Quote:
Originally Posted by teh603
I was referring to Faraday-ing the passenger compartment, instead of the cockpit. Guess I wasn't quite clear enough.
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I understood what you said. I was trying to explain how jet aircraft are laid out. The "passenger compartment" is not the discrete place you seem to think it is. As I said in my post, there are electrical links between the cockpit and cabins -- that's how you hear the pilots' announcements and that's how the pilots turn the seat belt signs on and off. And you obviously can't Faraday the cockpit. Wires and hydraulics run through the sides, ceiling, and floor of the cabins. There are sensors in the main doors and emergency overwing doors that have to be readable in the cockpit. There are fire sensors all over the plane, too -- inflight fire is very dangerous. The pilots need to be able to monitor places like the lavs and galleys for it. The plane's electric power supply runs off an engine bleed air turbine while the engines are running, off the APU when they are not, and that power has to be distributed throughout the plane, including to locations like the galleys, your reading light and the lav flush vacuum pumps. Any flow of electricity creates an electromagnetic field that can interact with other fields from devices, magnets, etc.
You might be able to design individual Faraday cages that could be worn in your seat but you can't isolate the passenger cabins from the rest of the aircraft's electrical supply and electronic sensor equipment.
As for the fact that planes fly past radars etc., yeah, but not that close (EMF decreases as a function of the square of the distance from the source). Planes are designed to use radar but transmissions are shielded from other components -- same with radio transmissions. Plane engineers design systems to avoid interference with one another, but they don't have crystal balls to know where pax may sit with an ever increasing number of electronic devices with bigger and bigger capacity batteries emitting stronger and stronger signals.