Friday, 28 October 2011


Not only is it an early take on the Hunt for Red October's caterpillar drive, but they've even have DIY instructions for building your own.

Nuclear submarine not included.


Cthel said...

Well, the film version anyway; the original book version was a set of ducted propellers.

Is there any mention of how to build the superconductors the system needs for any sort of reasonable performance? I can't quite read the text.

David said...

Follow the link for a readable version

Cthel said...

Ah, thanks.

Not a bad little demonstration set up - unfortunately, getting hold of a suitable transformer could be a little tricky in these days of switched-mode power supplies.

eon said...

The Canadian UFO "documentary" "UFOs Are Real", directed by Ed Hunt (who later wrote and directed "Starship Invasions" with Robert Vaughn and Christopher Lee), includes footage of a radio-control electromagnetic-drive submarine built by the USC engineering department in 1965. It had its MHD "pusher" coils on the outside; the drive principle (Fleming's Left-Hand Rule) works a bit better that way, as you don't get the harmonic-wave "surge" as you do in an enclosed duct.

An actual "caterpillar" or "tunnel" drive would most likely have to use a combination of impeller turbines and MHD coils. The turbines would provide the main thrust, and the coils would act as flow-regulators to eliminate, or at least reduce, the "choking" effect of trying to ram an incompressible mass (water) down a pipe at high flow rates.

Its use as a high-speed drive system is questionable, due to the power curve. Forget fission; for high speed, you'd need a fusion plant to crank out enough horsepower. This means that even with a Westinghouse S7W, the most likely home for this would be a boomer, which is more about "quiet" than "screamingly fast".

Detectability by ASW assets would be interesting. Clancy was correct in stating that most of the impeller-generated flow noise would get lost in the drive tunnels. However, a harmonic as depicted in the film would be a likely signature detectable on passive sonar. In short, a third-flight 688, Seawolf, or Virginia would hear you all too well.

A more serious drawback is that the MHD elements would give your "silent drive" boomer an EM footprint the size of Chicago on MAD. Which ASW chopper pilots just absolutely love to drop Mk 46s on.