Dave Holford wrote:

All this while the air travel industry is considering allowing
passengers to use their own cell phones WHILE THE PLANES ARE
IN FLIGHT by adding cell-phone relay stations to the planes

I am familiar with a number of totally RF screened environments
where use of electronic devices are tightly controlled.
However, internal relays are used to permit operation of cell
phones

The point was not how the planes are being equipped to handle
in-flight cell-phone use.

The point was that consideration is being made to allow cell phones to
be used while the planes are in flight. That intentional radiating
PED's are even being considered for in-flight use when so much hype
and concern is being given to the weak radiation potential of some
non-intentional radiators like am/fm radios.

BTW, what is the potential of the local oscillators of small hand-held
LCD-screen TV's to overlap with aviation frequencies?