Not so fast the russians have used rubber propellors on thier Bravo class target submarines but that was because they fired dud torpedos and had them bounce off the hull so if the torpedo did come up the rear there was little chance that the torpedo would fracture or smash apart the metal screw simply because rubber bends.

The caterpillar in the book were prop sets inside the hull while in the movie, the caterpillar was something like an ionengine. Don't laugh, it's possible by physics and there are test ships in the world with such an engine. The most known should be the japanese "Yamato". The drawback of this enginetype is, that it needs saltwater, up to 75% loss in brack and almost no power in sweet.
It ionises the salt in the water and creates enough push to move the ship.

(edited to censor myself - it's no different than a propeller)