I can speak about lightning with some authority... Two strikes about 10 years apart... I am a ham operator with big antenna towers and reasonably knowledgeable about lightning protection (I lecture to ham clubs on the subject at times)... Last summer my daughter and her husband had their two year old, 36' boat - with an electronics suite to die for - subject to a strike... The voltage surge got onto the dock wiring plus passing through the water to the zincs, wiping out their boat... Engines would not crank or run along with the pumps, radar, gps, radios, plotters, autopilot, TV, frig, etc., everything dead... I told Mike and Luan that they should insist on all electronics and electrical equipment being replaced not just repaired... Of course, the insurance company wanted to repair only... They took my advice and stood firm... After the gear had been repaired (that which could be, not all was revived) per my advice he insisted they keep it on the test bench and have the power cycled on and off multiple times a day to prove it was reliable... After a week of repeated power cycling things began failing... This would have been the rough equivalent of an entire boating season of power cycles so had they accepted the repairs then next year they would have begun having repeated failures, for which the insurance company would deny liability... Finally the underwriter saw the light as he kept getting additional bills for labor and parts and agreed to new equipment... The bottom line is that the only gear that will likely survive is not connected to either the electrical supply OR the ground system... Any connection will allow voltage to build up on the equipment and then jump to something near by... Remember, the strike has jumped from miles overhead to the ground and will have up to 300,000,000 volts with currents up to 100,000 amperes... ANY cable connection to the equipment, including the ground, will allow a charge to build up - it doesn't require a complete circuit, the lightning will complete the circuit by arcing over to something... The problem you will run into is that production boats are not arranged to make the equipment easy to completely unplug the antenna, power, computer, and ground connections... My boat currently building will be configured to allow this... Now,, back up radios, etc., do not have to be in a Faraday cage (metal box) just completely disconnected.... The strike I had, all gear was unplugged (except for the ground cables! )... The antenna rotator wires took the charge then jumped from the rotator control box sitting on a shelf above the radios, down about 8" to the supposedly safe top radio in the stack, then jumped from one radio to the next... The only radio that survived happened to be unplugged from the radio stack and was laying on the bench totally disconnected, but mere inches from the other radios that were destroyed - destroyed because they were still connected to the ground system... denny --------------------------------- The fish are biting. Get more visitors on your site using Yahoo! Search Marketing.