McCaskill's argument that allowing iPads into the cockpit means they should be allowed in the cabin seems weak to me, for two reasons. First, if there are inst

McCaskill's argument that allowing iPads into the cockpit means they should be allowed in the cabin seems weak to me, for two reasons. First, if there are instrument malfunctions in the cockpit, the crew can turn off their own wireless devices to see if they were interfering. It's much harder to get 300 people to shut off their devices in a hurry, especially when some have tucked their devices in the seatback pocket and gone to sleep. Second, it seems entire plausible to my (non-electrical-engineer) mind that 300 devices of a large variety of makes are more likely to cause interference than just one or two, both for the combined signal and the chance that one will be badly designed. I used to be indignant about the PED rule as well. After reading a number of online discussions on it, I'm not convinced that it's obvious that they should be allowed.