Quoting FR Jones <seabeevet@...>:
Shooting from the hip on this, two issues come to mind. First, why wouldAs has already been pointed out here:
The core prohibition is from the FCC, because it would cause your phone to claim
an active channel on dozens of towers at once, rather than one or two as is the
The Mythbusters show on the discovery channel tried this Myth out (on the
ground; they weren't allowed to in the air). They built a device that
broadcast broad-band signal on cell frequencies. They couldn't get a certified
aircraft to react at all.
However, they also built a mock-up of a cockpit with just some surplus
instruments. The digital cell phone signal (1.8 GHz or so) didn't produce any
results. However, analog cell signals (900 MHz range) made the VOR go haywire.
SO...I think that depending on shielding, in a homebuilt particularly, an active
analog cell phone on board could very easily cause the VORs to lose their lock. This would be particularly true in a fiberglass airplane, which doesn't have the
natural conductive shielding of a metal airplane.
I've always assumed that the cell phone jack on aviation headsets was to call
flight service to activate or close your flight plan while taxiing, or to call
other people while you're on the ground and the engine is running.