Imagine low-cost nuclear-powered torpedoes that could travel virtually undetected across the Pacific Ocean and hit US targets. For a group of researchers in Beijing, it’s not just a dream, it’s a concept they believe they can make into reality.

Chinese researchers claim to have completed the conceptual design of such a weapon system. The torpedo system will use a disposable nuclear reactor to achieve and maintain a cruise speed of over 30 knots (35 mph) for 200 hours before launching the reactor. The torpedo will then continue to draw power from the battery to launch the planned attack.

The Chinese weapon proposed by Guo and his group has a conventional warhead (though a nuclear warhead may be possible), is small enough to fit in a conventional torpedo tube, and can be produced in very large quantities.

“Due to its high flexibility and low cost, this unmanned underwater vehicle equipped with a nuclear power system can be used as a nuclear attack submarine instead of a nuclear missile,” said the engineer.

The weapon will meet China’s growing demand for “small, high-speed, long-range unmanned underwater vehicles that can be used for reconnaissance, surveillance, assault and strategic strike missions.”

The key to the system is an inexpensive, disposable nuclear reactor that releases enough energy to propel the torpedo long distances before disabling the torpedo before the system’s final attack.

“We need to think outside the box to build a new nuclear power system with mature and simple technology, easy to use and maintain, inexpensive and suitable for mass production,” Guo said. Guo’s team “removed most of the shielding materials from the reactor and shielded only a few critical components from radiation.”

They also “replaced the expensive rare earth coatings inside the reactor core with inexpensive materials like graphite.” The resulting reactor will generate “more than 1.4 megawatts of heat from less than 8.8 pounds of low-uranium fuel.”

The reactor will be of such a cheap design that only 6% of the heat generated will be converted into electricity to power the torpedo, but that’s more than enough for a one-way flight.

According to the new torpedo design, the chain reaction will not start approximately half an hour after the torpedo leaves the launch pad. This makes it safe to use as it will not be radioactive until it reaches a safe distance from the platform from which it is launched.

This chain reaction would occur about 20 times faster than a conventional nuclear submarine reactor to reach an operating temperature of about 600 degrees Fahrenheit. This will accelerate the torpedo to a cruising speed of about 37 miles per hour.

According to the researchers, the reactor “can operate for up to 400 hours, covering a distance of more than 6,200 miles – roughly the distance from Shanghai to San Francisco.”

The developers said it would then detach from the torpedo and fall to the seafloor, activating a safety mechanism to stop the remaining chain reaction. “Even if the hull breaks, the embankment and the entire hull fall into the wet sand on the seafloor, there will be no critical accident in the reactor. Safety is assured.”

The weapon will be designed to be fired from any platform, particularly China’s growing submarine fleet.