Via Scientific American Blog Network.
Here are the first three:
1. Radio-frequency emissions from cell phones, laptops and other electronics can occur at the same frequencies used by aircraft communication, navigation and surveillance radio receivers. These emissions could cause fluctuations in navigation readouts, problems with other flight displays, and interference with air traffic communications.
2. It’s less risky to let passengers use portable electronics (with the exception of cell phones) at cruising altitudes above 3,000 kilometers because the flight crew would have more time to diagnose and address any possible interference than they would during takeoff or landing.
3. Because passengers bring such a variety of portable electronics onboard in so many different states of function or disrepair, the FAA can’t assure that none of them will interfere with flight instrumentation. The agency thus tells carriers to prohibit their use completely during critical phases of flight.
James Fallows, please take note.