USA (11 Jan 2006) -- If you are scuba diving, be sure not to swim anywhere near any ship or installation that has been protected by the Raytheon Corporation's new "swimmer denial" system. Otherwise you will very quickly feel extremely sick and probably drown. Raytheon's underwater sensors detect any unwelcome presence and trigger an underwater sound system that emits extremely powerful pulses of low frequency audio. The pulse rate and audio frequency are chosen to make human organs resonate like organ pipes, causing divers to vomit into their masks or suffer internal ruptures. The idea of blasting very powerful sound at underwater targets is not new. It can even be used to detonate incoming torpedoes. But it can also cause havoc with marine life. | | Raytheon's new system is "greener" because the main sound projector, in the middle of the secure zone, emits sounds with power and frequency that are relatively safe. A dozen or so secondary projectors in a ring round the zone also emit safe pulses. But in the region near each secondary projector the main and secondaries combine to produce a sound which is decidedly dangerous. Would-be spies or terrorists cannot get through the ring but there is no widespread danger to fish, dolphins or whales. SOURCE - New Scientist |
