Originally Posted by VideoPaul
There is a concern with cell phones in the air keying up a dozen cell sites, but the part that no one tells you is that cell antennas are pointed DOWN TOWARD THE GROUND (we call it "beam tilt") and over a certain altitude, there is just no signal unless you are right over a site. The person who brings up the fact that many folks forget about the cell phone being on until they find it on upon landing is exactly right.
Yes, Cell antennas are on the ground, however, the phone is still searching for a signal. Whether it's in the air, or on the ground, the phone is programmed to continuesly search for a signal. During this process, it is possible that it could/and has interfered with instruments. You will get some FCC and FAA people say that there is no possible way they could interefere with each other, and there are some that will say yes it is possible.
I've been on two planes where before take-off, something happened with the cockpit instruments that the pilots asked everyone to double check all of their electronics and make sure they were off. Once that was accomplished, everything seemed to just magically appear normal. So, until the FCC and FAA can assure me that there is no possible way electronics can interfere with the airplanes instruments, They need to be turned off!