I believe most radio transmissions aboard an aircraft are not allowed. The way it was explained to me is that one cell phone won't effect the pilot's equipment, but if everyone used one the combined signals would interfere. But I wonder why it is that most 2 way transmissions are not allowed, but those air to ground phones which charge prohibitively expensive rates are allowed. Is there really a legitimate concern or is it a money thing? Harvey "There is only one thing worse than waiting upon God, and that is wishing you had." Dr. Charles Stanley.