The US Homeland Security is worried about Hydrofoil or Skimmer Craft used as fast moving bombs on water entering one of our ports or Naval shipyards. If you will remember the XXX Movie with the Hydrofoil Craft with a Biological Weapon which would kill millions of people if it released its gaseous cargo.

http://www.hollywoodjesus.com/movie/xxx/27.jpeg

http://www.hollywoodjesus.com/xxx_photo.htm

Although this is hypothetical it is also very possible. One study described our many inlets and rivers such as he Chesapeake, Potomac, San Francisco Bay, Columbia River, Puget Sound, Hudson, Port Houston Ship Lane, Boston Harbor or Tampa Bay.

Luckily for us we have great tracking, radar and competent US Navy and US Coast Guard. However what if one was launched from a Cargo Ship outside of US Territory in international waters? Then what, how do you stop something moving that fast or respond to the threat? Some of these high tech versions travel at nearly 100 knots. A ten thousand pound payload, which is what the nuclear bombs weighed that were dropped on Japan in WWII, could easily be carried by a hydrofoil that was 30 feet long.

The hypothetical of the XXX movie is questionable because the biological gas would be quickly diluted with the relative wind in such coastal areas from off shore or onshore breeze. But a hydrofoil Unmanned Autonomous Device would render very serious consequences. Obviously a good point for trying to prevent rogue nations from developing Nuclear Weapons, which could end up in the hands of International Terrorists piloting hydrofoils, who do not care if they blow up with the Weapon of Mass Destruction.

Once the bomb gets within 1 mile of the shore or enters a harbor there are no longer any possible good outcomes, once it touches land there are only disastrous scenarios. When people run the scenarios and animation programs and study these things, the findings are extremely alarming.

http://www.tybeetyme.com/tb/images/bomb_blast_map.gif

http://www.parowanprophet.com/maps/mohawk_350_KT_nuke.jpg

We should not assume that simply because we board every cargo ship from certain countries that we are safe, these things could come on any type of ship or ultra large yacht. And the technology is well known, used in sport marine, luxury marine, military worldwide. How can you stop a hydrofoil traveling at 100 knots from entering a harbor?

One way is to have large high-pressure tanks under water at the mouth of the river or harbor. Similar to giant cylinder propane tanks only the width of the mouth of the inlet, if you fail to hit the hydrofoil with conventional defense weapons, you release all the gas as the hydrofoil enters the harbor. The tanks can be pipelines which are in use, with quick release valves opening upward, the can be closed off tanks with CO2, Oxygen, Hydrogen, methane or other such gas. The gas as it escapes creates a cavity and the hydrofoil or skimmer craft falls as it would over a waterfall tumbling downward. Then the water fills in over it and even if the weapon of mass destruction goes off, it does so underwater which provides one more layer of protection. This is a last resort defense mechanism able to high-speed boats, skimmer craft, hydrofoils and medium sized fast moving ships. Of course this is only one possible way to stop such attacks as we also have missiles, guns, cannons, etc. at the military shipyards, harbors and inlets.