Wi-Fi takes to the skies

As we all know use of electronic devices in-flight was prohibited but that has changed which means you could use your tablet, e-reader or laptop throughout the entire flight.

The ban over the use of electronic devices in-flight was often been attributed to the possibility of electronic interference with flight equipment in the modern era of fly-by-wire planes, which control flight systems using electronic signals rather than physical movement of connect cables.

Another often cited reason for the ban was the possibility that electronic devices such as Kindles, tablets and laptops could turn into projectiles within the cabin if the plane experiences turbulence – though that should also apply to books and other non-electronic devices too, of course.

Although the ban has been lifted there are still some devices which you still cannot use, like for instance mobile phones with the mobile network radio switched on. A mobile phone searching for a network operator emits higher energy radio waves than one that’s connecting to a device over Bluetooth or to a network via Wi-Fi, and therefore they are considered more likely to cause electromagnetic interference.

So how DOES this wonderful technology work?

Some of the technology behind the miracle of airplane wi-fi largely resembles the gear that delivers wireless internet on the ground. Airplanes use many of the same towers and satellites that deliver data to our smartphones, connecting to towers on the ground, or to satellites, or to both. Air-to-ground (ATG) connectivity is ostensibly faster, since the towers on the ground are closer.

They may be using the same equipment that people on the ground use, but airplanes need to hold onto network signals as they zip through the air at around 886 kilometres per hour.

Because an airplane is moving through the stratosphere at such high speeds, the antenna must constantly maintain a connection to any given tower or satellite. It doesn’t help that the satellites themselves are orbiting the Earth at 28968 kilometres per hour. At a certain point, the antenna will have to find a new tower or satellite. Some antennas do this with motors that pan and tilt to catch a signal. Of course, strapping an antenna onto the top of a plane isn’t great for aerodynamics. The basic workaround for now is to stash it in a little bubble on top of the fuselage called a radome. In the near future, these antennas will be almost invisible from the outside of the plane.

Century Avionics based in Lanseria supplies some of the best in-flight internet equipment in Southern Africa.