Every time we get on a plane, we're asked to either turn off our phones or change them to flight mode—it's for "security reasons". But according to The Conversation website, having to turn our phones off on a plane is "a service issue, not a safety one". When we speak on our phones in the air, they can cause interference to the aircraft's radios and pilots can hear this interference in their headphones. "It's the same noise you'll be familiar with, if you put your mobile too close to a speaker," the Mirror noted. "It is not safety-critical, but is annoying for sure." Though speaking on a phone during a flight isn't dangerous, from the viewpoint of service, it isn't still a good idea.
When we make or receive a call on the ground, we connect to a cell tower that deals with all calls within an 80-kilometer radius (半径).As we move from place to place we are "handed on" to different cell towers. As US scientist Sven Bilen explains, for this system to work, there are "built-in" expectations: There shouldn't be too many "handoffs" and people shouldn't be traveling faster than car speeds. "Of course, phone users should be close to the ground." he added. If we were to make phone calls while we flew, however, none of these expectations would be met. And even worse, our cellphones would stop working.
But now things are beginning to change. If we still can't speak during a flight, we can use other phone functions. For example, Airbus A330 of Emirates Airlines has inflight WiFi to make passengers send and receive short messages in the air. In the future, as Bilen points out, it may be possible for air travelers to make and receive calls freely. The breakthrough could be "pico cells", which are small cell towers on the plane itself. There would no longer be connections made between phones and the ground and therefore there would be no danger of disruption to phone service.
One day, perhaps, we will be chatting in the air as much as we chat on the ground.
