Final Call for Flight 5G: why are new base stations grounding flights in the US?

US telcos are powering down 5G towers near airports, as airlines suspend flights to major travel hubs. Why is the 5G switch-on now making some aviation experts nervous?

5G has been blamed for everything from COVID to killing birds, but there’s one sector where its rollout is now causing some very real concerns, with significant consequences for global travel.

Several major airlines have suspended routes to certain US destinations over concerns that 5G base stations near airport runways may cause interference with aircraft sensors, following warnings from the Federal Aviation Administration (FAA).

Chief executives of American Airlines, Delta, Southwest Airlines and United Airlines sounded the alarm in November 2021, warning the Biden administration of the “catastrophic” effects of the switch-on.

Verizon and AT&T, the two telcos driving the 5G rollout, planned to launch 5G in December, but delayed until early January, and once again until 19^th January. Now, they’ve agreed with the Department of Transportation to postpone switch-on near key airports for six months, and to implement a buffer zone around runways.

But it was too little too late, as Emirates announced earlier this week that it will suspend flights to several major airports in the US “until further notice.”

Flights will no longer go ahead to Boston, Chicago, Dallas Fort Worth, Houston, Miami, Newark, Orlando, San Francisco and Seattle due to “operational concerns associated with the planned deployment of 5G mobile network services,” though flights will continue to John F. Kennedy International, Dulles International and Los Angeles International (LAX).

Emirates, along with Air India and Japan Airlines, has also cancelled all flights to the US on Boeing 777 planes, the most popular widebody aircraft in the world, while the FAA has issued guidance for Boeing 787 aircraft, warning that 5G interference could prevent aircraft from coming to a stop on the runway.
What about this technology is causing this turbulence?

There is fear that 5G could disrupt readings from onboard radio altimeters, which measure the distance of aircraft from the ground, relaying this data to other safety equipment, including Ground Proximity Warning Systems (GPWS) and collision-avoidance systems.

Unlike standard altimeters that rely on air pressure readings, radio altimeters gauge altitude with radio waves. The 3.7-3.98 GHz frequency of 5G in the US is uncomfortably close to the 4.2-4.4 GHz frequencies of radio altimeters, raising the risk of interference during landing, particularly in older devices. From 2011 to 2020, over half of air traffic accidents occurred during final approach or landing, though the overwhelming majority of these were non-fatal.

Meteorologists have also warned that C-Band frequencies may similarly disrupt hurricane forecasting technology.

Nick Ludlum, SVP and Chief Communications Officer of CTIA disagrees, branding the response as “fearmongering,” arguing that “5G operates safely and without causing harmful interference to aviation operations in nearly 40 countries around the world.”

The EU circumvented this by setting a 3.4-3.8 GHz range for 5G in 2019, well below the range of both radio altimeters and the spectrum that US networks operate on. In addition, France has adopted extensive rules regarding 5G deployments around runways, including larger buffer zones, tilting antennas downward, and lowering their power levels. Similarly, South Korea has its 5G frequencies set at a lower 3.42-3.7 GHz rate.

Japan, though, has theirs as high as 4.1GHz, and has seen no trouble – given that base stations “within 200m from the approaching route of aircraft” are not permitted:

Further study is requested to determine the effect that 5G networks near airports may have on equipment, though both Ofcom and the UK’s Civil Aviation Authority have stated they are “yet to see any evidence that would give us cause for concern.”

Though as we’ve all noted, a lack of evidence hasn’t ever stopped some from believing in the negative effects of 5G!