Microwave-goodbye weapon: 'Heat ray' crowd dispersal cannon unveiled (VIDEO)

12 Mar, 2012 11:47 / Updated 13 years ago

The American military have presented the world with a new weapon, informally named the heat ray or microwave cannon. The “Active Denial System” is a non-lethal weapon primarily designed for crowd control.

A video was uploaded on YouTube by USFORCESTV channel of the US military testing a new super high frequency (SHF) weapon. Rumors have long been spread about a “cannon”, which can be mounted on a military vehicle to disperse crowds with the help of a high-powered beam of electromagnetic radiation. Hearsay still causes the US Department of Defense deny it has spent $120 million on a mobile microwave oven.The Active Denial System (ADS) beams a high-frequency, man-sized electromagnetic wave 1,000 meters.

ADS fires a high-powered beam of high-frequency millimeter waves at 95 GHz (a wavelength of 3.2 mm). Similar to the same way that a microwave oven heats food at 2.45GHz, the millimeter waves excite the water and fat molecules in the body, instantly heating them via dielectric heating and causing intense pain. While microwaves will penetrate into human tissue about 17mm (0.67"), the millimeter waves used in ADS only penetrate the top layers of skin, with most of the energy being absorbed within 0.4 mm (1/64").

A person affected by ADS feels a sudden blast of heat that many compare to opening a very hot oven. The target feels pain and reflexively steps or runs away. During the presentation US servicemen managed to immediately disperse a group of disguised marines who played the role of an aggressive crowd. The US military say this weapon’s injury risk is far lower than other weapons like rubber bullets or pepper spray. The ray does not cause cancer or exacerbate existing cancer, nor does it causes fertility problems or birth defects. That is according to Stephanie Miller, with the biological effects branch of the Air Force Research Laboratory as quoted by Stars and Stripes web edition. She also said the weapon has been tested on more than 11,000 people, and in just two of those cases, it caused second-degree burns. Experts believe the idea appeared in the mid 1990s during a US campaign in Somalia, where American soldiers were often attacked by local population only armed with stones or sticks. Some kind of weapon was needed to avoid victims among civilians and to protect soldiers at the same time. The properties of an electro-magnetic field have been long used to put the enemy’s electronic instruments out of order. The prototypes of a microwave novelty were first used almost 30 years ago and have significantly diminished in size since then: the first version reached the size of a train carriage. Now it can be put on a Hummer. It is reported the Pentagon is about to create an airborne version of the heat ray.