1993 photo of a Chinese Han-class submarine. These vessels were very noisy, and thus, easy to track. Newer Chinese submarines could have a very quiet permanent magnet motor. (US Navy photo)
According to a report by Popular Mechanics, the Chinese have tested a drive using a "permanent magnet motor" near Hainan Island. A release by the Chinese military noted that China was also experimenting with a "shaftless" pumpjet propulsion system.
Permanent magnet motors run much more quietly than conventional types currently in use on submarines. This is due to their "brushless" nature, which also means they can be smaller, taking up less volume on submarines (which are notoriously cramped) and increasing their reliability and also improving their endurance.
USS Dallas (SSN 700) conducting training operations in 2000. This vessel was another star in the book and film versions of The Hunt for Red October. (U.S. Navy Photo by Journalist 1st Class Jason E. Miller)
According to GlobalSecurity.org, China has a small number of nuclear submarines at present, roughly a half-dozen attack subs and four ballistic missile submarines. While greatly outnumbered by those of the United States, China is planning to build many more nuclear-powered subs by 2030, including versions more modern than the Shang and Jin classes that are their current state of the art.
The United States is not standing still. Reportedly, the new Columbia-class SSBNs will also be using a magnetic-drive technology. That said, it should be noted that in both the book and movie versions of Hunt for Red October, the United States Navy was able to track the titular submarine.