DNA Explainer: How does 5G technology pose threat to airplanes missing runway?

The super-fast 5G wireless networks is sparking concern among aviation safety experts who fear this could result in interference with the electronics on aircraft, potentially leading to crashes. Air India has curtailed its operations to the United States in view of the deployment of 5G communications there.

Some 50 'high priority' airports in the United States, including the Orlando International Airport will get a temporary buffer zone around it as wireless companies turn on their 5G signals on Wednesday. This comes amid several airlines cancelling flights due to concerns that the new bandwidth would interfere with a critical piece of equipment and lead to crashes in bad weather.

What does 5G have to do with airplanes?

Since 1930s, many airplanes have carried a radio altimeter or a radar altimeter on their underside.

The radio altimeter or a radar altimeter instrument is one more level of safety in the aircraft.

The radar altimeter instrument beams a signal at the ground, which bounces back to the aircraft.

This helps pilot know how far from the ground the plane is and it warns if the plane is approaching land too quickly.

This instrument is particularly useful as it allows a plane to land itself during a rainstorm or fog.

It is also isolated from other systems, meaning it should still work in the event of an equipment failure onboard.

5G's newest bandwidth, known as the C band, operates practically next to the altimeter's range.

The Federal Communications Commission created a small gap between the two and argues it should be enough.

But airline industry executives and Federal Aviation Administration do not agree with FCC's argument.

Aviation regulator warns pilots that interference from 5G towers could make their altimeters inaccurate during landing.

What is the way forward?

As airlines refuse to fly without the support of altimeter, they can fly only on a clear day at the plane's destination.

Aviation experts say some sort of permanent buffer zone was a likely solution, but 20 seconds is too less time for a pilot to ensure safe landing. 

Not all altimeters are affected, so figuring out which aircraft have issues and seeing if they can be modified will be a priority.

There is a lot of concern and so many are asking for 5G rollout to be held back until the testing can be completed.

How will this buffer zone work?

The exclusion zones around certain airports would reduce 5G C-band signal levels by at least 10 times on the runway.

Or it would be reduced during the last mile of final approach and the first mile after takeoff, according to an AT&T.

The carriers agreed to turn off transmitters and make other adjustments near these airports for six months.

This can minimize the potential 5G interference with sensitive aircraft instruments used in low-visibility landings.