Over the last couple of days, airlines from across Asia, the Middle East and Europe have been cancelling hundreds of flights to the U.S., be it passenger or cargo. No, this not due to a virus, but because there is a new problem in the air. It relates to the launch of 5G services in the U.S. by leading telecom service providers — Verizon and AT&T.

As service providers started switching on telecom towers near airports, so did the airline cancellations. Air India stopped flights to New York, Newark, Chicago and San Francisco. Now, the telcos have agreed to a partial delay in activating their 5G networks near airports to allay airline safety concerns.

So what are the concerns that airlines have over the launch of 5G services?

The aviation industry has all along raised concerns over safety associated with the roll-out of 5G services. The nub of the problem lies in the possible interference with airplanes' radio altimeters, particularly in bad weather.

Altimeters, which measure the distance between a plane and the ground, operate in the 4.2-4.4 GHz range. They are crucial for landing aircraft in low-visibility conditions like heavy fog, snow and rain. This happens to be very close to the 3.7-3.98 GHz range, better known as the 'C band', for which 21 U.S. mobile operators paid over $81 billion in the spectrum auction that ended in February 2021. The big spender was Verizon with $44 billion followed by AT&T at $23 billion.

It is not that all aircraft are impacted. The impact is primarily on the Boeing 777 series. Korean Air, South Korea's biggest airline, switched four passenger planes from Boeing 777s to 787s and 2 cargo planes from 747-8s to 747-400s overnight. Not many airlines have the airplanes or the capacity to switch aircraft at short notice.

So does that mean flights in India will also get cancelled once Indian operators like Airtel and Reliance Jio start the roll-out of 5G services during FY2023? That’s unlikely, because the Telecom Regulatory Authority of India (TRAI) consultation paper clearly specifies: “It has been decided by the government that spectrum in the frequency range 3.3-3.67 GHz should be made available to the telecom service providers for International Mobile Telecommunications (IMT)/5G through auction.”

Since there is a wider buffer of 530 MHz in India between the highest range of the C band (3.67 GHz) and the lowest range of the altimeter band (4.2 GHz), it is unlikely to cause any such issues in India. By ensuring that there is increased frequency spectrum spacing between 5G and radar altimeters, the problem can be resolved. Other countries are using reduced power-level limits to mitigate the problem.

For the beleaguered global airline industry that has just scraped through two years of Covid-19-induced closures, 5G is the newest hurdle in 2022. As things stand, it is going to be restricted to the U.S., the world’s largest aviation market.

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