Nevertheless, Les Dorr, a spokesman for the F.A.A., said the agency would rather err on the side of caution when it comes to digital devices on planes. He cited a 2006 study by the Radio Technical Commission for Aeronautics, a nonprofit group that tests and reports on technical travel and communications issues. The group was asked by the F.A.A. to test the effects of cellphones, Wi-Fi and portable electronic devices on planes.

Its finding? “Insufficient information to support changing the policies,” Mr. Dorr said. “There was no evidence saying these devices can’t interfere with a plane, and there was no evidence saying that they can.” I’m not arguing that passengers should be allowed to make phone calls while the plane zooms up into the sky. But, why can’t I read my Kindle or iPad during takeoff and landing? E-readers and cellphones can be easily put into “Airplane Mode” which disables the device’s radio signals.

Fliers Still Must Turn Off Devices, but It’s Not Clear Why – So if you want to “err on the side of caution,” and you know what we all know — as Bilton mentions, there are millions of passengers each year who simply ignore the command — why not ban all electronic devices from planes? Confiscate them at boarding and return them at the end of the flight? That the FAA doesn’t do this shows as clearly as anything that they know there is no danger and that their regulations are therefore utterly pointless.